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Vit d2 1.25: Ergocalciferol (Vitamin D2) Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing

Ergocalciferol (Vitamin D2) Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing

Take vitamin D by mouth as directed. Vitamin D is best absorbed when taken after a meal but may be taken with or without food. Alfacalcidol is usually taken with food. Follow all directions on the product package. If you have any questions, ask your doctor or pharmacist.

If your doctor has prescribed this medication, take as directed by your doctor. Your dosage is based on your medical condition, amount of sun exposure, diet, age, and response to treatment.

If you are using the liquid form of this medication, carefully measure the dose using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose.

If you are taking the chewable tablet or wafers, chew the medication thoroughly before swallowing. Do not swallow whole wafers.

If you are taking the rapidly-dissolving tablets, dry your hands before handling the medication. Place each dose on the tongue, allow it to dissolve completely, and then swallow it with saliva or water. You do not need to take this medication with water.

Certain medications (bile acid sequestrants such as cholestyramine/colestipol, mineral oil, orlistat) can decrease the absorption of vitamin D. Take your doses of these medications as far as possible from your doses of vitamin D (at least 2 hours apart, longer if possible). It may be easiest to take vitamin D at bedtime if you are also taking these other medications. Ask your doctor or pharmacist how long you should wait between doses and for help finding a dosing schedule that will work with all your medications.

Take this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day if you are taking it once a day. If you are taking this medication only once a week, remember to take it on the same day each week. It may help to mark your calendar with a reminder.

If your doctor has recommended that you follow a special diet (such as a diet high in calcium), it is very important to follow the diet to get the most benefit from this medication and to prevent serious side effects. Do not take other supplements/vitamins unless ordered by your doctor.

If you think you may have a serious medical problem, get medical help right away.

It’s Time to Say “Goodbye” to Vitamin D2 (ergocalciferol)

In the United States, vitamin D supplementation is primarily available as vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Although these two have historically been considered interchangeable and equipotent, the current body of literature strongly supports the preference of Vitamin D3 (cholecalciferol) over D2 (ergocalciferol).

Vitamin D2 versus Vitamin D3

Vitamin D3 (cholecalciferol) is produced by the human body in response to sunlight and is also available through dietary sources, such as fish. In contrast, vitamin D2 (ergocalciferol) is not produced in the human body, but is created by exposing certain plant-derived materials to ultraviolet light.

When the manufacturing method for ergocalciferol was created, binding studies of the vitamin D receptor in rats showed equipotency between ergocalciferol and cholecalciferol. On the basis of this animal data, most resources cite the two being equipotent and interchangeable.

Given that both ergocalciferol and cholecalciferol undergo metabolic changes in the human body, which differ from other animals, it should make sense that a binding study in rats may not be sufficient to show equivalence. In fact, recent literature (Trang 1998, Armas 2004, Houghton 2006) convincingly demonstrates that cholecalciferol is 1.7 to 3 times more potent and has a longer-lasting effect than ergocalciferol in increasing serum 25-hydroxyvitamin D levels, the active form of vitamin D in humans. The difference in duration of effect and potency are well demonstrated in a study by Armas et al:

Healthy volunteers were given a single 50,000 unit dose of either vitamin D2 (ergocalciferol) or vitamin D3 (cholecalciferol)

Why is ergocalciferol prescribed?

If ergocalciferol is less potent and has a shorter duration of effect, why is it used? The most likely reason is due to dosage formulations. Unlike cholecalciferol, which is typically only available as a maximum dose of 5,000 units per capsule or tablet, ergocalciferol is available as a monster 50,000 unit dose. This larger dose may be seen as more convenient for patients or healthcare providers who want to provide supplementation on a weekly or monthly basis.

Surrogate versus Clinical Outcomes

Although 25-hydroxyvitamin D levels are a better surrogate than a rat binding study, clinical outcomes are the most relevant. Low levels of 25-hydroxyvitamin D (less than 20 ng/mL; Bjelakovic 2014) are very common in North America and have been associated with a wide variety of diseases including osteoporosis, bone fractures, malignancy, cardiovascular disease, infections, and more. The majority of the data supports association, not causation, of low vitamin D levels. In other words, much of the data does not clearly support the idea that vitamin D supplementation in a patient with low vitamin D levels reduces the risk of these diseases.

With that said, a recent Cochrane review (Bjelakovic 2014) analyzed the all-cause mortality benefit of vitamin D supplementation (both D2 and D3) by pooling 95,286 participants from 56 randomized clinical trials. In this meta-analysis, about 80% of participants received cholecalciferol (median dose 800 units/day) and about 20% received ergocalciferol (median 1000 units/day). The vast majority were women (77%), and most were older than 70 years of age.

The Cochrane review calculated an all-cause mortality relative risk (RR) of 0.97 (95% CI 0.94-0.99, p=0.02), which represented a raw difference in mortality of 12.5% (control) vs. 12.7% (vitamin D). The authors calculated a number needed to treat (NNT) of 150 over five years; however, the NNT calculates to 500 over a weighted mean of 4.4 years using the raw difference in mortality rates. Importantly, the difference in mortality was only demonstrated for trials examining cholecalciferol. Although ergocalciferol did make up a minority of the meta-analysis, it was adequately powered to detect a 5% difference in relative risk reduction.


  1. Cholecalciferol (vitamin D3) is more potent and longer acting than ergocalciferol (vitamin D2) as measured by the active form of vitamin D in the blood (25-hydroxyvitamin D).
  2. Low vitamin D levels are common in North America; most data supports an association between low vitamin D levels and disease. Much less data supports a cause-and-effect relationship between vitamin D supplementation and prevention of specific diseases.
  3. Vitamin D supplementation with cholecalciferol (D3) appears to have a small but statistically significant benefit in improving all-cause mortality among elderly women. The mortality benefit in younger patients or male patients is not clear.
  4. Ergocalciferol (D2) is less studied than cholecalciferol and was not shown to confer a mortality benefit in a recent Cochrane meta-analysis despite adequate statistical power.
  5. For patients who meet criteria for vitamin D supplementation (which is an entire argument in itself), vitamin D3 (cholecalciferol) should be selected over vitamin D2 (ergocalciferol).


  1. Armas LA, Hollis BW, Heaney RP. Vitamin D2 is much less effective than vitamin D3 in humans. J Clin Endocrinol Metab. 2004 Nov;89(11):5387-91. PMID 15531486.
  2. Trang HM, Cole DE, Rubin LA, et al. Evidence that vitamin D3 increases serum 25-hydroxyvitamin D more efficiently than does vitamin D2. Am J Clin Nutr. 1998 Oct;68(4):854-8. PMID 9771862
  3. Houghton LA, Vieth R. The case against ergocalciferol (vitamin D2) as a vitamin supplement. Am J Clin Nutr. 2006 Oct;84(4):694-7. PMID 17023693.
  4. Bjelakovic G, Gluud LL, Nikolova D, et al. Vitamin D supplementation for prevention of mortality in adults. Cochrane Database Syst Rev. 2014 Jan 10;1:CD007470. PMID 24414552.

