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Levothyroxine and aspirin: A case-control study of levothyroxine and the risk of colorectal cancer

Hyperthyroidism, Thyroid Storm, and Graves Disease Treatment & Management: Emergency Department Care, Consultations


Erik D Schraga, MD Staff Physician, Department of Emergency Medicine, Mills-Peninsula Emergency Medical Associates

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Howard A Bessen, MD Professor of Medicine, Department of Emergency Medicine, University of California, Los Angeles, David Geffen School of Medicine; Program Director, Harbor-UCLA Medical Center

Howard A Bessen, MD is a member of the following medical societies: American College of Emergency Physicians

Disclosure: Nothing to disclose.

Chief Editor

Romesh Khardori, MD, PhD, FACP Professor of Endocrinology, Director of Training Program, Division of Endocrinology, Diabetes and Metabolism, Strelitz Diabetes and Endocrine Disorders Institute, Department of Internal Medicine, Eastern Virginia Medical School

Romesh Khardori, MD, PhD, FACP is a member of the following medical societies: American Association of Clinical Endocrinologists, American College of Physicians, American Diabetes Association, Endocrine Society

Disclosure: Nothing to disclose.

Additional Contributors

Robin R Hemphill, MD, MPH Associate Professor, Director, Quality and Safety, Department of Emergency Medicine, Emory University School of Medicine

Robin R Hemphill, MD, MPH is a member of the following medical societies: American College of Emergency Physicians, Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

8 Hypothyroidism Medication Mistakes to Avoid

Hypothyroidism, or underactive thyroid, is a condition where the thyroid gland does not produce or secrete the amount of thyroid hormone the body needs.

The goal of hypothyroidism treatment is to replace the thyroid hormone that you are not able to produce. This helps you feel more energized and back to your normal self, says Antonio Bianco, MD, PhD, a professor of medicine at the University of Chicago in Illinois.

After you’re diagnosed with hypothyroidism, your healthcare provider will likely prescribe a synthetic hormone that helps stabilize your thyroid levels, Dr. Bianco says. But there are some guidelines for taking the medication that you need to know about.

Here’s how to avoid the most common hypothyroidism medication mistakes.

1. Taking Your Thyroid Medication With Meals and Snacks

The synthetic thyroid hormone won’t be absorbed properly unless you take it on an empty stomach and wait 45 to 60 minutes afterward before eating, Bianco says.

The simplest way to accomplish this is to take your thyroid medication first thing in the morning. Bianco says he has patients who set an alarm for 5 a.m., take the medication, and go back to sleep to ensure they’re taking it on an empty stomach. If you choose to take your thyroid medication at night, it’s important that you don’t eat for four hours before taking it.

2. Combining Your Synthetic Thyroid Hormone With Other Medication

Just as there shouldn’t be food in your stomach when you take your hypothyroidism medication, it’s also important to avoid taking any other medication at the same time.

Specifically, antacids, calcium, cholesterol drugs, and iron supplements can each interfere with the way the thyroid hormone is absorbed. So, you should take these particular drugs four hours before or after taking your thyroid medication, according to the U.S. National Library of Medicine. Most other medication can typically be taken 45 minutes to an hour after your hypothyroidism treatment, Bianco says.

RELATED: How Is Hypothyroidism Treated? Medications and Supplements to Consider and Avoid

3. Starting or Stopping Other Medication Without Talking to Your Doctor

Some medication will affect the way your thyroid hormone is absorbed, including birth control pills, estrogen, testosterone, seizure drugs, and some depression medication, according to the American Thyroid Association (ATA). That doesn’t mean you can’t take these other drugs — but if you do, make sure your doctor is aware. It will likely just take some trial and error to find the effective dose of thyroid hormone you’ll need as a result, Bianco says. Likewise, any time you stop taking these drugs or make any changes, your thyroid hormone dose may need to be adjusted, and you should see your healthcare provider then, too.

4. Assuming a Change in Medication Brand Isn’t a Big Deal

Per the ATA, every brand and generic thyroid medication contains the same amount of thyroid replacement hormone. However, many endocrinologists believe that there is a variation in hormone content among the various brands, and that there are additional factors that can interfere with how the hormone is absorbed with each one, notes the ADA. Therefore, when getting a prescription filled at the pharmacy, you should not change from one brand to another, from a brand name to a generic, or from one generic to another without first checking with your doctor.

RELATED: 6 Healthy Food Swaps for Hypothyroidism

5. Taking Too Much Thyroid Hormone and Thinking It’s Harmless

The synthetic thyroid hormone T4 is relatively safe, and you shouldn’t worry if you accidentally take an extra dose, Bianco says. But taking an excessive amount could have side effects — it can make you feel tired, affect your sleep and concentration, lead to bone loss, or cause irregular heartbeats, according to the Cleveland Clinic. If you take combination therapy, which contains both T4 and T3, the medication needs to be taken precisely as prescribed, as taking too much can be dangerous. The ATA notes that potential side effects of taking too much combination therapy include a racing pulse, anxiety, trouble sleeping, and problems with your heart and bones. Contact your healthcare provider immediately if you accidentally take more than prescribed.

6. Inconsistently Taking Your Prescribed Thyroid Medication

For your medication to work properly, you need to take it regularly and consistently. Skipping doses, taking your medication in the morning one day and in the evening the next, or taking it with food some days and on an empty stomach other days can affect how the medication is absorbed. You should take the correct dose of medication at the same time, and in the same way, every day, according to the ATA. Use a pillbox or set an alarm on your phone if you need help remembering to take your pill. If you do miss a dose, take the missed dose as soon as you remember, advises the ATA. But if it’s almost time for your next dose, double up the next day because the life of the medication is long in the body, notes the ATA.

RELATED: 6 Ways to Stay On Top of Your Hypothyroid Medication

7. Overindulging on Certain Foods, Which Can Also Affect How Your Thyroid Meds Work

For the most part, you shouldn’t have problems with most foods if you wait at least 45 minutes after taking your thyroid medication before you eat. But if you don’t wait long enough, “certain foods may impair absorption of the hypothyroid medication more than others,” says Deena Adimoolam, MD, an assistant professor of medicine, endocrinology, diabetes, and bone disease at the Icahn School of Medicine at Mount Sinai in New York City. That includes foods that are high in calcium, such as milk, cheese, yogurt, kale, and spinach.

Eating a lot of soy has also been thought to impair the absorption of thyroid hormone, but a review of studies published in December 2016 in the journal Nutrients noted that it’s not necessary for most people with thyroid disease to avoid soy foods because medication dosage can be adjusted accordingly, if necessary. If you eat about the same amount every day, your healthcare provider has probably found the proper dose of thyroid hormone to counteract soy’s effects. So just be sure to stay consistent with your soy intake.

RELATED: How Diet and Lifestyle Choices Can Help You Manage Hypothyroidism

8. Not Talking to Your Doctor Before Taking Supplements

Your healthcare provider should know about any supplements you take because they may affect your hypothyroidism treatment — particularly iodine. While iodine is essential for your body to produce thyroid hormone, the vast majority of people in the United States get enough iodine from food and water alone, Dr. Adimoolam says. Because taking too much iodine can cause thyroid hormone levels to go too high or too low, it’s best to avoid this supplement.

RELATED: Iodine Defined: Why You Need the Nutrient

Additional reporting by Deb Shapiro.

5 Surprising Things That Affect Your Thyroid Medication

Your thyroid is a small butterfly-shaped organ that sits above your Adam’s apple. This endocrine powerhouse affects your metabolism, your heartbeat and your ability to stay warm, among other things. Unfortunately, thyroid disease is very common – more than 12% of all Americans will be diagnosed with some form of it in their lifetimes. An underactive thyroid (hypothyroidism) is more common than an overactive thyroid (hyperthyroidism): About 5 in 100 Americans have hypothyroidism, while 1 in 100 have hyperthyroidism.

Your Thyroid’s Daily Dose

Hypothyroidism is typically treated with a daily dose of replacement thyroid hormone. While this medication can help manage a sluggish thyroid, there are a number of outside factors that can throw your hormone levels out of whack, even if you’re actively treating them.

“Thyroid hormone medications are very difficult to absorb,” explains Shiri Levy, M.D., an endocrinologist with Henry Ford Health System. “They have to be taken on an empty stomach and a number of factors can interfere with absorption.”

Getting Back in Balance

When the delicate balance of thyroid hormones is upset, your whole body can be affected. You might feel more tired, be more likely to gain weight or navigate your days in a lethargic brain fog. It makes sense then to identify – and eliminate – some of the most common culprits that upset thyroid levels:

  1. Hormones. Whether you’re taking hormone replacement therapy or popping a daily birth control pill, taking other hormones at the same time as your thyroid medication can interfere with its effectiveness. “Hormones like estrogen and progesterone can bind to thyroid hormone and prevent absorption,” explains Levy. An easy solution? Take the two medications an hour apart.
  2. Multivitamins. Like hormones, minerals like iron and calcium can bind to thyroid hormone and inhibit absorption. A good rule of thumb: “Take your thyroid hormone first thing in the morning, on an empty stomach, and take multivitamins and other supplements at lunch, at least 4 hours later,” suggests Levy.
  3. Coffee. The caffeine or coffee itself isn’t a problem, but many people drink coffee with cream or milk. The calcium in dairy products can interfere with thyroid hormone absorption. Wait an hour after taking your thyroid medication to have your cappuccino or latte. Or start taking your coffee black.
  4. Autoimmune inflammation. The primary cause of hypothyroidism is Hashimoto’s disease, a condition where your own immune system attacks the thyroid gland. Doctors aren’t clear what causes Hashimoto’s, but some research suggests a viral or bacterial infection may be one culprit. While there are no current treatments for the autoimmune reactions, working with a knowledgeable physician can ensure you receive a proper diagnose and manage Hashimoto’s disease appropriately.
  5. Prescription medications. Many different types of prescription medications can interfere with replacement thyroid hormones, including drugs that treat breast cancer, depression, osteoporosis and diabetes. Read the fine print on all prescription drugs and ask your doctor or pharmacist if the medications you’re taking can interfere with your thyroid medication.

The key to maintaining healthy thyroid function is establishing a routine that maximizes absorption of your medication. Take your thyroid pill on an empty stomach and wait at least one hour before eating. Still not feeling 100%? Talk to your doctor about issues that mimic a sluggish thyroid, such as vitamin D or vitamin B12 deficiencies.

