About all

How does topiramate cause weight loss: Does Topiramate Speed Up Your Metabolism? – Simply Slim

Does Topiramate Speed Up Your Metabolism? – Simply Slim

Have you found that you could easily lose extra holiday weight in time for beach season when you were younger? Has your ability to lose weight ground to a halt or slowed to a glacial crawl? If so, you may be interested in learning more about topiramate, a weight-loss tool proudly offered at Simply Slim Medical in Bethesda, MD. Keep reading to discover whether this prescription medication speeds up your metabolism, how quickly it works, and more.

Does Topiramate Speed Up Your Metabolism?

Yes, topiramate speeds up your metabolism. This means that your body will burn more calories than usual, even when you are sedentary. If you manage your diet appropriately, you can lose weight on this drug very quickly without spending hours per week in the gym. If you choose to exercise, you will find it far more effective for calorie burning than it was before you went on the medication. Here are some other ways this drug facilitates weight loss.

Appetite Suppression

This drug is also known to facilitate weight loss by suppressing appetite. In other words, it will help you stick to your diet because you won’t feel as hungry as you usually do. Nonetheless, you still have to make a conscious effort to make good decisions. You may find that you don’t have the appetite to eat a double bacon cheeseburger and a large order of french fries for dinner. However, it is still possible to consume too many calories by drinking.

While this drug will boost your metabolism, you need to make sure that you are only drinking alcohol in moderation and accounting for your calories from alcohol in your daily caloric budget. This is especially true if you are not drinking straight liquor because wine, beer, and non-alcoholic beverages added to cocktails are usually high in carbohydrates.

An Additional Word on Beverages

It is advisable to stop drinking soda due to the incredible sugar content in soda. You can drink diet soda and lose weight, but drinking black coffee, unsweetened tea, and water will be better for your health than drinking soda with sugar substitutes and other chemicals. Also, if you want to drink juice, it is highly advisable to juice your own fruits at home. Most juice you can buy from the grocery store is highly processed and less healthy than homemade juice.

Finally, if you find yourself craving a smoothie, you should make your own smoothie if you can. If you make it at home, you can make it with frozen fruits and veggies in addition to fresh produce, so you don’t need to ensure you have enough ice ahead of time. If you get a smoothie at a smoothie bar, ask for it with Greek yogurt or coconut water instead of ice cream.

Addiction Control

Topiramate also facilitates weight loss by reducing the excitation of the nerves in your brain’s addiction centers. If you’re like many Americans, you are addicted to sugar. If you try to cut back on your sugar consumption to lose weight, you may experience such withdrawal symptoms as dizziness, fatigue, debilitating headaches, difficulty concentrating, cravings, depression, and anxiety.

This drug changes the neural pathways in these parts of the brain, reducing withdrawal symptoms, including cravings and mood swings. Therefore, you will be less likely to binge due to anxiety or depression caused by sugar withdrawal.

Altered Hormone Levels

You will find weight loss easier if you take topiramate because it reduces the amount of leptin your body produces. Leptin is known as the hunger hormone and tells you that you need to fuel your body. This drug also reduces cortisol, a hormone known to cause belly fat gain.

How Quickly Can I Lose Weight With This Drug?

You can expect to lose weight quickly if you take this drug, but it may be between one and four months before you really start to see the fat loss in yourself. How fast you lose weight depends on numerous factors, including the dose you take, how much you exercise, how hydrated you remain, and how many calories you eat. The type of calories you choose to eat will also affect how quickly you lose weight.

Am I a Good Candidate for Weight Loss With This Tool?

You can expect to qualify for weight loss with this pharmaceutical if your goal is to lose a lot of weight quickly. However, to find out definitively whether you qualify for this treatment, you will need to attend an initial evaluation. We need to evaluate your current health, discuss your past health, and talk about the drugs and supplements you are currently taking.

The Bottom Line

The bottom line is that Topamax boosts your metabolism. It also helps to facilitate weight loss by suppressing appetite, inducing ketosis, controlling addiction, and affecting your hormone levels. If your goal is to lose a lot of weight quickly, you may be a good fit for this treatment. To find out for sure, drop us a line at Simply Slim Medical in Bethesda, MD if you are in the DMV area. We proudly serve Tysons Corner, VA, Falls Church, VA, and D.C. residents.