Weekly And Biweekly Vitamin D2 Prevents Vitamin D Deficiency — ScienceDaily

Boston University School of Medicine researchers (BUSM) have found that 50,000 International Units (IU) of vitamin D2, given weekly for eight weeks, effectively treats vitamin D deficiency. Vitamin D2 is a mainstay for the prevention and treatment of vitamin D deficiency in children and adults. Continued treatment with the same dose of vitamin D2 every other week for up to six years after the initial eight-week period prevents vitamin D deficiency from recurring with no toxicity.

The BUSM study appears online in the journal Archives of Internal Medicine.

Vitamin D is essential for strong bones because it helps the body absorb calcium and phosphorus from the food we eat. Vitamin D deficiency can lead to rickets in children and the painful bone disease osteomalacia in adults. Vitamin D deficiency can also cause osteoporosis and has been linked to increased risk of cancer, heart disease, diabetes, autoimmune diseases and infectious diseases including influenza, according to senior author Michael F. Holick, PhD, MD, director of the Bone Healthcare Clinic and the Vitamin D, Skin and Bone Research Laboratory at Boston University School of Medicine.

Of the 86 patients researchers studied, 41 patients who were vitamin D deficient received eight weeks of 50,000 IU of vitamin D2 weekly prior to starting maintenance therapy. For those patients, the mean pre-treatment 25-hydroxyvitamin D status (25(OH)D) level was 19 ng/ml, which increased to 37 ng/ml after eight weeks of weekly therapy. These patients were then treated with 50,000 IU of vitamin D2 every other week and had a mean final 25(OH)D level of 47 ng/ml.

For the 45 patients who received only maintenance therapy of 50,000 IU of vitamin D2 every two weeks, the mean pre-treatment 25(OH)D level was 27 ng/ml and the mean final level was 47 ng/ml.

“Vitamin D2 is effective in raising 25(OH)D levels when given in physiologic and pharmacologic doses and is a simple method to treat and prevent vitamin D deficiency,” said Holick, who is also director of the General Clinical Research Unit and professor of medicine, physiology and biophysics at BUSM. “While treating and preventing vitamin D deficiency, these large doses of vitamin D2 do not lead to vitamin D toxicity.”

According to Holick, this is the first study demonstrating the efficacy of a prescription therapy to prevent vitamin D deficiency longterm in routine clinical practice.

Quest Diagnostics, the nation’s leading provider of diagnostics testing, information and services, analyzed the specimens used in the study.

Story Source:

Materials provided by Boston University Medical Center. Note: Content may be edited for style and length.

Why would I need a vitamin D prescription?

It’s that time of year when much of the United States experiences dreary weather and less time in the sun. When it comes to your health, many people tend to associate winter weather with the flu or the common cold. But there is an important nutrient that many of us are missing out on, especially in the wintertime, and it plays a big role in your bone health: vitamin D.

What is vitamin D?

“Vitamin D is a fat soluble vitamin that is needed for calcium to be absorbed into your bones,” says Dr. Inna Lukyanovsky, Pharm.D., functional medicine practitioner and the author of The Crohn’s and Colitis Fix.

Chirag Shah, MD, co-founder of Push Health, elaborates: “Vitamin D is a type of molecule known as a secosteroid. Vitamin D is biologically active in the body and helps increase the absorption of electrolytes, including calcium and magnesium, from the gastrointestinal tract.”  

In other words, your bones can’t absorb calcium without vitamin D. That’s why most cow’s milk sold in U.S. grocery stores is fortified with vitamin D. No matter how much of that great calcium you get from foods, your bones will be soft and brittle unless you also take in enough vitamin D to process it. 

Why would a doctor prescribe vitamin D?

Vitamin D prescriptions might be on the rise. One study found that testing for vitamin D deficiencies and subsequent prescriptions of the fat soluble vitamin increased more than sevenfold between 2008 and 2013. Why the huge increase? Researchers believe that it was due to a global increase in awareness of patients who are vitamin D deficient, rather than an actual increase in need.  

So why would a doctor prescribe vitamin D supplementation? There are several reasons, but it starts with the vitamin’s accessibility. 

Where do we get vitamin D?

“Vitamin D is obtained from few food sources in any significant quantity (liver, wild caught salmon, and minimal amounts in fortified milk),” says Arielle Levitan, MD, co-founder of Vous Vitamin and author of The Vitamin Solution. “It can be obtained from exposure to the sun.” 

But a lot of people don’t get enough vitamin D from food or sun exposure. If that’s the case, they might need to take a vitamin D supplement. Sometimes people can get what they need from an over-the-counter (OTC) supplement, but many people need a prescription from their doctor. You can find generic vitamin D supplements in pharmacies and drugstores as well as brand-name supplements such as Drisdol and Calciferol.

Medical conditions that require vitamin D prescription

“Vitamin D is commonly prescribed for hypoparathyroidism [a condition that causes calcium deficiency, muscle cramps and spasms, weakness, and fatigue],” says Dr. Lukyanovsky. “Doctors might also prescribe it for osteomalacia, a condition where there’s a depletion of calcium from the bone.” 

There are other medical conditions that might necessitate a vitamin D prescription. For example, hypocalcemia is a condition that is marked by insufficient calcium in the blood. Doctors treat it with specific types of vitamin D called alfacalcidol, calcifediol, calcitriol, and dihydrotachysterol. Alfacalcidol, calcifediol, and calcitriol are also prescribed for the treatment of certain types of bone disease that are common in kidney dialysis patients.

Vitamin D deficiency

All of our medical experts tell us that one of the most common reasons for prescribing vitamin D is a deficiency of it. If a patient is experiencing symptoms of vitamin D deficiency, such as bone loss, hair loss, bone and back pain, and difficulty healing from wounds, their healthcare provider will most likely order a lab test to confirm vitamin D deficiency. 

Blood levels of 20 nanograms/milliliter to 50 ng/mL of vitamin D is considered within normal range for healthy people. If the lab results show a low vitamin D level that’s below 12 ng/mL, that indicates a vitamin D deficiency.

Vitamin D deficiency is very serious. If the amount of vitamin D in the blood is too low, it can cause a condition called Rickets in children. Rickets is a rare disease. It causes children’s bones to become soft and bend, sometimes forming “bow legs.” African American children are at highest risk of getting rickets. 

As mentioned above, adults can also suffer medical consequences from not enough vitamin D, including the bone disease osteomalacia.

Some doctors think vitamin D could be connected to more medical conditions, like high blood pressure, diabetes, cancer, and multiple sclerosis. Researchers are studying potential links, but more research is needed before we can truly understand the relationship between vitamin D and these conditions. 

Populations at special risk for vitamin D deficiency

There are some people who are particularly vulnerable to vitamin D deficiency, and they might need to take over-the-counter or prescription supplements even without symptoms.  