Want more advice from our health experts?
Subscribe to receive a weekly email of our latest articles, including more on managing thyroid issues.

To find a doctor at Henry Ford, visit henryford.com or call 1-800-HENRYFORD (436-7936).

Dr. Shiri Levy is a board-certified physician who specializes in managing disorders of the thyroid, parathyroid, pituitary, and adrenal glands, lipids, osteoporosis and diabetes. She sees patients at Henry Ford Medical Centers in Novi and Detroit, and is the service chief of endocrinology at Henry Ford West Bloomfield Hospital.

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  • Food and drug interactions – Thyroid UK

    There are various foods, drugs and supplements that can cause problems for the thyroid and for people taking thyroid hormone replacements.  You need to be aware of these food and drug interactions and ensure that you either take them a few hours away from taking your thyroid medication or make sure that, if they decrease your levels, you increase your dosage.  Make sure you have regular thyroid function tests if you start taking any new drugs or supplements and be guided by your clinician.

    Please follow the advice of your clinician or pharmacist and especially before stopping any medication because of suspected food and drug interactions.

    Foods that can cause problems

    Goitrogenic foods

    Goitrogenic foods can act like an antithyroid drug in disabling the thyroid function. They prevent the thyroid from using available iodine. It is made worse if you use a lot of salt because that causes the thyroid to swell. Do not eat these in large amounts if you are taking thyroid hormone replacement. It is thought that the enzymes involved in the formation of goitrogenic materials in plants can be destroyed by cooking, so cook these foods thoroughly if you want to eat them:

    • Brussels sprouts, rutabaga, turnip, cauliflower, cabbage and kale
    • almonds, peanuts and walnuts
    • sweetcorn, sorghum and millet
    • raw swede, turnip and kale


    There is still debate over whether soya interferes with absorption of levothyroxine.  Some studies have shown no effect and some have shown an effect on women.  Therefore, it may be prudent to not eat soya near the taking of your levothyroxine

    “a synthetic thyroid hormone commonly given to treat an under-active thyroid. It is also known as L-thyroxine”

    .  Leaving a gap of four hours should ensure that it doesn’t interfere with your medication.


    Too much dietary fibre can affect the absorption of your levothyroxine so try to eat any fibrous foods away from the time you take your thyroid medication.


    Kelp comes from seaweed and is naturally high in iodine

    “chemical element”

    .  Kelp can therefore interfere with thyroid function.  Although iodine is needed to make thyroxine

    “the main hormone secreted into the bloodstream by the thyroid gland. It is the inactive form”

    and causes problems if you are deficient, those who are not deficient have no need to take it.  If you take more iodine than you need it can cause problems for the thyroid such as overactivity.  It can also have the opposite effect and make you more hypothyroid.


    Coffee can interfere with absorption of levothyroxine so do not take your levothyroxine at the same time as drinking coffee – it’s probably best to wait at least an hour before partaking in your morning cup of coffee

    Supplements that can stop the absorption of levothyroxine


    Some calcium

    “a mineral found in many foods. The body needs calcium to maintain strong bones and to carry out many important functions. Almost all calcium is stored in bones and teeth, where it supports their structure and hardness”

    -rich foods and supplements interfere with levothyroxine absorption. A gap of 4 hours between the two would be adequate to ensure there is no significant impact on blood thyroxine levels. If you are trying to lose weight and use lower fat milk (i.e. semi-skimmed or skimmed), this remains high in calcium despite being lower in fat.


    Iron tablets (ferrous sulphate) can interfere with the absorption of levothyroxine. It’s best to wait two hours before taking your iron tablets. Be aware that some multivitamins may contain calcium and iron.

    Drug interactions

    Medicines that can strain your thyroid

    Any of the following can interfere with the smooth working of the gland, or at least upset the tests:

    • tolbutamide (Rastinon), for diabetes
    • chlorpropamide (Diabinese), also for diabetes
    • phenylbutazone (Butacote) for ankylosing spondylitis
    • diazepam (Valium) for anxiety
    • heparin, to prevent clotting in heart problems. (NB: Blood thinning drugs like warfarin, Coumadin or Heparin can on occasion become stronger in the system when thyroid hormone is added to the mix.)
    • lithium (Priadel) to prevent relapse in psychiatric illness. More than a third of people taking lithium develop an underactive thyroid
    • beta blockers (e.g. Propranolol, Inderal) for high blood pressure
    • salicylates

      “medication such as aspirin”

      , including aspirin (e.g. Disprin), a pain killer

    • steroids (e.g. prednisolone) for any severe physical reaction
    • phenothiazines (e.g. Largactil) major tranquillisers
    • amiloride (e.g. Moduretic) a water tablet
    • androgens

      “any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics”

      (e.g. testosterone) male sex hormone

    • tamoxifen

      “a drug that blocks the actions of oestrogen and is used to treat and prevent some types of breast cancer”

      , an anti-oestrogen

      “the primary female sex hormone. Also known as estrogen ”

      to ward off breast cancer

    • sulphonamides, anti-bacterial drugs
    • acetazolamide (Diamox) for glaucoma and fluid retention
    • resorcinol (Anusol) used for piles
    • PAS for tuberculosis
    • prochlorperazine (Stemetil) for nausea and vomiting

    All of these medicines suppress thyroid activity, so that the level of T4 in the blood is low, even if the gland is perfectly healthy.  Sometimes, particularly with lithium, Hashimoto’s disease develops.

    Drugs that affect the absorption of levothyroxine

    • ciprofloxacin – an antibiotic
    • antacids – most of these contain aluminium hydroxide and is well known for reducing the body’s ability to absorb thyroxine.
    • laxatives
    • colestipol – a cholesterol lowering drug
    • colestyramine – a cholesterol lowering drug
    • sulcralfate – used to treat ulcers and other gastrointestinal problems
    • raloxifene – given for postmenopausal osteoporosis

      “medical condition in which the bones become brittle and fragile from loss of tissue, typically as a result of hormonal changes, or deficiency of calcium or vitamin D”

    • Proton pump inhibitors – given for esophageal reflux disease (GERD) and stomach ulcers to lower stomach acid levels
    • Orlistat (Xenical) – given for weight loss

     The following medicines have a different effect

    • Phenytoin and related medicines – these anticonvulsants, used to control epilepsy, use up the thyroid hormones unusually quickly, and this may cause a shortage
    • Phenobarbital and Carbamazepine – can accelerate the degradation and increase the dose requirement for L-T4
    • Diphenylhydantoin may interfere with thyroxine binding to proteins

      “plant or animal tissue”

      and thereby reduce T4 levels

    • Valproic acid – causes an increase in TSH levels in children (subclinical

      “not detectable, or producing effects that are not detectable, by the usual clinical tests”


      “a term used to describe an under-active thyroid gland”


    • Carbamazepine (Tegretol) – this anticonvulsant inhibits the release of T4 into the blood
    • Co-trimoxazole (Septrin) – for urinary infections – also inhibits the release of T4 into the blood
    • Levodopa (Sinemet) and bromocriptine (Parlodel) are both used for Parkinson’s disease and both stop the stimulating action of TSH, leading to less T4 and T3
    • Adrenaline

      “a hormone secreted by the adrenal glands that increases rates of blood circulation, breathing, and carbohydrate metabolism and prepares muscles for exertion”

      – Anaesthetic

      “a substance that causes lack of feeling or awareness, dulling pain to permit surgery and other painful procedures”

      used by dentists

    Medicines that seem to increase T4 and T3

    Note that neither of these drugs actually stimulates the production of more hormones.

    • Frusemide-type water tablets (e.g. Lasix) by getting rid of fluid, make the blood more concentrated so there is more of the hormones per millilitre
    • Oestrogen (in the contraceptive pill and HRT), provides more of the transport protein making the hormone inactive. Any oestrogen raises the levels although thyroid activity is unchanged.  This could make your levels look within the normal range, whereas they are really below it. After starting on any oestrogen therapy, a woman should always have TSH tested to see if the oestrogen is having an impact on overall TSH and thyroid function and may require a dosage adjustment

    Medicines containing iodine

    Be wary of these if you have ever had a thyroid problem, and think if it could be your thyroid if you get some puzzling symptoms when you are taking one of them.  These medicines are liable to give your thyroid more iodine than it can cope with.  It may react by going into overdrive and producing too much hormone, with anxiety and palpitations

    “a noticeably rapid, strong or irregular heartbeat due to agitation, exertion or illness”

    in consequence, especially to start with.  The usual end result, however, is near-complete downing of tools by the gland so that it runs into obvious underactivity, and general bodily slowing up.

    • Amiodarine (Cordarone X) is an excellent medicine for tricky faults in the rhythm of the heart, but it causes thyroid problems in 6% of people taking it.  These may be due to either under or overactivity, with totally different symptoms: snail-pace or edgy speed.  Since it takes a long time to clear Amiodarone from the circulation, and anyway it may be vital for the heart, it is usually best to continue with it, but help the thyroid with other drugs. These will be thyroxine in the case of underactivity, or an antithyroid such as Carbimazole

      “the most commonly used medicine for hyperthyroidism. It works by reducing the amount of thyroid hormones which your thyroid gland makes”

      in the opposite situation

    • Cough medicines containing iodides including over the counter preparations are not for you if you’ve ever had a thyroid problem
    • X-ray contrast media given, for instance, for gall-bladder investigation.
    • Povidone skin antiseptic (Betadine) and tincture of iodine. Very little iodine is likely to get into the system from these but they should be avoided during pregnancy
    • Multivitamin/multimineral supplements


    Salicylate is a term used to describe a group of drugs that are chemically related to salicylic acid, which is a simple, single-ringed organic molecule that occurs naturally as a component of salicylin (a glucoside found in Willow Bark) and methyl salicylate (in Oil of Wintergreen). These natural products are usually used in the treatment of rheumatism. However, in 1899 the semi synthetic drug Acetylsalicylic acid was introduced under the name Aspirin.

    Salicylates can cause various metabolic changes such as changes in acid-base balance and electrolyte balance, which can, in turn, alter blood pressure and heart rate. However, mechanism of action seems to be as follows in respect of the thyroid hormones.

    Thyroxine hormone binds to certain hormones in the blood called TBG Proteins.  However, thyroxine can be displaced from TBG Proteins by certain substances such as drugs.  In addition, if the amount of TBG Protein changes, this will alter the amount of thyroxine in the blood.