  • Breastfed infants: Vitamin D is not present in significant amounts in human breast milk, and the American Academy of Pediatrics recommends against exposing infants to direct sunlight without sunscreen. This means these babies are at risk of a vitamin D deficiency, and possibly Rickets. They should take a dietary supplement of 400 international units (IU) of vitamin D per day. 
  • Older adults: In old age, the skin is less able to absorb vitamin D from the sun. 
  • Pregnant women: During pregnancy, some women are at increased risk of vitamin D deficiency. Taking a daily vitamin D supplement of 4,000 IU during pregnancy might reduce the risk of gestational diabetes and early labor.
  • People who are obese: Their body fat can bind to some vitamin D and prevent it from getting to the blood.
  • People who have had gastric bypass surgery.
  • People with osteoporosis, kidney disease, or liver disease.
  • People with dark skin: The higher amounts of skin pigmentation make it more difficult to produce vitamin D from sunlight. 
  • People with Crohn’s disease or celiac disease: These disorders cause the body to have difficulty handling fat, which is needed in order to absorb this fat soluble vitamin.
  • People with hyperparathyroidism: This means that their bodies have too much of the parathyroid hormone, which controls the body’s calcium level.
  • People who take certain medicines: Some medications, such as cholestyramine, anti-seizure drugs, glucocorticoids, HIV/AIDS medications, and antifungal drugs, can affect your body’s metabolism of vitamin D. 

Vitamin D2 vs. D3

Did you know that vitamin D actually comes in multiple forms? The two most important forms of vitamin D for your health are D2 and D3. 

“Vitamin D2 is known as ergocalciferol while vitamin D3 is known as cholecalciferol,” says Dr. Shah. “Vitamin D2 typically originates from plant-based sources while vitamin D3 is generally found in animal sources.”

And we’re not just talking food here. Remember, humans are animals, too. So the vitamin D that your skin absorbs from the sun is the D3 form.

Dr. Levitan says that people who need vitamin D supplements should take D3. This is the most active form of vitamin D in your body, as the liver converts D2 to D3. Though most people can easily metabolize D2 as well. 

What is prescription-strength vitamin D?

We’ve been talking a lot about vitamin D prescriptions. But the truth is, many doctors “prescribe” their patients to take over-the-counter vitamin D supplements. Higher doses of OTC supplements are available in 400 IU, 800 IU, 1000 IU, 2000 IU, 5000 IU, and 10,000 IU tablets and liquid drops. 

Prescription strength vitamin D contains a high dose of 50,000 IU. But our experts say that this dose is not necessary for most people.

“The best way to take vitamin D is via a daily year-round dose through a personalized vitamin regimen,” says Dr. Levitan. “The amount each individual needs varies based on who you are, where you live, ethnicity, medical issues and more. There are ‘mega dose’ prescription products of D3, which can be taken weekly in tablet form. However, these are rarely needed other than in extreme cases and in people with GI absorption issues (I.e., Crohn’s disease). Ultimately most people can maintain a normal vitamin D level with a daily dose between 800 and 2000 IU daily.  This can be taken in tablet, capsule, or drop forms. The best way to get exactly what you need is to take a doctor-created custom regimen to meet your exact vitamin needs.” 

Vitamin D side effects and interactions

According to Dr. Lukyanovsky, the following are potential side effects of vitamin D supplements:

  • Bone pain
  • Muscle weakness
  • Nausea, vomiting, or constipation
  • Extreme thirst
  • Frequent urination
  • Kidney stones
  • Confusion or disorientation
  • Weight loss or poor appetite
  • Fatigue

Dr. Lukyanovsky explains that Vitamin D supplements can also negatively interact with certain medications, so talk to your doctor before taking them if you are also taking any of these drugs.

  • Diabetes medicines
  • Blood pressure medicines
  • Calcium supplements
  • Antacids
  • Corticosteroids, such as prednisone
  • Weight-loss medicines, including Alli (orlistat)
  • Questran, LoCholest, or Prevalite (cholestyramine)
  • Seizure medicines, including phenobarbital and Dilantin (phenytoin)

It’s possible to consume too much vitamin D. If your daily intake of vitamin D far exceeds the recommended dietary allowance (RDA) can lead to vitamin D toxicity, which causes build up of calcium in the blood (hypercalcemia), nausea, and vomiting.  

As with any medications, you should always seek medical advice from your healthcare provider before you take a vitamin D supplement, even if it’s over-the-counter. Not only is it possible for the supplements to interact with other medications you are taking, or affect conditions you might have, but you need to know the right dose of vitamin D for you, too.  

Ergocalciferol (Vitamin D2) tablets, capsules and solution for oral use

Ergocalciferol (Vitamin D2) tablets, capsules and solution

Active Ingredient


Administration Route


Alcohol Warning

No known interactions.

Available Strength

Capsule, Oral:

1.25 mg (50000 UT)

62.5 mcg (2500 UT)

Solution, Oral:

200 mcg/mL (60 mL)

Tablet, Oral:

10 mcg (400 UT), 50 mcg (2000 UT)

Breastfeeding Warning

Caution is recommended. It is excreted into human milk.

-Large maternal doses of vitamin D led to hypercalcemia in a child.
-Monitoring of the infant’s serum calcium may be needed.
-The US Recommended Daily Allowance for lactating women is 600 international units per day.

Clinical Pharmacology


After the activation of the vitamin D receptor, some of the biological changes produced by ergocalciferol include mobilization and accretion of calcium and phosphorus in the bone, absorption of calcium and phosphorus in the intestine, and reabsorption of calcium and phosphorus in the kidney.

Some other effects known to be produced due to the presence of vitamin D are osteoblast formation, fetus development, induction of pancreatic function, induction of neural function, improvement of immune function, cellular growth and cellular differentiation.

When compared to its vitamin D counterpart cholecalciferol, ergocalciferol has been shown to present a reduced induction of calcidiol and hence, it is less potent.

Ergocalciferol supplementation in patients with end-stage renal disease has been shown to generate a significant benefit in lab parameters of bone and mineral metabolism as well as improvement in glycemic control, serum albumin levels and reduced levels of inflammatory markers


Onset of action: 10 to 24 hours; Maximum effect: ~1 month following daily doses

Absorption: Absorbed in the small intestine; fat soluble; requires bile

Metabolism: Inactive until hydroxylated hepatically to 25-hydroxyvitamin D [25(OH)D; calcifediol] then renally to the active metabolite 1,25-dihydroxyvitamin D (calcitriol)

Half-life, circulating: 25(OH)D: 2 to 3 weeks; 1,25-dihydroxyvitamin D ~4 hours

Excretion: Feces


Capsules (Drisdol Oral):

1.25 MG(50000 UT) (per each): $3.49

Capsules (Ergocalciferol Oral)

1.25 MG(50000 UT) (per each): $0. 72

Solution (Calcidol Oral)

200 mcg/mL (per mL): $1.66

Solution (Calciferol Oral)

200 mcg/mL (per mL): $3.44

Solution (Ergocalciferol Oral)

200 mcg/mL (per mL): $0.59 – $1.67

Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer’s AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.

Dosage Form

Capsules, Solution and Tablets for oral administration

Dose Schedule

Osteoporosis prevention (off-label use): Oral: Adults ≥50 years of age: 800 to 1,000 units/day

Vitamin D insufficiency/deficiency treatment (off-label use):  Repletion strategies may vary depending on desired target serum 25(OH)D levels as well as the clinical status of the patient. The optimal serum 25(OH)D level is controversial; the Institute of Medicine recommends a 25(OH)D level >20 ng/mL as sufficient in nearly all persons, whereas others have suggested targeting a level of ~30 ng/mL to minimize the risk of fractures, particularly in patients with. However, some data suggest levels >40 ng/mL (median level in one trial: ~48 ng/mL) are associated with increased risk of falls in postmenopausal women.

Therefore, some experts recommend a range of 20 to 40 ng/mL as a reasonable target in most patients. Ergocalciferol (vitamin D2) is considered an alternative agent to the use of cholecalciferol (vitamin D3) by some experts due to limited data showing slightly higher levels of serum 25(OH)D achieved with D3, especially when higher doses or longer intervals are used. In patients with normal absorption, for every 100 units/day of vitamin D ingested the serum 25(OH)D level is expected to increase by ~0.7 to 1 ng/mL. The dose-response declines as the 25(OH)D concentration increases above 40 ng/mL (100 nmol/L). The following recommendations are based primarily on expert opinion and clinical experience:

Initial dosing (according to baseline serum 25(OH)D level):

Serum 25(OH)D 20 to 30 ng/mL: Initial: Supplementation dosing: Oral: 600 to 800 units once daily; a repeat serum 25(OH)D level is not required or 1,000 to 2,000 units once daily; may consider a repeat serum 25(OH)D level in ~3 months to determine if the target level has been achieved.

Serum 25(OH)D 10 to <20 ng/mL: Initial:Supplementation dosing: Oral: 800 to 1,000 units once daily or 2,000 units once daily; a repeat serum 25(OH)D level should be drawn after ~3 months. If target serum 25(OH)D level has not been achieved, may increase to 2,000 units once daily or administer therapeutic dosing of 50,000 units once weekly for 6 to 8 weeks.


Therapeutic dosing (ie, high-dose ergocalciferol): Oral: 50,000 units once weekly (or 5,000 to 7,000 units once daily) for ~8 weeks followed by decreased maintenance dosing as needed to maintain target serum 25(OH)D level.

Serum 25(OH)D <10 ng/mL or in patients with deficiency symptoms : Initial: Therapeutic dosing (ie, high-dose ergocalciferol): Oral: 50,000 units once weekly (or 5,000 to 7,000 units once daily) for 6 to 8 weeks to achieve target serum 25(OH)D level; a repeat serum 25(OH)D level should be drawn after ~3 months to assure target serum 25(OH)D level has been met.

Maintenance dosing: Maintenance dosing is highly patient specific and dependent on target 25(OH)D level and may range from 600 to 800 units/day to 1,000 to 2,000 units/day

Special populations (eg, obese patients, patients on medications known to affect vitamin D metabolism, patients with malabsorption syndromes or gastrectomy): Higher doses or longer durations may be necessary for adequate repletion.

Vitamin D deficiency/insufficiency in patients with chronic kidney disease (off-label use): 

In patients without severe and progressive hyperparathyroidism, including chronic kidney disease (CKD) stages G3 to G5 and dialysis or transplant patients, KDIGO guidelines recommend correcting vitamin D deficiency and insufficiency with treatment strategies recommended for the general population using ergocalciferol (or cholecalciferol) while avoiding hypercalcemia and ensuring phosphate levels are in the normal range. An individualized monitoring approach to direct treatment is also recommended. In patients in whom serum parathyroid hormone levels are progressively rising and remain persistently elevated despite correction of modifiable factors (eg, hyperphosphatemia, vitamin D deficiency), calcitriol or vitamin D analogs are suggested instead of ergocalciferol (or cholecalciferol).

Hypoparathyroidism: Active vitamin D preparations (ie, alfacalcidolcalcitriol) in conjunction with calcium supplementation are recommended therapy. Addition of ergocalciferol (or cholecalciferol) may be considered for supplemental therapy.

Drug Class

A11CC — Vitamin D and analogues

Drug Unit

mg, mcg, IU, UT,  USP units

Food Warning

No known interactions with food.

Included In
Health Insurance Plan

In general, Medicare plans do not cover this drug.

Interacting Drugs

Aluminum Hydroxide: Vitamin D Analogs may increase the serum concentration of Aluminum Hydroxide. Specifically, the absorption of aluminum may be increased, leading to increased serum aluminum concentrations. Risk X: Avoid combination

Bile Acid Sequestrants: May decrease the serum concentration of Vitamin D Analogs. More specifically, bile acid sequestrants may impair absorption of Vitamin D Analogs. Management: Avoid concomitant administration of vitamin D analogs and bile acid sequestrants (eg, cholestyramine). Separate administration of these agents by several hours to minimize the potential risk of interaction. Monitor plasma calcium concentrations. Risk D: Consider therapy modification

Calcium Salts: May enhance the adverse/toxic effect of Vitamin D Analogs. Risk C: Monitor therapy

Cardiac Glycosides: Vitamin D Analogs may enhance the arrhythmogenic effect of Cardiac Glycosides.  Risk C: Monitor therapy

Danazol: May enhance the hypercalcemic effect of Vitamin D Analogs. Risk C: Monitor therapy

Erdafitinib: Serum Phosphate Level-Altering Agents may diminish the therapeutic effect of Erdafitinib. Management: Avoid coadministration of serum phosphate level-altering agents with erdafitinib before initial dose increase period based on serum phosphate levels (Days 14 to 21). Risk D: Consider therapy modification

Mineral Oil: May decrease the serum concentration of Vitamin D Analogs. More specifically, mineral oil may interfere with the absorption of Vitamin D Analogs. Management: Avoid concomitant, oral administration of mineral oil and vitamin D analogs. Consider separating the administration of these agents by several hours to minimize the risk of interaction. Monitor plasma calcium concentrations. Risk D: Consider therapy modification

Multivitamins/Fluoride (with ADE): May enhance the adverse/toxic effect of Vitamin D Analogs.  Risk X: Avoid combination

Multivitamins/Minerals (with ADEK, Folate, Iron): May enhance the adverse/toxic effect of Vitamin D Analogs. Risk X: Avoid combination

Orlistat: May decrease the serum concentration of Vitamin D Analogs. More specifically, orlistat may impair absorption of Vitamin D Analogs. Management: Monitor clinical response (including serum calcium) to oral vitamin D analogs closely if used with orlistat. If this combination must be used, consider giving the vitamin D analog at least 2 hrs before or after orlistat. Risk D: Consider therapy modification

Sucralfate: Vitamin D Analogs may increase the serum concentration of Sucralfate. Specifically, the absorption of aluminum from sucralfate may be increased, leading to an increase in the serum aluminum concentration. Risk X: Avoid combination

Thiazide and Thiazide-Like Diuretics: May enhance the hypercalcemic effect of Vitamin D Analogs. Risk C: Monitor therapy

Vitamin D Analogs: May enhance the adverse/toxic effect of other Vitamin D Analogs.  Risk X: Avoid combination

Is Available Generically


Is Proprietary


Label Details


Legal Status


Is not subject to the Controlled Substances Act.