    Some products used to treat acne and skin disorders contain Salicylates, but since these are used topically

    “applied to body surfaces such as the skin”

    as are Oil of Wintergreen (typically found in Relax, Deep Heat etc.) we do not know what effects these have on the thyroid.

    Drugs Containing Salicylates
    • Aspirin  (acetylsalicylic acid)
    • Salicylic acid
    • Methyl Salicylate (Oil of Wintergreen)
    • Sodium Salicylate
    • Diflunisal

    Other Drug and Chemical interactions

    • Prempak C/Premanin etc – HRT made from mares urine that interferes with thyroid availability
    • Amiodarone hydrocholoride – this is an anti-arrythmic and should not be given to patients with thyroid disorders. If you are on this drug you should be regularly tested for thyroid disease
    • Insulin

      “a hormone produced in the pancreas which regulates the amount of glucose in the blood”

      and similar oral

      “relating to the mouth”

      hypoglycaemic drugs – given for diabetes, this can reduce the effectiveness of thyroid hormone.  Be sure your doctor knows you are on one before prescribing the other.  If you are on insulin or an oral hypoglycaemic, you should be closely watched during the initiation of thyroid replacement hormone

    • Cholesterol-Lowering drugs (statins) – these drugs bind thyroid hormones, and a minimum of four to five hours should elapse between taking these drugs and thyroid hormones
    • Oxymetazoline Hydrochloride – a sympathomimetic, an alpha-adrenoreceptor stimulant used in nasal decongestants. This drug works indirectly through the release of Noradrenaline

      “a hormone which is released by the adrenal medulla, increasing blood pressure and heart rate, and by the sympathetic nerves and functions as a neurotransmitter”

      from sympathetic nerve endings. This drug should have a warning on to administer  with caution to patients with heart, kidney

      “a pair of organs in the abdominal cavity that excrete urine”

      and thyroid disorders, diabetes and hypertension

    • Dihydrocodeine Tartrate – an analgesic for the relief of moderate to severe pain. Should only be given in reduced dosages to people with hypothyroidism

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    Date updated: 23/08/21 (V1.4)
    Review date: 09/04/22

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    Levothyroxine 100mcg tablets – Summary of Product Characteristics (SmPC)

    This information is intended for use by health professionals

    Eltroxin 100mcg tablets

    Levothyroxine 100mcg tablets

    Each tablet contains 100 micrograms Levothyroxine sodium anhydrous.

    Excipient with known effect

    Lactose 48.86mg per tablet

    For the full list of excipients, see section 6.1.


    White, uncoated, biconvex tablets engraved on one face with “LT” and “100” on the other.

    Recommended clinical indications: Control of hypothyroidism, congenital hypothyroidism in infants, acquired hypothyroidism in children and juvenile myxoedema.


    In younger patients, and in the absence of heart disease, a serum Levothyroxine (T4) level of 70 to 160 nanomols per litre, or a serum thyrotrophin level of less that 5 milli-units per litre should be targeted. A pre-therapy ECG is valuable because ECG changes due to hypothyroidism may be confused with ECG evidence of cardiac ischaemia. If too rapid an increase in metabolism is produced (causing diarrhoea, nervousness, rapid pulse, insomnia, tremors, and sometimes anginal pain where there is latent cardiac ischaemia,) dosage must be reduced, or withheld, for a day or two, and then re-started at a lower dose level.


    Initially 100 micrograms daily, preferably taken before breakfast or the first meal of the day. Adjust at three to four week intervals by 50 micrograms until normal metabolism is steadily maintained. The final daily dose may be up to 100 to 200 micrograms.


    As for patients aged over 50 years.

    For patients over 50 years, initially, it is not advisable to exceed 50 micrograms daily. In this condition, the daily dose may be increased by 50 micrograms at intervals of every 3-4 weeks, until stable thyroxine levels are attained. The final daily dose may be up to 50 to 200 micrograms.

    Patients over 50 years with cardiac disease

    Where there is cardiac disease, 25 micrograms daily or 50 micrograms on alternate days is more suitable. In this conditions, the daily dose may be increased by 25 micrograms at intervals of every 4 weeks, until stable thyroxine levels are attained. The final daily dose may be up to 50 to 200 micrograms.

    For patients aged over 50 years, with or without cardiac disease, clinical response is probably a more acceptable criteria of dosage rather that serum levels.

    Paediatric population

    The maintenance dose is generally 100 to 150 micrograms per m² body surface area. The dose for children depends on their age, weight and the condition being treated. Regular monitoring using serum TSH levels, as in adults, is required to make sure he/she gets the right dose. Infants should be given the total daily dose at least half an hour before the first meal of the day.

    Congenital hypothyroidism in infants:

    For neonates and infants with congenital hypothyroidism, where rapid replacement is important, the initial recommended dosage is 10 to 15 micrograms per kg BW per day for the first 3 months. Thereafter, the dose should be adjusted individually according to the clinical findings and thyroid hormone and TSH values.

    Acquired hypothyroidism in children:

    For children with acquired hypothyroidism, the initial recommended dosage is 12.5-50 micrograms per day. The dose should be increased gradually every 2 to 4 weeks according to the clinical findings and thyroid hormone and TSH values until the full replacement dose is reached.

    Juvenile myxoedema in children:

    The initial recommended dosage is 25 micrograms daily. In such conditions, the daily dose may be increased by 25 micrograms at intervals of every 2 – 4 weeks, until mild symptoms of hyperthyroidism is seen. The dose will then be reduced slightly.

    In children under 5 years of age, the administration of whole tablets is not recommended. It is also not recommended that tablets are crushed and dispersed in water or other liquids, owing to limited solubility which could lead to dosing inaccuracy. In this age group it is preferable to administer an approved oral solution of levothyroxine.

    Method of administration


    • Hypersensitivity to the active substance or to any of the excipients listed in section 6.1.

    • Thyrotoxicosis

    • Adrenal gland disorder or adrenal insufficiency

    Levothyroxine should be introduced very gradually in patients aged over 50 years (see section 4.2) and those with long standing hypothyroidism to avoid any sudden increase in metabolic demands.

    Patients with panhypopituitarism or other causes predisposing to adrenal insufficiency may react to levothyroxine treatment, and it is advisable to start corticosteroid therapy before giving levothyroxine to such patients.

    Levothyroxine sodium should be used with caution in patients with cardiovascular disorders, including angina, coronary artery disease, hypertension, and in the elderly who have a greater likelihood of occult cardiac disease.

    To minimise the risk of adverse effects of undetected overtreatment, such as atrial fibrillation and fractures associated with low serum levels of thyroid stimulating hormone (TSH) in older patients, it is important to monitor serum TSH and adjust the dose accordingly during long term use.

    In individuals suspected to have cardiovascular disease or to be at high risk, it is important to perform an ECG prior to commencement of levothyroxine treatment in order to detect changes consistent with ischaemia in which case, levothyroxine should be initiated at a low dose, followed by cautious dose escalation to avoid worsening of ischaemia or precipitation of an infarct.

    Special care is needed for the elderly and for patients with symptoms of myocardial insufficiency, or ECG evidence of myocardial infarction.

    Thyroid replacement therapy may cause an increase in dosage requirements of insulin or other anti-diabetic therapy (such as metformin). Care is needed for patients with diabetes mellitus, and diabetes insipidus.

    See note above regarding withdrawal of treatment.

    Subclinical hyperthyroidism may be associated with bone loss. To minimise the risk of osteoporosis, dosage of levothyroxine sodium should be titrated to the lowest possible effective level.

    Parents of children receiving thyroid agent should be advised that partial loss of hair may occur during the first few months of therapy, but this effect is usually transient and subsequent regrowth usually occurs.

    Care is required when levothyroxine is administered to patients with known history of epilepsy. Seizures have been reported rarely in association with the initiation of levothyroxine sodium therapy and may be related to the effect of thyroid hormone on seizure threshold.

    Haemodynamic parameters should be monitored when levothyroxine therapy is initiated in very low birth weight preterm neonates as circulatory collapse may occur due to the immature adrenal function.

    A small number of patients report adverse events on changing between different levothyroxine products. In some cases, symptoms are reported despite thyroid function tests within the reference range. If patients report side effects on switching between products, consider thyroid function testing. For patients who are persistently symptomatic after switching, whether they are biochemically euthyroid or have evidence of abnormal thyroid function, consider consistently prescribing a specific levothyroxine product that is well-tolerated by the patient. If symptoms or poor control of thyroid function persist despite adhering to a specific product, prescription of levothyroxine in an oral solution formulation should be considered.


    Patients with rare hereditary problems of galactose intolerance, total lactase deficiency or glucose-galactose malabsorption should not take this medicine.

    This medicine contains less than 1 mmol sodium (23 mg) per tablet, that is to say essentially ‘sodium-free’.

    Interactions affecting other drugs:

    Levothyroxine increases the effect of anticoagulants (Warfarin) and it may be necessary to reduce the anticoagulation dosage if excessive, hypoprothrombinaemia and bleeding are to be avoided.

    Blood sugar levels are raised and dosage of anti-diabetic agents may require adjustment.

    Tricyclic anti-depressants (e.g. amitriptyline, imipramine, dosulepin) response may be accelerated because levothyroxine increases sensitivity to catecholamines; concomitant use may precipitate cardiac arrhythmias.

    The effects of sympathomimetic agents (e.g. adrenaline or phenylephrine) are also enhanced

    Cardiac glycosides: If levothyroxine therapy is initiated in digitalised patients, the dose of digitalis may require adjustment. Hyperthyroid patients may need their digoxin dosage gradually increased as treatment proceeds because initially patients are relatively sensitive to digoxin.

    NSAIDs: False low plasma concentrations have been observed with concurrent anti-inflammatory treatment such as phenylbutazone or acetylsalicylic acid and levothyroxine therapy.

    Beta Blockers: levothyroxine (thyroxine) accelerates metabolism of propranolol, atenolol and sotalol.

    General anaesthetics: Isolated reports of marked hypertension and tachycardia have been reported with concurrent ketamine administration.

    Interactions affecting Levothyroxine:

    Amiodarone may inhibit the de iodination of thyroxine to tri iodothyronine resulting in a decreased concentration of tri iodothyronine, thereby reducing the effects of thyroid hormones.

    Anti-convulsants, such as carbamazepine and phenytoin, enhance the metabolism of thyroid hormones and may displace them from plasma proteins.

    Initiation or discontinuation of anti-convulsant therapy may alter levothyroxine dosage requirements.