Strides Pharma Science Limited

Maximum Intake

In healthy patients 4000 IU is the safe upper limit according to the Institute of Medicine, which is needed to maintain optimal blood levels.

Mechanism of Action

For its activity, ergocalciferol is required to be transformed to its major active circulating hydroxylated metabolite and transported to the target organs in order to bind to its target, the vitamin D receptor.

The activation of the vitamin D receptor is part of the vitamin D endocrine system and it is described by the production of a change in the transcription rates of the vitamin D receptor target genes.The target genes in the DNA affected by the presence of ergocalciferol are called vitamin D response elements which are dependent on co-modulators.

The vitamin D receptor is a transcription factor and member of the steroid hormone nuclear receptor family. It presents a DNA binding domain (VDRE) that, when activated, recruits coregulatory complexes to regulate the genomic activity.

Additionally, ergocalciferol presents nongenomic effects such as the stimulation of intestinal calcium transport via transcaltachia.

Non Proprietary Name



Symptoms of overdose may include:

  • loss of appetite
  • nausea
  • weakness
  • weight loss
  • muscle aches and stiffness
  • constipation
  • pale skin
  • increased urination (especially at night) or increased thirst
  • intellectual disability

Pregnancy Category

Safety has not been established during pregnancy. Use only if the benefit outweighs the risk to the fetus.AU TGA pregnancy category: Exempt
US FDA pregnancy category: C

Pregnancy Warning

-Avoid use of vitamin D in excess of the recommended dietary allowance.
-The safety of vitamin D doses in excess of 400 international units has not been established.Animal studies have shown fetal abnormalities associated with hypervitaminosis D, similar to supravalvular aortic stenosis syndrome. There are no controlled data in human pregnancy.AU Exempt: Medications exempted from pregnancy classification are not absolutely safe for use in pregnancy in all circumstances. Some exempted medicines, for example the complementary medicine, St John’s Wort, may interact with other medicines and induce unexpected adverse effects in the mother and/or fetus.US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

Prescribing Info


Prescription Status

Rx and/or OTC

Proprietary Name

Calcidol, Calciferol, Drisdol

Related Drugs

Calcitriol, Calcifediol, Alfacalcidiol, Dihydrotachysterol











Concerns related to adverse effects:

  • Vitamin D toxicity: May occur with excessive doses; symptoms may include nausea, vomiting, loss of appetite, constipation, dehydration, fatigue, irritability, confusion, weakness, and/or weight loss. Effects of vitamin D can last ≥2 months after therapy is discontinued.

Disease-related concerns:

  • Hyperphosphatemia: Normal serum phosphorous concentrations must be maintained in patients treated for hyperphosphatemia to prevent metastatic calcification.
  • Obesity: Adults with a BMI >30 kg/m2are at high risk for vitamin D deficiency due to storage of vitamin D in adipose tissue. Doses higher than the RDA may be required, but must be carefully monitored to avoid toxicity.
  • Renal impairment: Metabolism of vitamin D may be altered in patients with chronic kidney disease. Supplementation with ergocalciferol may be needed; close monitoring is required (KDIGO 2009).

Concurrent drug therapy issues:

  • Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Dosage form specific issues:

  • Propylene glycol: Oral solutions may contain propylene glycol; toxicities may occur if large doses of vitamin D are required. Alternate dosage forms/products should be used .
  • Tartrazine: Products may contain tartrazine, which may cause allergic reactions in certain individuals.

Warnings: Additional Pediatric Considerations

Some dosage forms may contain propylene glycol; in neonates large amounts of propylene glycol delivered orally, intravenously (eg, >3,000 mg/day), or topically have been associated with potentially fatal toxicities which can include metabolic acidosis, seizures, renal failure, and CNS depression; toxicities have also been reported in children and adults including hyperosmolality, lactic acidosis, seizures, and respiratory depression; use caution.

Ergocalciferol: Uses, Interactions, Mechanism of Action


Ergocalciferol is indicated for the treatment of hypoparathyroidism, refractory rickets, and familial hypophosphatemia. Label

Hypoparathyroidism is the result of inadequate parathyroid hormone production that occurs due to the presence of damage or removal of the parathyroid glands. This condition produces decreased calcium and increased phosphorus levels.11

Rickets is a condition produced due to a deficiency in vitamin D, calcium or phosphorus. However, this condition can also be related to renal diseases. It is characterized to present weak or soft bones.4

Familial hypophosphatemia is characterized by the impaired transport of phosphate and an altered vitamin D metabolism in the kidneys. The presence of this condition can derive in the presence of osteomalacia, bone softening and rickets.12

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After the activation of the vitamin D receptor, some of the biological changes produced by ergocalciferol include mobilization and accretion of calcium and phosphorus in the bone, absorption of calcium and phosphorus in the intestine, and reabsorption of calcium and phosphorus in the kidney.7

Some other effects known to be produced due to the presence of vitamin D are osteoblast formation, fetus development, induction of pancreatic function, induction of neural function, improvement of immune function, cellular growth and cellular differentiation. 7

When compared to its vitamin D counterpart cholecalciferol, ergocalciferol has been shown to present a reduced induction of calcidiol and hence, it is less potent.2

Ergocalciferol supplementation in patients with end-stage renal disease has been shown to generate a significant benefit in lab parameters of bone and mineral metabolism as well as improvement in glycemic control, serum albumin levels and reduced levels of inflammatory markers.1

Mechanism of action

For its activity, ergocalciferol is required to be transformed to its major active circulating hydroxylated metabolite and transported to the target organs in order to bind to its target, the vitamin D receptor.7

The activation of the vitamin D receptor is part of the vitamin D endocrine system and it is described by the production of a change in the transcription rates of the vitamin D receptor target genes.7 The target genes in the DNA affected by the presence of ergocalciferol are called vitamin D response elements which are dependent on co-modulators. 3

The vitamin D receptor is a transcription factor and member of the steroid hormone nuclear receptor family. It presents a DNA binding domain (VDRE) that, when activated, recruits coregulatory complexes to regulate the genomic activity.3

Additionally, ergocalciferol presents nongenomic effects such as the stimulation of intestinal calcium transport via transcaltachia.3


Ergocalciferol is absorbed in the intestine and carried to the liver in chylomicrons. Its intestinal absorption does not present limitations unless the presence of conditions related to fat malabsorption.6 However, for absorption to take place, the presence of bile is required.13

Volume of distribution

The amount of circulating ergocalciferol is very limited as this compound is rapidly stored in fat tissue such as adipose tissue, liver and muscle. This is very obvious in reports that indicate that circulating ergocalciferol is significantly reduced in obese patients.6

Protein binding

Ergocalciferol is not found significantly distributed circulating in plasma. It is known to be found in its bound form to the vitamin D plasma protein.9 The parent compound of ergocalciferol does not bind directly to plasma proteins, however, 70-90% of its metabolites such as cholecalciferol and calcitriol are found in the bound form.5


Ergocalciferol is inactive and hence, the first step in the body is ruled by the conversion of this parent compound to 25-hydroxyvitamin D by the action of CYP2R1 followed by the generation of the major circulating metabolite, 1,25-dihydroxyvitamin D or calcitrol.6 The generation of this major metabolite is ruled by the activity of CYP27B1 which is a key 1-hydroxylase and CYP24A1 which is responsible for the 25-hydroxylation.3

As part of the minor metabolism, ergocalciferol is transformed into 25-hydroxyvitamin D in the liver by the activity of D-25-hydroxylase and CYP2R1. As well, the formation of 24(R),25dihydroxyvitamin D is performed mainly in the kidneys by the action of 25-(OH)D-1-hydroxylase and 25-(OH)D-24-hydroxylase.7

Additionally, there are reports indicating significant activity of 3-epimerase in the metabolism of ergocalciferol which modifies the hydroxy group in C3 from the alpha position to a beta. The epimers formed seemed to have a reduced affinity for the vitamin D plasma proteins and to the vitamin D receptor.3

An alternative activation metabolic pathway has been reported and this process is characterized by the activity of CYP11A1 and its hydroxylation in the C-20. This 20-hydroxylated vitamin D seems to have similar biological activity than calcitriol.3

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Route of elimination

The active form of ergocalciferol, calcitrol, cannot be maintained for long periods in storage tissue mainly in periods of dietary or UVB deprivation.6 Therefore, ergocalciferol and its metabolites are excreted via the bile with a minor contribution of renal elimination. This major fecal elimination is explained due to the cubilin-megalin receptor system-mediated renal reuptake of vitamin D metabolites bound to vitamin D binding protein.14


Ergocalciferol can be found circulation for 1-2 days. This quick turnover is presented due to hepatic conversion and uptake by fat and muscle cells where it is transformed to the active form.6


There are no formal reports regarding the clearance rate of ergocalciferol. Due to the structural similarity, it is recommended to consult this parameter with cholecalciferol. On the other hand, the proposed renal clearance of calcitriol is of 31 ml/min.8

Adverse Effects

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The reported LD50 for orally administered ergocalciferol in the rat is of 10 mg/kg.MSDS Overdosage with this agent is reported to produce hypervitaminosis characterized by hypercalcemia, renal impairment, calcification of soft tissues, a decline in the rate of linear growth and increase in bone mineralization.15

Once an overdose state is registered, immediate withdrawal of vitamin D is required along with a calcium diet, generous intake of fluids and symptomatic treatment. The administration of loop diuretics is an option to increase renal calcium excretion. On the other hand, dialysis and administration of citrates, sulfates, phosphates, corticosteroids, EDTA and mithramycin are recommended.15

There haven’t been long term studies analyzing the carcinogenic and mutagenic potential of ergocalciferol or its effects in fertility.

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Pharmacogenomic Effects/ADRs
Not Available
CAS number
InChI Key





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Ergocalciferol (Vitamin D2) combination Price of 9 Brands / Trade Names

Information about drug Ergocalciferol (Vitamin D2) combination includes cost of the drug and the type of drug – tablet, capsule, syrup, cream, gel, ointment, liquid or injection. To view the price of the drug, click on the brand name. The generic Ergocalciferol (Vitamin D2) combination is manufactured by one company. Medindia’s drug directory has currently 9 Brands of Ergocalciferol (Vitamin D2) listed. New generics and brands are constantly being updated as and when they are approved by drug controller and available in the pharmacies.

SNo Brand Name Combination Generics Manufacturers Type Price

Aby Z (15ml)

Biotin, D-Panthenol, Niacinamide, Vit A, Vit B1, Vit B2, Vit B6, Vit C, Vit D2, Vit E, Zinc Gluconate Abs Remedies Pvt. Ltd. Drops View Price

Clazy Forte (1250mg+250iu)

Calcium Carbonate, Vit D2 Zee Laboratories Ltd. Tablet View Price

Dl Calciplex (112ml)

Calcium Gluconate, Calcium Hypophosphate, Calcium Lactate, D-Panthenol, Ferrous Gluconate, L-Lysine, Mag Hypophosphite, Nicotinamide, Sorbitol, Vit A, Vit B12, Vit B2, Vit B6, Vit C, Vit D2 Khandelwal Laboratories Pvt. Ltd. Syrup View Price

Multivitaplex Forte

Calcium Pantothenate, Folic Acid (Vit B9), Niacinamide, Tocopherol, Vit A, Vit B1, Vit B12, Vit B2, Vit B6, Vit C, Vit D2, Vit K Pfizer Limited(Pharmacia India Pvt Ltd) Capsule View Price


Ultirich (100 gm)

Calcium Carbonate, Carbonyl Iron, Folic Acid (Vit B9), Vit D2, Whey Protiens Wallace Pharmaceuticals Ltd. (Lyfestyle) Powder View Price

Ultrich (200 gm)

Calcium Carbonate, Carbonyl Iron, Folic Acid (Vit B9), Vit D2, Whey Protiens Wallace Pharmaceuticals Ltd. (Lyfestyle) Powder View Price

Vitaped (15ml)

L-Lysine, Niacinamide, Riboflavin, Tocopheryl Acetate, Vit A, Vit B1, Vit B6, Vit C, Vit D2 Sunways(India)Pvt. Ltd. Drops View Price

Welcal (500mg+250iu)

Calcium Carbonate, Vit D2 Sigman Wellness Tablet View Price

Wescovita (200 gm)

Caseine Hydrolysate, Di-Calcium Phosphate, Ferric Ammonium Citrate, Folic Acid (Vit B9), Lysine, Niacinamide, Vit A, Vit B12, Vit B6, Vit D2 West Coast Pharmaceuticals Works Powder View Price

90,000 1,25 (OH) 2D3 – 1,25-dihydroxivitamin D3 (1,25-dihydroxivitamin D3)

Method of determination

HPLC-MS (high performance liquid chromatography with mass selective detection). The quantitative assessment is carried out for the 1,25-dihydroxy D3 fraction (the relative content of the 1,25-dihydroxy D2 fraction in the RF population is negligible).

Study material
Blood serum

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Synonyms: 1,25-dihydroxyvitamin D, 1,25-dihydroxyvitamin D3, calcitriol.1,25-dihydroxyvitamin D, 1,25 (OH) 2D, calcitriol.