    Effects of Levothyroxine may be decreased by concomitant sertraline.

    Absorption of levothyroxine (thyroxine) possibly reduced by antacids, proton pump inhibitors, calcium salts, cimetidine, oral iron, sucralfate, colestipol, polystyrene sulphonate resin and cholestyramine (administration should be separated by 4-5 hours).

    Metabolism of levothyroxine (thyroxine) accelerated by rifampicin, barbituarates, and primidone. (may increase requirements for levothyroxine (thyroxine) in hypothyroidism)

    Imatinib: plasma concentration of levothyroxine (thyroxine) possibly reduced by imatinib.

    Beta blockers may decrease the peripheral conversion of levothyroxine to triiodothyronine.

    Lipid regulating drugs: Lovastatin has been reported to cause one case each of hypothyroidism and hyperthyroidism in two patients taking levothyroxine.

    Sex Hormones: Oestrogen, oestrogen containing product (including hormone replacement therapy) and oral contraceptives may increase the requirement of thyroid therapy dosage. Conversely, androgens and corticosteroids may decrease serum concentrations of Levothyroxine-binding globulins.

    Anti-obesity drugs such as orlistat may decrease levothyroxine absorption which may result in hypothyroidism (monitor for changes in thyroid function).

    A number of drugs may affect thyroid function tests and this should be borne in mind when monitoring a patient on levothyroxine therapy.

    Post-marketing cases have been reported indicating a potential interaction between ritonavir containing products and levothyroxine. Thyroid- stimulating hormone (TSH) should be monitored in patients treated with levothyroxine at least the first month after starting and /or ending ritonavir treatment.


    The safety of Levothyroxine treatment during pregnancy is not known, but any possible risk of foetal abnormalities should be weighed against the risk to the foetus of untreated hypothyroidism.


    Levothyroxine is excreted in breast milk in low concentrations, and it is contentious whether this can interfere with neonatal screening.


    No data available

    Levothyroxine has no or negligible influence on the ability to drive and use machines

    Side-effects are usually indicative of excessive dosage and usually disappear on reduction of dosage or withdrawal of treatment for a few days.

    Adverse reactions listed below have been observed during clinical studies and/or during marketed use and are based on clinical trial data and classified according to MedDRA System Organ Class. Frequency categories are defined according to the following convention:

    Not known (cannot be estimated from the available data)

    System organ class

    Undesirable effects

    Immune system disorders

    Hypersensitivity reaction

    Endocrine disorders

    Thyrotoxic crisis1

    Psychiatric disorders

    Restlessness, agitation, insomnia

    Nervous system disorders


    Cardiac disorders

    Angina pectoris, arrhythmia, palpitations, tachycardia

    Vascular disorders


    Respiratory, thoracic and mediastinal disorders


    Gastrointestinal disorders

    Diarrhoea, vomiting

    Skin and subcutaneous tissue disorders

    Hyperhidrosis, alopecia, rash, pruritus

    Musculoskeletal and connective tissue disorder

    Arthralgia, muscle spasm, muscular weakness

    Reproductive system and breast disorders

    Menstruation irregular

    General disorders and administration site conditions

    Headache, pyrexia, malaise, oedema


    Weight decreased

    1Some patients may experience a severe reaction to high levels of thyroid hormone. This is called a “thyroid crisis” with any of the following symptoms: Hyperpyrexia, tachycardia, arrhythmia, hypotension, cardiac failure, jaundice, confusion, seizure and coma

    Paediatric population

    Heat intolerance, transient hair loss, benign intracranial hypertension, craniostenosis in infants and premature closure of epiphysis in children.

    Reporting of suspected adverse reactions

    Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme Website : www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.


    In most cases there will be no features. Signs of an overdose may include: fever, chest pain (angina), racing or irregular heartbeat, muscle cramps, headache, restlessness, flushing, sweating, diarrhoea, tremor, insomnia and hyperpyrexia. These signs can take up to 5 days to appear. Atrial fibrillation may develop. Convulsions occurred in one child. There may be increased toxicity in those with pre-existing heart disease.


    Give oral activated charcoal if more than 10mg has been ingested by an adult or more than 5mg by a child, within 1 hour. If more than 10mg has been ingested by an adult or more than 5mg by a child, take blood 6-12 hours after ingestion for measurement of the free thyroxine concentration. The analysis does not need to be done urgently but can wait until the first working day after the incident. Patients with normal free thyroxine concentrations do not require follow up. Those with high concentrations should have outpatient review 3-6 days after ingestion to detect delayed onset hyperthyroidism. Features of clinical hyperthyroidism should be controlled with beta-blockers, e.g. propranolol.

    Pharmacotherapeutic group: Thyroid hormones, ATC Code: H03AA01

    Mechanism of action

    Eltroxin is a tablet containing the hydrated form of Levothyroxine sodium which is used for the treatment of hypothyroidism. The thyroid gland is dependent upon 2 active principles for its main hormone activity these are Levothyroxine (tetraiodothyronine) and Tri-iodothyronine (see Goodman and Gilman, 1985). These closely related iodine containing amino acids are incorporated into the glycoprotein thyroglobulin. The chief action of these hormones is to increase the rate of cell metabolism. Levothyroxine is deiodinated in peripheral tissues to form Tri-iodothyronine which is thought to be the active tissue form of thyroid hormone.

    Pharmacodynamic effects

    Tri-iodothyronine is certainly more rapid acting and has a shorter duration of action than Levothyroxine.

    The chief action of Levothyroxine is to increase the rate of cell metabolism


    Levothyroxine sodium is incompletely and variably absorbed from the gastrointestinal tract.


    It is almost completely bound to plasma proteins and has a half-life in the circulation of about a week in healthy subjects, but longer during pregnancy in patients with myxoedema.


    A large portion of the Levothyroxine leaving the circulation is taken up by the liver. Part of a dose of Levothyroxine is metabolised to triiodothyronine.


    Levothyroxine is excreted in the urine as free drug, deiodinated metabolites and conjugates. Some Levothyroxine is excreted in the faeces. There is limited placental transfer of Levothyroxine.

    No further data of relevance.

    Sodium Citrate BP

    Lactose BP

    Maize starch BP

    Powdered acacia BP

    Magnesium Stearate BP

    24 months for polypropylene containers.

    24 months for blister packs.

    Do not store above 25°C. Store in the original package in order to protect from light and moisture.

    Polypropylene container with tamper-evident low density polyethylene lid, containing 28, 56, 112, 100 or 1000 Eltroxin 100mcg tablets.

    Blister packaging PVC/PVDC film (heat treated foil/heat seal lacquer) containing 28, 56 and 112 Eltroxin 100mcg tablets.

    Not all pack sizes may be marketed.

    No special requirements for disposal.

    Any unused medicinal product or waste material should be disposed of in accordance with local requirements.

    Mercury Pharma Group Ltd

    Capital House, 85 King William Street,

    London EC4N 7BL, UK

    Blood sampling with disposable sterile systems

    Free thyroxine (T4 free)

    Free thyroxine (free T4) is a biologically active part of total thyroxine. Thyroxine is one of the most basic hormones synthesized by the thyroid gland and regulates plastic and energy metabolism in the human body. Thyroxine produces up to 90% of all thyroid hormones. The T4 is the predecessor to the T3.

    During normal functioning of the thyroid gland, the content of free T4 does not depend on the concentration of globulin (TSH).In women, the concentration of thyroxine is lower than in men.

    Free T4 is in the blood in a small volume – 0.02-0.04%. If there is no need for a predecessor, then it is deposited in the follicles of the thyroid gland. Free T4 is used in a number of metabolic processes:

    • stimulates the processes occurring in some parts of the brain;
    • increases the rate of protein synthesis;
    • stimulates heat and gas exchange;
    • changes the strength and heart rate;
    • participates in the growth, differentiation of tissues;
    • affects the contractility and muscle fatigue;
    • participates in the formation of resistance to stress, infections;
    • maintains low blood lipids and cholesterol levels.

    Indications for appointment Free thyroxine (free T4)

    Several doctors can prescribe a free thyroxin test at once: an endocrinologist, a pediatrician, a therapist, a gynecologist and a neonatologist.

    An indication for analysis in endocrinology can be:

    • Graves’ disease
    • thyroiditis;
    • hypothyroidism;
    • hyperthyroidism;
    • endemic goiter;
    • Hashimoto’s thyroiditis;
    • thyroid adenoma;
    • iodine deficiency.

    Pediatrician and therapist refer for analysis in such cases:

    • change in body weight for no apparent reason;
    • dry skin;
    • heart palpitations;
    • protrusion of the eyeballs.

    The gynecologist orders an analysis:

    • pregnant women prone to thyroid diseases;
    • for menstrual irregularities;
    • in the diagnosis of the causes of female infertility.

    The neonatologist will give a referral for T4 if the mother has a diagnosed thyroid disease or the child has congenital hypothyroidism.

    In addition to the problems described above, free thyroxine (free T4) analysis can be prescribed in the presence of the following symptoms:

    • high pressure;
    • 90,013 mood swings;

    • baldness;
    • depressive conditions;
    • changes in body temperature, sweating, chilliness;
    • problems with potency, decreased sex drive;
    • memory impairment;
    • stool problems.

    Reference values ​​(laboratory standards)

    The time of day, gender, age, and the presence of pregnancy in a woman can affect the level of T4 in the blood.

    The level of free thyroxine in the blood is measured in picomoles per liter (pmol / l or pmol / l).

    Norms Thyroxine free (T4 free):


    0-12 months: 11-20 pm / ml;

    1-6 years old: 9-17 pm / ml;

    7-12 years old: 11-17 pm / ml;

    13-17 years old: 11-18 pm / ml.


    8.9-17.2 pm / ml.

    Increase in indicator Free thyroxine (T4 free)

    Reasons for an increase in the level of T4 free:

    – Diffuse toxic goiter.

    – Thyroiditis.

    – Thyroid adenoma.

    – TSH-independent thyrotoxicosis.

    – Obesity.

    – Postpartum thyroid dysfunction.

    – Kidney disease.

    – Chronic liver pathology (hepatitis, cirrhosis, etc.).

    – Heparin therapy.

    The thyroxine level can be increased with the following drugs: amiodarone, levothyroxine, propranolol, aspirin, furosemide, valproic acid.Taking anabolic steroids, phenytoin, carbamazepine, clofibrate, methadone, octreotide can reduce thyroxine levels.