Brief characteristics of the analyte (1,25-dihydroxyvitamin D3)

Vitamin D is formed in the skin by exposure to sunlight or ingested with food. In this case, two forms are distinguished – D3 (cholecalciferol) and D2 (ergocalciferol). These forms of the vitamin are potentially equivalent, but biologically inert. In the liver, under the action of the enzyme vitamin D 25-hydroxylase, they are converted into 25 (OH) D3 or 25 (OH) D2, which are collectively designated as 25 (OH) D.This is an indicator of total vitamin reserves – this form represents the main part of circulating vitamin D. 25 (OH) D can be converted into the main biologically active form of vitamin – 1.25 (OH) 2D by the action of the enzyme 25 (OH) D1-alpha-hydroxylase. It is in this form that vitamin D binds to cellular receptors and participates in the regulation of the level of calcium and phosphorus in the blood, acting on the intestines, bone tissue, kidneys and parathyroid glands. The formation of 1,25 (OH) 2D occurs predominantly in the kidneys and also in the placenta during pregnancy.

The level of 1.25 (OH) 2D in the blood is tightly controlled, mainly due to the action of parathyroid hormone, phosphate, calcium and the concentration of 1.25 (OH) 2D itself. Parathyroid hormone and hypophosphatemia increase the production of this form of the vitamin in the kidneys. Hypocalcemia acts in the same direction, but indirectly, affecting the level of parathyroid hormone. Hypercalcemia, hyperphosphatemia, and 1,25 (OH) 2D itself decrease the production of 1,25 (OH) 2D. The concentration of 1,25 (OH) 2D in normally growing children is higher than in adults, its level is increased in pregnant and lactating women.

What is the purpose of determining the level of 1,25-dihydroxyvitamin D3 in the blood

The 1,25 (OH) 2D study may be useful in assessing calcium metabolism in patients with kidney disease or hypercalcemia in addition to the 25 (OH) D determination. The test is not intended to screen for vitamin D deficiency or deficiency.

What May Affect the Test Result of 1,25-Dihydroxyvitamin D3 and Additional Uses

Study 1,25 (OH) 2D is inappropriate for screening purposes for general assessment of vitamin D status in the body.A normal level of 1,25 (OH) 2D does not exclude a deficiency of total vitamin D, most patients will have a normal level of this form due to its tight biochemical regulation (and sometimes even increased – as a result of a compensatory increase in the level of parathyroid hormone). However, this test can be useful in examining patients with chronic kidney disease. In these patients, with the progression of the disease, the kidneys’ ability to produce the active form of the vitamin, 1,25 (OH) 2D, decreases, although the level of 25 (OH) D in the blood may be within the reference range.Testing for 1,25 (OH) 2 D is useful for monitoring vitamin D therapy in these patients.

In addition, the test can be used to diagnose some congenital disorders of vitamin D metabolism. Vitamin D-dependent rickets type I is associated with 1-alpha-hydroxylase deficiency and is characterized by a decrease in the level of 1,25 (OH) 2D. For vitamin D-dependent rickets type II associated with a mutation of the vitamin D receptor gene, an increase in the concentration of 1.25 (OH) 2D is characteristic. In chronic granulomatous diseases and primary hyperparathyroidism, there is an increased conversion of 25 (OH) D to 1.25 (OH) 2D.The definition of 1,25 (OH) 2D is used in some clinical situations to distinguish primary hyperparathyroidism from other causes of hypercalcemia. The study can be used in the diagnosis of diseases associated with increased production of 1,25 (OH) 2D due to extrarenal activity of the enzyme 1-alpha-hydroxylase (sarcoidosis, tuberculosis, histoplasmosis, Wegener’s granulomatosis, Hodgkin’s disease, lymphoma).

90,000 Take a blood test for vitamin D (25 OH vitamin D, calciferol) at the KDL


General information.

Vitamin D is a substance necessary for life. A unique feature of vitamin D is that it is both a fat-soluble vitamin and a hormone-like substance. Vitamin D is usually ingested through food (eg, fish, fish oil supplements, dairy products, egg yolk) and is also produced in the skin when exposed to sunlight (ultraviolet light). According to the differences in the chemical structure, several variants of natural vitamin D are distinguished.D2 (ergocalciferol is a plant-derived vitamin) and D3 (cholecalciferol from animal products). Form D2 is commonly found in fortified foods and most drugs and supplements. Vitamin D3 is a form produced in the body and is also used in a number of dietary supplements. The “provitamins” D entered into the body are converted into a universal form: 25 – OH vitamin D. The 25-OH form of vitamin D is considered the main marker of the body’s saturation with vitamin D.This form is stable, circulates in the blood for a long time and reflects the pool of all metabolic variants of vitamin D transformations in the body.

The main role of vitamin D is to regulate the level of calcium, phosphorus and (to a lesser extent) magnesium. This vitamin is essential for the strength and health of bones, muscle tone. It has been proven that a normal level of cholecalciferol affects the growth and development of body tissues, is important for a full immune response, and reduces the risk of autoimmune diseases.

Vitamin D is considered an oncoprotector – a substance that prevents tumor transformation of cells.

Who usually lacks vitamin D:

90,045 90,046 seniors,

90,046 overweight patients,

  • for patients living in an area with few sunny days or wearing clothing that covers the whole body,
  • 90,046 patients using convenience foods or other monotonous meals.

    In what cases is the study usually prescribed?

    Test for total vitamin D (25-OH vitamin D) is prescribed for patients with signs of vitamin D deficiency.The study is advisable when observing patients with intestinal diseases, since vitamin D is fat-soluble and should normally be absorbed in the intestine with fats present in food.

    It is important to assess the level of vitamin D when obtaining altered values ​​of total calcium in the blood.

    Signs of a possible vitamin D deficiency can be: muscle weakness, pain in muscles and bones, paresthesia (“creepy feeling”) in the lips, tongue and fingers, increased tendency to fracture.

    For those who are interested in assessing the balance of different metabolic variants of substances of the vitamin D group, there are separate laboratory tests:

    What do the test results mean?

    Low blood levels of 25-hydroxyvitamin D may be associated with insufficient intake of vitamin D, or with a defect in intestinal absorption. Some drugs (for example, anticonvulsants and glucocorticoids) can negatively affect the metabolism of vitamin D in the body, and when these drugs are taken, the need for vitamin D increases.In patients with chronic kidney disease, synthesis of the active metabolite of vitamin D – 1.25 (OH) 2 D is usually reduced.

    High levels of 25-OH vitamin D usually reflect excess intake from food and supplements.

    Timing of the test.

    Usually results can be obtained within 1-2 days.

    How to prepare for the analysis?

    You can donate blood during the day, no earlier than 3 hours after a meal or in the morning on an empty stomach.You can drink clean water as usual. It is recommended to exclude vitamin preparations and dietary supplements containing vitamin D 3-4 days before donating blood.

    25-OH Vitamin D total (D2 / D3)

    25-OH Vitamin D is the main inactive form of the hormone contained in the blood, a precursor of the active hormone 1,25-dihydroxyvitamin D. Vitamin D is of two types by origin: endogenous (cholecalciferol), formed in the skin under the influence of sunlight, and exogenous ( ergocalciferol), which enters the body along with food (fatty fish, fish oil).In the liver, vitamin D is converted to 25-hydroxycalciferol, which is the main laboratory indicator for vitamin D levels in the body. In the blood, this form of the vitamin is transported in a complex with protein. In the kidneys, 25-OH-vitamin D is converted into a biologically active form of vitamin D – 1,25-dihydroxycalciferol (1,25-OH (2) -D), which stimulates the absorption of calcium in the intestine and the reabsorption of calcium and phosphorus in the kidneys. With vitamin D deficiency, the calcium level is compensated by its mobilization from the bone tissue, which leads to osteomalacia: rickets in children and osteoporosis in adults.