    Decrease in indicator Free thyroxine (free T4)

    Reasons for lowering the level of T4 free:

    – Primary hypothyroidism.

    – Endemic goiter.

    – Autoimmune thyroiditis.

    – Thyroid resection.

    – Secondary hypothyroidism.

    – Thyrotropinoma.

    – Inflammatory processes in the pituitary gland and hypothalamus.

    – Lack of iodine.

    – Protein deficiency (depletion).

    – Lead poisoning.

    – Heroin addiction.

    – Taking oral contraceptives.

    Thyroxine levels can be lowered with the following drugs: amiodarone, anabolic steroids, anticonvulsants, clofibrate, isotretionine, methimazole, phenobarbital, phenylbutazone, phenytoin, ranitidine.mestranol, octreotide.

    Sometimes a low T4 level is observed in the absence of clinical manifestations. In this case, you need to consult a doctor for advice.

    90,000 Section 1. Medicines / ConsultantPlus

    Section 1. Medicines

    Anesthesia and hypnotics

    932111 Halothane (Fluorothane)

    932141 Droperidol

    932128 Ketamine hydrochloride

    932127 Sodium oxybutyrate

    932821 Nitrazepam

    931232 Sodium thiopental

    931221 Phenobarbital

    932115 Ether for anesthesia

    931231 Hexobarbital

    932116 Dinitrogen oxide

    932138 Midazolam

    (codes 931231, 932116, 932138 were introduced by Government Decree

    RF from 20.05.99 N 546)


    932136 Bromcamphor

    936131 Valocordin

    936131 Corvalol

    931844 Magnesium sulfate

    Antipsychotics and tranquilizers

    932822 Alprazolam

    932141 Haloperidol

    932822 Diazepam (Sibazon)

    932196 Dicarbine (Carbidine)

    932146 Carbamazepine

    932829 Lithium oxybutyrate

    932828 Medazepam (Mezapam)

    935226 Homopantothenic acid (Pantogam)

    935226 Picamilon

    932198 Piracetam

    932147 Pyritinol (Pyriditol)

    932133 Trifluoperazine (Triftazin)

    937115 Soothing collection

    932138 Phenazepam

    932823 Chloridiazepoxide (Chlosepide)

    932131 Chlorpromazine hydrochloride (Aminazine)

    932824 Oxazepam (Nosepam)

    932149 Levomepromazine

    932133 Pericyazine

    932133 Perphenazine

    932133 Thioproperazine

    932141 Trifluperidol

    932133 Pipothiazine

    932192 Sulpiride

    932133 Thioridazine

    932147 Fluspirylene

    932133 Fluphenazine

    932149 Lorazepam

    932825 Chlorprothixene

    932149 Zuclopentixol

    932197 Moclobemide

    (codes 932149, 932133, 932133, 932133, 932141, 932133, 932192,

    932133, 932147, 932133, 932149, 932825, 932149, 932197 introduced

    Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Narcotic analgesics and narcotic


    936713 Codeine

    936714 Codtermopsis

    936714 Codterpin

    936712 Morphine hydrochloride

    936717 Omnopon

    932158 Prosidol

    932155 Trimeperidine hydrochloride (Promedol)

    932158 Fentanyl

    932159 Pentazocine

    932158 Pyritramide

    932586 Naloxone

    (codes 932159, 932158, 932586 introduced by Government Decree

    RF from 20.05.99 N 546)

    Analgesic, antipyretic, anti-inflammatory

    agents (derivatives of pyrazolone and other chemical groups)

    931314 Askofen P

    931314 Acetylsalicylic acid (Aspirin)

    935881 Vipraxin

    932843 Diclofenac sodium (Ortofen)

    932841 Ibuprofen

    932842 Indomethacin

    931333 Metamizole sodium (Analgin)

    932847 Naproxen

    931341 Paracetamol

    931332 Pentalgin

    932842 Piroxicam

    931315 Salicylamide

    931336 Phenylbutazone (Butadion)

    931314 Citramon P, Citrapa

    932586 Tramadol

    932841 Ketoprofen

    933762 Ketorolac

    (codes 932586, 932841, 933762 were introduced by Government Decree

    RF from 20.05.99 N 546)

    Anticonvulsants and substances,

    used for the treatment of parkinsonism

    933767 Amantadine hydrochloride (Midantan)

    932163 Beclamide (Chloracon)

    932165 Benzobarbital (Benzonal)

    932123 Gluferal

    932149 Sodium valproate (Acediprol)

    932162 Primidone (Hexamedin)

    932146 Trihexyphenidyl hydrochloride (Cyclodol)

    932161 Phenytoin (Diphenin)

    932146 Biperiden

    932149 Valproic acid

    932149 Clonazepam

    932146 Levodopa + Benserazide

    932146 Levodopa + Carbidopa

    932167 Lamotrigine

    932149 Ethosuximide

    (codes 932146, 932149, 932149, 932146, 932146, 932167, 932149

    were introduced by the Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Psychostimulants and antidepressants

    932191 Amitriptyline

    932265 Clozapine (Azaleptin)

    931411 Caffeine

    931413 Caffeine sodium benzoate

    932189 Mesocarb (Sydnocarb)

    932181 Pirindol hydrochloride (Pyrazidol)

    932192 Tiaprid

    932191 Mianserin

    932184 Imipramine

    932183 Clomipramine

    932181 Maprotiline

    932188 Sertraline

    932188 Tianeptine

    932188 Fluoxetine

    932194 Lithium carbonate

    932188 Tianeptine

    932189 Citalopram

    (codes 932191, 932184, 932183, 932181, 932188, 932188, 932188,

    932194, 932188, 932189 introduced by the Decree of the Government of the Russian Federation of

    20.05.99 N 546)


    932175 Nitsetamide (Cordiamine)

    936164 Sulfocamfocaine

    931647 Sulfocamphoric acid

    Acetylcholine, cholinomimetic and

    anticholinesterase agents

    932221 Aminostigmine

    936721 Atropine sulfate

    936287 Bellataminal

    932221 Neostigmine (Neostigmine)

    936738 Pilocarpine hydrochloride

    936724 Platyphylline hydrotartrate

    932228 Dystigmine bromide

    932221 Pyridostigmine bromide

    932269 Timolol

    932263 Dorzolamide

    933762 Latanoprost

    932269 Proxodolol

    (codes 932228, 932221, 932269, 932263, 933762, 932269 introduced by

    Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Adrenaline and adrenomimetics

    932263 Naphazoline (Naphtizin)

    935823 Norepinephrine hydrotartrate

    932262 Salbutamol

    935821 Epinephrine (Epinephrine hydrochloride)

    936771 Ephedrine hydrochloride

    935822 Epinephrine (Epinephrine hydrotartrate)

    932613 Beclomethasone

    932233 Ipratropium bromide + fenoterol

    932233 Ipratropium bromide

    932286 Cromoglycate disodium

    932285 Undercromil

    932263 Terbutaline

    932619 Budesonide

    932262 Saltos

    932263 Phenylephrine

    (codes 932613, 932233, 932233, 932286, 932285, 932263, 932619,

    932262, 932263 were introduced by the Decree of the Government of the Russian Federation of 20.05.99

    N 546)

    Curariform drugs and antiadrenergic drugs

    932191 Propoxane (Pirroxan)

    932272 Suxamethonium chloride (Ditilin) ​​

    932277 Pipecuronium bromide

    932277 Vecuronium bromide

    932275 Atracurium besilat

    (codes 932277, 932277, 932275 were introduced by Government Decree

    RF dated 20.05.99 N 546)

    Local anesthetics

    932311 Benzocaine (Anestezin)

    932319 Lidocaine hydrochloride

    932312 Procaine (Novocaine)

    932313 Tetracaine (Dikain)

    932314 Trimecaine

    932319 Bupivacaine

    932319 Articaine

    932315 Anilocaine

    932332 Acetylcysteine ​​

    932336 Bromhexine

    (codes 932319, 932319, 932315, 932332, 932336 introduced by

    Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Coating, absorbent, binding agents

    932321 Vikair

    932321 Vikalin

    932321 Basic bismuth nitrate

    932451 Nicometamide (Nikodin)

    932284 Ranitidine hydrochloride

    931888 Remagel

    931888 Sukralfat (Venter)

    931891 Activated carbon

    932284 Famotidine

    931891 Enterosorbent

    932238 Pirenzepine

    933763 Omeprazole

    932292 Dalargin

    (codes 932238, 933763, 932292 introduced by Government Decree

    RF from 20.05.99 N 546)

    Products containing essential oils, irritating

    nerve endings of the skin, muscles and mucous membranes,

    bitterness and preparations containing ammonia

    936279 Validol


    932344 Bisacodyl

    936236 Senna, senna extract

    937343 Senna leaves

    Cardiac glycosides of adonis, foxglove, strophanthus

    936312 Digoxin

    936821 Korglikon

    936815 Lanatoside C (Celanide)

    936823 Strofantin K

    Antiarrhythmic drugs

    932423 Asparkam

    932482 Moracizin (Etmozin)

    932426 Procainamide (Novocainamide)

    932269 Propranolol (Anaprilin) ​​

    932424 Etatsizin

    932269 Metoprolol

    932424 Propafenone

    932269 Sotalol

    936763 Quinidine

    (codes 932269, 932424, 932269, 936763 were introduced by Decree

    of the Government of the Russian Federation of 20.05.99 N 546)

    Antispasmodic and antihypertensive drugs

    936773 Aimalicin (Raunatin)

    932269 Atenolol

    932415 Bendazol (Dibazol)

    932487 Verapamil

    932411 Drotaverine hydrochloride (No-shpa)

    932424 Isosorbit dinitrate (Nitrosorbide)

    932589 Inosine (Riboxin)

    932485 Clonidine (Clonidine)

    932413 Xanthinol nicotinate

    932269 Nicergoline

    932425 Nitroglycerin (Nitrogranulong, Trinitrolong,

    Perlinganite, Sustak – forte)

    932411 Papaverine hydrochloride

    932415 Papazol

    932413 Pentoxifylline

    931432 Teofedrin P

    931431 Theophylline (Teopek)

    936772 Triresid

    931433 Theophyllamine (Euphyllin)

    932416 Vinpocetine

    932596 Instenon

    932417 Nimodipine

    931432 Teofedrin N

    932245 Azametonium bromide

    932487 Amlodipine

    932269 Betaxolol

    932269 Doxazosin

    932427 Methyldopa

    932417 Nifedipine

    932427 Fosinopril

    932427 Captopril

    932427 Enalapril

    932427 Quinapril

    932489 Dobutamine

    932489 Dopamine

    (codes 932416, 932596, 932417, 931432, 932245, 932487, 932269,

    932269, 932427, 932417, 932427, 932427, 932427, 932427, 932489,

    932489 were introduced by the Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Diuretics and dehydration agents