    Vitamin D deficiency is recognized as a serious medical problem worldwide. All residents of northern latitudes, incl. practically the entire territory of Russia, are in the zone of increased risk of vitamin D deficiency – this is due to dietary habits and lack of sunlight. Vitamin D is essential for the functioning of all major organs and tissues, and especially the reproductive system of men and women. Vitamin D is involved in calcium metabolism, ensuring the strength of the bones of the skeleton, in the regulation of carbohydrate and fat metabolism, resistance to infectious and inflammatory processes, is necessary for the synthesis of male and female sex hormones and the ability to conceive.In order to normalize the level of vitamin D in the body and correctly select the required dose, it is necessary to know the initial level in the body. Excessive vitamin D supplementation has negative consequences. Its excess is toxic and can cause nausea, vomiting, stunted growth and development, kidney damage, impaired calcium metabolism and the immune system. In this regard, it is important to control the level of vitamin D in the blood, timely diagnosis of its deficiency or excess.

    A study of the content of vitamin D in the blood is required:

    • To diagnose a deficiency or excess of vitamin D
    • To identify the causes of impaired calcium metabolism, bone pathology.
    • To monitor the effectiveness of treatment with vitamin D preparations

    90,000 what is the difference and which one to choose? Table for drugs and dietary supplements

    Vitamin D is understood as a group of chemically similar substances (vitamers) with a similar effect on the body. Most often, D2 (ergocalciferol) and D3 (cholecalciferol) can be found in drugs, since they have greater pharmacological efficacy than others.

    NB! There are vitamin D preparations based on its active metabolites calcitriol, alfacalcidol, and pro-vitamin D3 dihydrotachysterol (D4).These are prescription drugs and are used exclusively for therapeutic purposes (for active metabolites, the main indication is the treatment of osteoporosis, for dihydrotachysterol – hypocalcemia against the background of hypoparathyroidism). FBOs with calcium are also widely available on the market and will be the subject of one of the following articles.

    D2 (ergocalciferol) is formed from ergosterol in plant cells, yeast, some other fungi and fungi under the influence of UV rays.

    D3 (cholecalciferol) is naturally found in various animal products.It is he who is synthesized in our body under the influence of UV rays.

    Of these two forms, D3 is the more natural compound for our body and is better absorbed. D3 outperforms D2 in efficiency by 25%. The metabolism of ergocalciferol in the body takes longer and is accompanied by the formation of a number of by-products, which means that the risk of toxic effects in case of an overdose increases.

    The time of maintaining the concentration of the active metabolite of calcitriol in the blood in D2 is lower [1, 2, 3, 4].Vitamin D2 has a shorter shelf life than D3. Due to the low biological activity, vitamin D2 is practically not used and since 2012 has been excluded from the list of vital and essential medicines.

    At present, almost all medicines and dietary supplements contain vitamin D3.

    Oil / water? Capsules / tablets?

    Vitamin D is fat-soluble, therefore one of the simplest dosage forms is oil solution in liquid form or enclosed in capsules.Oily forms should be taken with food, they break down longer than water ones. The bioavailability of these forms will depend on the condition of the digestive system. They are not indicated for premature babies, as well as for persons with impaired function of the biliary system, because absorption of vitamin D depends on the formation and flow of bile into the intestines.

    Aqueous forms of vitamin D do not need to be broken down and are immediately absorbed in the intestine. They are micellar solutions. The fat-soluble part with vitamin D is located in the core of the particle, and the hydrophilic shell of the micelle allows them to be evenly distributed in the solvent.Aqueous vitamin D3 is absorbed 5 times faster than fat-soluble vitamin, reaches a higher concentration in the liver, where D3 is hydroxylated into its active form. lasts up to 3 months, in contrast to oil – up to 1.5-2 months [5]. The use of such forms is possible even with a lack of bile, as is the case in premature infants, and in people with pathologies in which the breakdown and absorption of fats is impaired.The disadvantages of water-soluble vitamin D preparations include the presence of excipients in the composition: preservatives, flavors and stabilizers. And although they are all present in acceptable norms, they can cause allergic reactions, especially in people who are prone to this.

    The disadvantages of all liquid forms are inaccurate dosing and inconvenience of use. In capsules – there can be an oily solution or dry powder of vitamin D dosed into gelatinous shells. All that has been said in terms of assimilation for oil solutions is also relevant for oil capsules.The advantage here is the dosage accuracy and greater ease of use.

    Tablets are distinguished by their dosing accuracy and ease of use. Contains dry crystalline vitamin D and excipients. Among them you can find chewable ones that do not need to be washed down with water and instant ones that are suitable for both adults and children.

    Sublingual spray is a new form of vitamin D. In terms of bioavailability, it surpasses all available forms, is absorbed from the oral cavity.While the sprays are presented in the form of imported dietary supplements.

    BAA or PP?

    On the pharmaceutical market, vitamin D is presented in a wide variety of forms, dosages, as well as in the form of dietary supplements and medicines.

    According to Russian legislation, the content of vitamin D in the form of dietary supplements should not exceed the daily requirement by more than 3 times for vitamin D (MUK In fact, the dosage ranges of vitamin D in dietary supplements and drugs overlap, below in the article you will find a link to the table on drugs and dietary supplements.

    Fundamental differences between drugs and dietary supplements in the general case are dosage accuracy, clinical trials, clear regulation of excipients, strict quality control. However, the situation on the market of dietary supplements and drugs is not so unambiguous, since many pharmaceutical companies first register it as a dietary supplement in order to bring a drug to the market. It is faster and cheaper [6]. There is also a reverse process, when a previously former medicinal product becomes a dietary supplement, since the mark-up for dietary supplements may be higher, and this is beneficial to the manufacturer.With all this, a dietary supplement is produced in accordance with the requirements for the production of medicinal products, and the quality of such a dietary supplement corresponds to the quality of the medicinal product. It also happens that a manufacturer does not want to register a dietary supplement as a drug, but to promote and increase confidence among potential consumers, it independently conducts clinical trials, which makes a note on the package and in the instructions. It is possible to recommend, when choosing in favor of dietary supplements, to pay attention to the reliability of the manufacturer, compliance with international GMP requirements, confirming the high quality and safety of products.

    We have prepared for you a convenient table of drugs and vitamin D supplements with trade names. Download here.

    The time for vitamin D deficiency is over. As a rule, now in the arsenal of a pharmacy there are a variety of proposals for vitamin D, from which you can always choose the best option in terms of release form, dosage, manufacturer and individual preferences.

    Interested in the article? You can find out more in the section Working in a pharmacy

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