    932441 Bumetanide (Bufenox)

    932518 Mannitol (Mannitol)

    937434 Urological collection

    932446 Furosemide

    932448 Chlorthalidone (Oxodolin)

    932445 Indapamide

    932430 Hydrochlorothiazide

    932445 Spironolactone

    (codes 932445, 932430, 932445 were introduced by Government Decree

    RF from 20.05.99 N 546)

    Agents promoting the excretion of uric acid

    and removal of urinary calculi

    932851 Allopurinol

    932556 Ornithine

    936993 Artichoke leaves extract

    932517 Lactulose

    936561 Colchicine

    (codes 932556, 936993, 932517, 936561 introduced by Decree

    Government of the Russian Federation of 20.05.99 N 546)

    Choleretic agents

    936361 Allochol

    Drugs affecting the muscles of the uterus

    935816 Oxytocin

    936752 Ergometrine maleate

    936757 Methyl ergometrine

    935816 Pituitrin

    932355 Dinoprost

    932355 Dinoprostone

    (codes 936757, 935816, 932355, 932355 were introduced by Decree

    of the Government of the Russian Federation of 20.05.99 N 546)

    Vitamins and their analogues

    935413 Askorutin

    935211 Ascorbic acid (Vitamin C)

    935545 Gendevit

    935547 Glutamevit

    932597 Carnitine chloride

    935223 Codecarboxylase (Pyridoxal Phosphate)

    935931 Cocarboxylase

    935547 Complivit

    935273 Lipoic acid

    935271 Menadion (Vicasol)

    935275 Methylmethionine sulfonium chloride (Vitamin U)

    935231 Nicotinic acid (Vitamin PP)

    935412 Oksidevit

    935223 Pyridoxine hydrochloride (Vitamin B6)

    935541 Revit

    935311 Retinol (Retinol acetate and palmitate)

    935222 Riboflavin (Vitamin B2)

    935221 Thiamine chloride (bromide) (Vitamin B1)

    935342 Tocopherol acetate

    935545 Undevit

    935225 Folic acid

    935224 Cyanocobalamin

    935412 Ergocalciferol (Vitamin D2)

    935412 Alfacalcidol

    935412 Calcium carbonate + ergocalciferol

    932341 Cholecalciferol

    935225 Folic acid

    935224 Hydroxycobolamine

    (codes 935412, 935412, 932341, 935225, 935224 are introduced by

    Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Drugs affecting blood clotting

    935864 Heparin

    932587 Calcium dobesylate

    935827 Protamine sulfate

    939377 Statin

    938173 Fibrinolysin

    932422 Emoxipin

    932587 Etamsilat

    932588 Cyclosporin

    935924 Alteplaza

    932530 Allprostadil

    932573 Feracryl

    935864 Calcium nadroparin

    935864 Sodium Enoxaparin

    931314 Ticlopidine

    935924 Streptokinase

    935924 Streptodecase

    932530 Fenindion

    935898 Coagulation factor VIII

    935898 Clotting factor IX

    932573 Iron sucrose

    932573 Iron sulfate

    (codes 932588, 935924, 932530, 932573, 935864, 935864, 931314,

    935924, 935924, 932530, 935898, 935898, 932573, 932573 introduced

    Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Preparations of the pituitary gland, adrenal cortex and their analogs

    932641 Acetomepregenol

    932631 Hexestrol (Sinestrol)

    932618 Hydrocortisone acetate

    932643 Hydroxyprogesterone (Oxyprogesterone capronate)

    935813 Chorionic gonadotropin

    935813 Menopausal gonadotropin

    932614 Deoxycortone

    (Deoxycorticosterone acetate)

    932617 Dexamethasone

    932662 Methandienone (Methandrostenolone)

    932661 Methandriol (Methylandrostenediol)

    932653 Methyltestosterone

    932613 Prednisolone

    932613 Prednisolone hemisuccinate

    932641 Progesterone capronate

    932616 Triamcinolone

    932692 Fluocinolone acetonide (Sinaflan)

    932641 Egestrenol

    932623 Ethinylestradiol

    935835 Calcitonin

    932641 Dydrogesterone

    932643 Norethisterone

    932622 Estradiol

    935833 Estron

    932613 Betamethasone

    935811 Desmopressin

    932626 Clomiphene

    932613 Methyl prednisolone

    935819 Octreotide

    935819 Somatropin

    932611 Tetracosactide

    932618 Fludrocortisone

    935412 Dihydrotachysterol

    932613 Betamethasone + salicylic acid

    936759 Bromocriptine

    932693 Cyproterone

    935813 Menotropins

    932663 Nandrolone

    (codes 935835, 932641, 932643, 932622, 935833, 932613, 935811,

    932626, 932613, 935819, 935819, 932611, 932618, 935412, 932613,

    936759, 932693, 935813, 932663 introduced by Resolution

    of the Government of the Russian Federation of 20.05.99 N 546)

    Insulin preparations and other antidiabetic agents

    932548 Buformin (Glibutide)

    932541 Glibenclamide (Glyformin)

    935841 Highly purified insulin

    932541 Glibenclamide

    932543 Gliclazide

    932541 Glickvidon

    932541 Acarbose

    932543 Glipizid

    935841 Glucagon

    935841 Insulin BD

    935841 Insulin DL

    935841 Insulin KD

    935841 Insulin – Comb

    935841 Insulin SrD

    932549 Metformin

    932541 Glimepiride

    (codes 932541, 932543, 932541, 932541, 932543, 935841, 935841,

    935841, 935841, 935841, 935841, 932549, 932541 introduced

    Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Enzyme preparations and agents with antienzyme activity

    935826 Abomin

    932583 Aminocaproic acid

    935852 Lidaza

    935854 Pancreatin

    935927 Prosubtillin (Profesim)

    935861 Cetochrome-C

    935859 Aprotinin

    935894 Gastric juice

    (codes 935859, 935894 were introduced by the Decree of the Government of the Russian Federation of

    20.05.99 N 546)

    Histamine and antihistamines

    932289 Dimebon

    932281 Diphenhydramine (Diphenhydramine)

    932283 Quifenadine (Fenkarol)

    932284 Mebhydrolin (Diazolin)

    932282 Promethazine (Diprazine)

    932281 Astemizole

    932285 Ketotifen

    (codes 932281, 932285 were introduced by the Decree of the Government of the Russian Federation of

    20.05.99 N 546)

    Plasma substitutes

    938171 Placental albumin

    930000 Gemovekt

    936554 Gemodez, Gemodez H

    936553 Glugyr (blood preservative)

    932512 Glucose

    931858 Disol

    931858 Quintasol

    931858 Lactasol

    931858 Sodium chloride

    931878 Potassium chloride

    931858 Isotonic sodium chloride

    932517 Polyamine solution

    936554 Polyvidone (Enterodez)

    936554 Polyvinylpyrrolidone

    936559 Polyglyukin

    936559 Reogluman

    936559 Reopoliklyukin,

    Rheopolyglucin with glucose

    931858 Ringer-Locke’s solution

    930000 Transvekt

    932559 Trometamol (Trisamine)

    936553 Citrolucophosphate (blood preservative)

    931858 Chlosalt

    931858 Trisol

    931851 Sodium bicarbonate

    932530 Sodium citrate

    (codes 931858, 931858, 931851, 932530 introduced by Decree

    of the Government of the Russian Federation of 20.05.99 N 546)

    Amino acids and sugars

    932596 Gamma – aminobutyric acid (Aminalon)

    932517 Sorbitol (sorbitol)

    931693 Sorbose

    935719 Cerebrolysate

    932517 Amino acids for parenteral nutrition

    936559 Penta starch

    932559 Trometamol

    935898 Infusamine

    935724 Aminocrovin

    936559 Rheopolyglucin with glucose

    935725 Lophenolac

    935713 Phenyl – fries

    935725 Tetrafen

    935713 Afenilak

    935713 Keto analogs of amino acids

    (codes 932517, 936559, 932559, 935898, 935724, 936559, 935725,

    935713, 935725, 935713, 935713 introduced by Resolution

    of the Government of the Russian Federation of 20.05.99 N 546)

    Preparations of calcium, potassium

    932589 Potassium orotate

    931835 Calcium chloride

    Preparations containing phosphorus, arsenic and cobalt,

    antidotes and complexones

    935867 Adenosine triphosphoric acid (ATP)

    932557 Dietixime

    931855 Sodium thiosulfate

    932594 Taren

    932584 Trimedoxin bromide (Dipiroxime)

    932554 Unitiol

    Preparations containing iodine and iodine substitutes

    939215 Glutaral-H

    931811 Iodine

    931812 Yodopiron

    931812 Potassium iodide

    931812 Suliodopiron

    939249 Chlorhexidine bigluconate

    931811 Iodinol

    936554 Polyvidone

    935831 Levothyroxine sodium

    932545 Liothyronine + levothyroxine + potassium iodide + sodium

    propyl benzoate

    932545 Levothyroxine + Liothyronine

    932545 Tiamazole

    932545 Levothyroxine + potassium iodide

    (codes 931811, 936554, 935831, 932545, 932545, 932545, 932545

    were introduced by the Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Drugs affecting the processes of tissue metabolism

    (hyocholosterolemic, anorexigenic, containing bee venoms

    and snakes, photosensitizers and treatments


    932573 Aktiferrin

    932585 Disulfiram (Teturam)

    935717 Taurine (Taufon)

    932416 Cinnarizine

    932500 Erythropoietin

    932269 Tamsulosin

    935889 Prostatilen

    932269 Alfuzosin

    936989 Creeping palm extract

    932844 Lodoxamide

    935717 Cysteine ​​hydrochloride + nicotinic acid +

    glutathione + thiamine + calcium chloride + magnesium

    chloride + potassium iodide

    935861 Cytochrome + sodium succinate + adenosine +

    nicotinamide + benzalkonium chloride

    932597 Pirenoxine

    932597 Azapentacin

    932581 Betamecyl

    935895 Kerakol

    935889 T-activin

    932588 Imunofan

    935889 Timogen

    935889 Vilosen

    932588 Pyrogenal

    936543 Lipostabil

    935870 Plazmol

    932558 Penicillamine

    935865 Chondroitin sodium sulfate

    932588 Glatiramer acetate

    (codes 932269, 935889, 932269, 936989, 932844, 935717, 935861,

    932597, 932597, 932581, 935895, 935889, 932588, 935889, 935889,

    932588, 936543, 935870, 932558, 935865, 932588 introduced

    Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Antiviral agents

    936451 Alpizarin

    933772 Remantadine

    933770 Ridostin

    933771 Florenal

    936991 Helepin

    933777 Zidovudine

    933777 Lamivudine

    933774 Acyclovir

    933774 Ganciclovir

    933777 Stavudine

    933777 Didanosine

    933777 Indinavir

    (codes 933777, 933777, 933774, 933774, 933777, 933777, 933777

    were introduced by the Decree of the Government of the Russian Federation of 20.05.99 N 546)


    934343 Amikacin

    934243 Ampiox sodium

    934243 Ampicillin (Ampicillin trihydrate and sodium


    934211 Benzylpenicillin (Benzylpenicillin potassium and

    sodium salt)

    934213 Benzylpenicillin benzathine (Bicillin-1)

    934215 Benzylpenicillin benzathine (Bicillin-5)

    934346 Gentamicin sulfate

    934452 Doxycycline

    934344 Kanamycin sulfate

    934345 Kanamycin monosulfate

    934245 Carbenicillin

    931732 6-aminopenicillic acid

    934831 Levomekol

    934868 Lincomycin hydrochloride

    934451 Metacyclin

    934511 Nystatin

    934811 Oleandomycin

    934422 Oletetrin

    934242 Oxacillin sodium salt

    934211 Penicillin – procaine (Benzylpenicillin

    novocaine salt)

    934311 Streptomycin sulfate

    934243 Sulacillin

    934243 Sulbactam sodium salt

    934421 Tetracycline (Tetracycline base and hydrochloride)

    934251 Phenoxymethylpenicillin

    934831 Chloramphenicol (Levomycetin, Levomycetin


    934863 Ciprofloxacin

    934621 Cephalexin

    934613 Cefazolin

    934615 Cefotaxime

    934613 Cephalotin

    934813 Erythromycin

    931732 Erythromycin thiocyanate

    934311 Vancomycin

    934867 Meropenem

    934242 Oxacillin

    934621 Cefaclor

    934612 Ceftazidime

    934617 Ceftriaxone

    934614 Cefuroxime

    934343 Amikacin

    934867 Imipenem

    934813 Azithromycin

    934821 Polymyxin B

    934612 Cefoperazone

    934811 Spiromycin

    934534 Amphoglucamine

    934532 Amphotericin B

    934511 Nystatin

    (codes 934311, 934867, 934242, 934621, 934612, 934617, 934614,

    934343, 934867, 934813, 934821, 934612, 934811, 934534, 934532,

    934511 introduced by the Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Sulfanilamide preparations

    931515 Sulfaguanidine (Sulgin)

    931532 Sulfadimethoxine

    931537 Sulfalene

    931531 Sulfamethoxy – pyridazine (Sulfapyridazine


    931534 Sulfamonomethoxin

    931511 Sulfanilamide (Streptocide)

    931534 Sulfaton

    931513 Sulfacetamide (sodium sulfacyl)

    931525 Sulfaetidol (Etazol)

    931527 Phthalylsulfapyridazine (Phtazine)

    931521 Phthalylsulfathiazole (Phthalazole)

    931591 Co – trimoxazole

    931315 Mesalazine

    931513 Sulfacetamide

    (codes 931591, 931315, 931513 introduced by Government Decree

    RF from 20.05.99 N 546)

    Nitrofuran derivatives and various chemotherapeutic agents

    933182 Dioxidine

    933117 Nitroxoline

    933112 Nitrofurantoin (Furadonin)

    933114 Furazolidone

    934863 Norfloxacin

    (code 934863 was introduced by the Decree of the Government of the Russian Federation of 20.05.99

    N 546)

    Anti-tuberculosis drugs

    933811 Isoniazid

    933814 Metazide

    933871 Rifampicin

    933812 Ftivazid

    933835 Mikobutin

    933836 Pyrazinamide

    933836 Prothionamide

    933837 Ethambutol

    933836 Ethionamide

    (codes 933835, 933836, 933836, 933837, 933836 are introduced by

    Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Drugs for the treatment of malaria

    933214 Pyrimethamine (Chloridine)

    933213 Hydroxychloroquine

    933213 Chloroquine

    (codes 933213, 933213 were introduced by the Decree of the Government of the Russian Federation of

    20.05.99 N 546)

    Preparations for the treatment of trichomoniasis, leishmaniasis, amebiasis

    933223 Metronidazole

    933761 Pipemidic acid (Pimidel)

    Preparations for the treatment of fungal diseases, protective pastes

    and dyes

    933430 Bifonazole

    933661 Brilliant green alcohol solution

    934521 Griseofulvin

    933438 Clotrimazole

    933438 Fluconazole

    933434 Terbinafine

    933438 Itraconazole

    933438 Bifonazole

    (codes 933438, 933434, 933438, 933438 introduced by Decree

    of the Government of the Russian Federation of 20.05.99 N 546)

    Antihelminthic drugs (anthelmintic)

    933330 Azinox

    933338 Carbendazim (Medamin)

    933335 Niclosamide (Fenasal)

    933311 Piperazine adipate

    933332 Praziquantel (Biltricide)

    Antiseptic preparations of acids and alkalis

    932382 Dimethyl sulfoxide (Dimexide)

    933631 Methenamine (Hexamethylenetetramine, Urotropine)

    933665 Ethacridine lactate (Rivanol)

    931875 Potassium hypermanganate

    933620 Hydrogen peroxide

    (codes 931875, 933620 were introduced by the Decree of the Government of the Russian Federation of

    20.05.99 N 546)

    Drugs used for the treatment of malignant


    933541 6-Mercaptopurine

    934857 Bleomycin (Bleomycetin)

    934854 Dactinomycin

    934853 Daunorubicin (Rubomycin hydrochloride)

    934856 Doxorubicin

    935225 Calcium folinate

    935928 Rednitine (L-asparaginase)

    935225 Methotrexate

    933513 Sarcolysin

    933542 Fluorouracil (Fluorouracil)

    933551 Phospestrol

    933516 Chlorambucil (Chlorbutin)

    933515 Cyclophosphamide (Cyclophosphamide)

    933586 Cisplatin

    933544 Azathioprine

    933583 Aminoglutethimide

    933531 Busulfan

    936565 Etoposide

    936566 Vinblastine

    936792 Vincristine

    933584 Hydroxycarbamide

    933583 Dakarbazine

    936566 Docetaxel

    933513 Ifosfamide

    934856 Idarubicin

    933584 Gemzar

    933581 Carboplatin

    933513 Melphalan

    934858 Mitomycin

    933581 Procarbazine

    933587 Aranose

    933589 Mitoxantrone

    932591 Bonefos

    933588 Flutamide

    936566 Paclitaxel

    933541 Thioguanine

    933521 Tiotepa

    933545 Cytarabine

    933582 Tretinoin

    933584 Fludarabine

    936566 Irinotecan

    936566 Vinorelbin

    933581 Prospidium chloride

    932641 Medroxyprogesterone

    933582 Tamoxifen

    933554 Goserelin

    933589 Anastrozole

    932525 Lenograstim

    932525 Molgramostim

    932525 Filgrastim

    932338 Ondansetron

    (codes 933544, 933583, 933531, 936565, 936566, 936792, 933584,

    933583, 936566, 933513, 934856, 933584, 933581, 933513, 934858,

    933581, 933587, 933589, 932591, 933588, 936566, 933541, 933521,

    933545, 933582, 933584, 936566, 936566, 933581, 932641, 933582,

    933554, 933589, 932525, 932525, 932525, 932338 introduced

    Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Diagnostic tools

    932711 Adipiodon (Bilignost)

    931846 Barium sulfate

    932714 Iodolipol

    932733 Yofendilat (Etiotrast)

    932719 Sodium amidotrizoate (Triombrast)

    932732 Sodium iopodate (Bilimin)

    932718 Propoidon

    931846 Barium sulfate + sodium citrate + sorbitol +

    antifomsilan + nipagin

    932799 Galactose

    932797 Gadopentenic acid

    932797 Gadodiamide

    932712 Yogeksol

    932733 Iopromide

    932797 Sodium fluorescein

    (codes 931846, 932799, 932797, 932797, 932712, 932733, 932797

    were introduced by the Decree of the Government of the Russian Federation of 20.05.99 N 546)

    Medicinal plant raw materials and products

    937643 Arfazetin (diabetic collection)

    937111 Rhizome with Valerian officinalis roots

    937322 Collection chest N 2

    937432 Bearberry leaf

    937434 Flushes (young shoots) of kidney tea

    937543 Marigold flowers (calendula)

    937317 Chamomile flowers for outdoor use

    and internal use

    Immunobiological preparations

    938570 Nutrient agars and broths for


    938740 Household and epidermal allergens

    938710 Infectious allergens for diagnostics

    and treatment (except for diagnostic tests for PPN test)

    938720 Infectious diagnostic allergens

    for test PPN

    938730 Allergens of mold and yeast-like fungi

    938760 Food allergens

    938770 Pollen allergens

    938380 Anatoxins and toxins

    938820 Viral and rickettsial antigens and diagnostics

    938830 Antigens and diagnostics bacterial,

    protozoa and other

    938610 Bacteriophages against intestinal infections

    therapeutic and prophylactic

    938620 Bacteriophages against the coccal group of bacteria

    therapeutic and prophylactic

    938630 Diagnostic bacteriophages

    938390 Vaccines, toxoids, toxins and other medicinal –

    prophylactic bacterial preparations

    938370 Inactivated viral vaccines

    938340 Associated bacterial vaccines

    938360 Live viral vaccines

    938300 Bacterial live preventive vaccines

    938330 Bacterial inactivated medicinal vaccines

    938320 Bacterial chemical and vaccines

    inactivated prophylactic

    938350 Rickettsial vaccines

    938890 Diagnosticums, antigens, test – systems,

    used in medicine

    938810 Erythrocyte diagnostics

    938150 Homologous immunoglobulins against viral


    938130 Homologous antibacterial immunoglobulins

    938560 Nutrient bases and growth stimulants, starters

    938170 Other blood preparations and obtained by the method

    genetic engineering

    938190 Preparations from other biological substrates

    938960 Sera, antibodies and immunoglobulins


    938970 Serums and antibodies against blood components

    human and other from human blood

    938980 Other sera and antibodies from animal blood

    938110 Antitoxic sera

    938920 Sera, immunoglobulins and caogglutinating agents

    shigellosis reagents

    938930 Serum and immunoglobulins of Escherichiosis and others

    pathogens of intestinal infections

    938940 Sera for diagnostics of viral diseases

    938950 Serum for identification of other pathogens


    938910 Salmonella sera

    938140 Other sera

    938590 Biological raw materials for virological

    culture media

    938510 Differential diagnostic media

    938540 Media for the isolation and cultivation of other


    938520 Media for the isolation and accumulation of microbes

    intestinal and coccal groups

    938530 Media for differential diagnosis

    pathogens of intestinal infections

    938550 Bacteriological nutrient media and bases


    938580 Virological media and solutions

    938840 Test – systems for the diagnosis of viral infections

    938880 Test – systems for diagnostics of other

    infectious diseases

    938990 Other diagnostic preparations

    938313 BCG vaccine “Immuron”

    938393 Bifidumbacterin

    938231 Interferon alpha

    938231 Interferon beta

    (codes 938313, 938393, 938231, 938231 were introduced by Decree

    of the Government of the Russian Federation of 20.05.99 N 546)

    Immunological preparations

    (introduced by the Decree of the Government of the Russian Federation of 17.07.96 N 822)

    You can view the full text of the document in the commercial version of ConsultantPlus.

    Total thyroxine (T4): research in the laboratory KDLmed

    Thyroxine (T4) is one of the two main thyroid hormones, the main function of which is the regulation of energy and plastic metabolism in the body. Total thyroxine is the sum of two fractions: bound and not bound to blood plasma proteins.

    Synonyms Russian

    Total T4, tetraiodothyronine.

    English synonyms

    Thyroxine, Total T4, Free T4.

    Research method

    Immunochemiluminescence analysis.


    Nmol / L (nanomole per liter).

    Which biomaterial can be used for research?

    Venous blood.

    How to properly prepare for the study?

    1. Do not eat for 2-3 hours before the test, you can drink clean non-carbonated water.
    2. Avoid taking steroid and thyroid hormones 48 hours before the study (in consultation with your doctor).
    3. Eliminate physical and emotional stress 24 hours before the study.
    4. Do not smoke for 3 hours prior to examination.

    General information about the study

    In the course of the study, the concentration in the blood of a fraction of the main thyroid hormone, thyroxine, bound and not bound to proteins, is determined. This is one of the most important tests for assessing the function of the thyroid gland, however, its results depend on the amount of proteins that bind thyroxine in the blood plasma, which does not allow determining the concentration of the biologically active fraction of the hormone.The main proteins that bind thyroxine in the blood plasma are albumin. The ratio of the free and bound fraction of thyroxine and, indirectly, the activity of the hormone, depend on their quantity. Thyroxine makes up about 90% of the total amount of hormones secreted by the thyroid gland.

    Most often, this analysis is prescribed in conjunction with the study of the concentration of thyroid-stimulating hormone – a regulator of the thyroid gland function and the free fraction of thyroxine.

    The thyroid gland controls the metabolism and the intensity of energy consumption by the body.It works by a feedback mechanism with the pituitary gland. The pituitary gland secretes thyrotropin (TSH) in response to a decrease in thyroxine concentration, thereby stimulating the thyroid gland to produce hormones. When the level of thyroxine rises, the pituitary gland begins to produce less thyroid-stimulating hormone and the secretion of the thyroid gland thyroxine decreases.

    If the thyroid gland is unable to produce enough thyroxine or thyroid-stimulating hormone to stimulate it, it is not produced enough, symptoms of hypothyroidism appear.In such patients, the body weight increases, the skin dries, fatigue increases, they become very sensitive to the cold, and the menstrual cycle is disturbed in women. When the thyroid gland secretes increased amounts of thyroxine, metabolic processes in the body and the production of energy in cells are increased, which leads to hyperthyroidism. Heart palpitations, anxiety, weight loss, sleep disturbances, trembling hands, dry and red eyes, swelling of the face are the main symptoms of this disease.

    The most common cause of thyroid hormone imbalance autoimmune lesions of the gland.The most common of them are Graves’ disease (causes hyperthyroidism) and Hashimoto’s thyroiditis (hypothyroidism). Complications of hyper- and hypothyroidism are thyroid cancer, thyroiditis. The influence of these diseases on the function of the thyroid gland can be elucidated by testing for thyroxine.

    What is the research used for?

    • For the diagnosis of thyroid dysfunction.
    • For monitoring the treatment of thyroid diseases.
    • For diagnosing the causes of female infertility.
    • For the diagnosis of congenital hypothyroidism.

    When is the study scheduled?

    • With symptoms of hypo- or hyperthyroidism. Symptoms of hyperthyroidism: heart palpitations, increased irritability, weight loss, insomnia, hand tremors, weakness, fatigue, diarrhea (in some cases), increased sensitivity to light, blurred vision, puffiness around the eyes, dryness, redness, exophthalmos (“ protrusion “of the eyeballs).Symptoms of hypothyroidism: weight gain, dry skin, constipation, cold intolerance, edema, hair loss, irregular menstruation in women. With severe hypothyroidism, complications such as heart rhythm disturbances, ischemia of the heart muscle, coma may occur. In children, hypothyroidism can cause a delay in physical and mental development – cretinism.
    • As part of a preventive examination, together with other laboratory tests (general blood and urine tests, various biochemical parameters).
    • Periodically, when monitoring the treatment of thyroid diseases (together with the analysis for thyroid-stimulating hormone) – at least once every 3 months.
    • During pregnancy, women who have a predisposition to diseases of the thyroid gland or are already suffering from them – for the timely detection of violations of the secretion of thyroid hormones, as they can lead to termination of pregnancy or congenital abnormalities in the fetus.
    • In the first days of life, babies born to mothers with thyroid diseases.

    What do the results mean?

    Reference values ​​

    Age Reference values ​​
    69.6 – 219 nmol / L
    4 months – 1 year 73.0 – 206 nmol / L
    1 – 7 years 76.6 – 189 nmol / L
    7 – 12 years old 77.1 – 178 nmol / L
    12 – 20 years old 76.1 – 170 nmol / L
    > 20 years 66 – 181 nmol / L

    Reasons for increasing the level of T4:

    • diffuse toxic goiter,
    • thyroiditis,
    • thyroid adenoma,
    • TSH-independent thyrotoxicosis,
    • obesity,
    • postpartum thyroid dysfunction,
    • kidney disease,
    • Chronic liver pathology (hepatitis, cirrhosis, etc.)),
    • heparin therapy.

    Reasons for lowering the level of T4:

    • primary hypothyroidism,
    • endemic goiter,
    • autoimmune thyroiditis,
    • resection of the thyroid gland,
    • secondary hypothyroidism,
    • thyrotropinoma,
    • inflammatory processes in the pituitary gland and hypothalamus,
    • iodine deficiency,
    • protein deficiency (depletion),
    • lead poisoning,
    • heroin addiction,
    • taking oral contraceptives.

    What can influence the result?

    • The following drugs can increase thyroxine levels: amiodarone, levothyroxine, propranolol, propylthiouracil, aspirin, danazol, furosemide, tamoxifen, valproic acid.
    • Anabolic steroids, phenytoin, carbamazepine, thyreostatics, clofibrate, lithium preparations, methadone, octreotide.

    Also recommended

    Who orders the study?

    Endocrinologist, therapist, pediatrician, gynecologist, neurologist, surgeon.

    90,000 oral levothyroxine and aspirin-caffeine oral drug interactions – RxList

    oral levothyroxine brand names and other general formulations include:

    levothyroxine 137 mcg tablets side effects

    Eltroxin Oral, Estre Oral, Estue Oral, Euthyrox Oral, Levo-T Oral, Levotabs Oral, Levothroid Oral, Levoxine Oral, Levoxyl Oral, L-thyroxine oral, L-thyroxine sodium oral, Synthrox Oral, Synthith Oral

    All common drug interactions for oral levothyroxine (listings will include brand names and generic names):

    • 2 contraindicated drug interactions
    • 10 serious drug interactions
    • 68 significant drug interactions
    • 56 minor drug interactions

    Aspirin-Caffeine Oral Brand Names and Other Common Formulations Include:

    AA&C Oral, Oral Adult Pain Relief, Oral Strong Adult Pain Relief, Oral Strong Adult Pain Relief, Oral Strong Adult Pain Relief flax, oral anacin maximum strength, oral anacin, oral pain reliever (aspirin / caffeine), oral analgesic for adults potent oral, oral anaprine, arthritis pain reliever (ACA-caffeine) oral, As-Caff oral, oral aspirinaf, oral aspirinaf compound plus oral, oral back and body pain reliever, oral Bayer aspirin (with caffeine), oral Bayer back and body, BC Arthritis oral, Biocin oral, Biosan-M oral, CP-2 oral, fast-acting oral pain reliever, Gensan oral, Majorcin oral, Mejoral W / oral aspirin, PAC oral analgesic, PAC oral, pain reliever, rapid-acting oral, analgesic (aspirin-caffeine) oral, Q-Acin Oral, Stanback Oral, Uni-Ann Oral

    All common drug interactions for aspirin caffeine oral (listings will include brand and generic names):

    • 8 contraindicated drug interactions
    • 9 serious drug interactions
    • 507 significant drug interactions
    • 318 minor drug interactions

    INTERACTIONS CANNOT BE DISPLAYED AT THIS TIME; at MNI.Service.Models.ServiceProviders.ArticleType.RxDrugCheckerServiceProvider.GetInteractionDetails (Int32 iGenericID1, String sGeneric1, Int32 iGenericID2, String sGeneric2, String sTemplate MNI MFSNervice000 extra string sTemplate MNI MFSNervicer.ln. interactions with the Drug Interaction Tester

    Check Now

    Drug Interaction Categories


    Never use this drug combination due to the high risk of hazardous interactions.


    Potential for serious interaction; requires regular monitoring by your physician or alternative medications may be required


    Potential for significant interactions (likely to be monitored by your physician)


    Unlikely, minor, or negligible interactions

    Disclaimer: information contained in this document should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other healthcare provider.