Topamax for Weight Loss: Uses, Dosage, Side Effects

  1. Does Topamax work for losing weight?
  2. What is Topamax?
  3. Topamax uses
  4. Topamax side effects
  5. Topamax dosage
  6. Topamax warnings
  7. Topamax interactions 

It may sound strange, but one of the drugs most commonly prescribed for weight loss is not FDA-approved for that purpose. It’s a seizure medication called Topamax (topiramate), that happens to come with a welcome side effect for many people: weight loss. Studies have shown that Topamax can help you lose weight by reducing appetite, so many healthcare providers prescribe it off-label for that purpose. It’s not a magic pill, though. This drug can have several side effects, some of them serious. Find out more below.

Studies have found that about 6–17% of people who take Topamax will lose body weight (National Library, 2021). One review of studies found that people with obesity who took Topamax for at least four months lost an average of about 12 pounds more than the placebo group (Kramer, 2011).

Topamax (topiramate) is FDA-approved to treat seizure disorders (like epilepsy) and migraines. Because one of the side effects is decreasing appetite, some providers prescribe Topamax off-label as a weight loss medication. Other common brand names for this drug are: Qudexy XR, Topiragen, and Trokendi XR. 

Topamax is approved by the FDA for the treatment of (National Library, 2021; FDA, 2012): 

  • Epilepsy, a neurological disorder in which brain activity becomes abnormal, causing seizures or other types of unusual behavior
  • Migraine headaches, which are recurrent, throbbing headaches that typically affect one side of the head

Topamax can also be used “off-label” to treat other conditions, meaning it wasn’t specifically approved by the FDA for those uses. Drugs can be prescribed by a healthcare provider for an unapproved use if they decide that it’s the right treatment for their patient. 

Off-label uses for Topamax include:

  • Weight loss
  • Alcohol dependence (MedlinePlus, 2021)

Weight loss plateau: why it happens and 7 ways to get past it

Weight management

Last updated: Oct 25, 2021

6 min read

Common side effects of Topamax include (Fariba, 2021; National Library, 2021):

  • Paresthesia (tingling or prickling sensations)
  • Altered sense of taste

Topamax can have serious side effects:

  • Myopia (nearsightedness) and glaucoma
  • Vision defects
  • Metabolic acidosis
  • High blood ammonia levels
  • Trouble with thinking or concentration
  • Nausea
  • Confusion
  • Memory problems
  • Trouble speaking
  • Depression or mood problems
  • Suicidal tendencies
  • Tiredness or sleepiness
  • Serious skin reactions, including rash or blisters
  • Kidney stones
  • Low body temperature
  • Hair loss

Topamax comes in the following forms (National Library, 2021; Medline Plus, 2021):

  • Tablets: 25 mg, 50 mg, 100 mg, and 200 mg
  • Sprinkle capsules: 15 mg and 25 mg

Because Topamax hasn’t been approved by the FDA for weight loss, no specific dosage is recommended for that use. Your healthcare provider will recommend a dose based on your health history, physical condition, and other factors.

  • Pregnant women shouldn’t take Topamax because it can increase the risk of congenital anomalies (especially cleft lip and cleft palate) in the infant.
  • Acute myopia and glaucoma—rare but possible side effects of Topamax—can lead to permanent vision loss.  
  • Metabolic acidosis, in which too much acid is produced in the body, can lead to shock or death when severe.
  • Antiepileptic drugs, including Topamax, can increase suicidal thoughts or behavior.

Weight loss motivation: 5 tips for keeping up your momentum

Weight management

Last updated: Sep 02, 2021

6 min read

Topamax can interact with the following drugs (National Library, 2021):

  • Antiepileptic drugs—Taking phenytoin and carbamazepine with Topamax can decrease blood levels of Topamax. Taking valproic acid with Topamax may cause low body temperature and high levels of ammonia.
  • Carbonic anhydrase inhibitors—Topamax is a carbonic anhydrase inhibitor. Taking it with other such medications (like zonisamide and acetazolamide) can increase the risk of metabolic acidosis and kidney stones.
  • Central nervous system (CNS) depressants—Topamax alone may cause CNS depression, so it should be used with extreme caution with other CNS depressants, like alcohol.
  • Combination oral contraceptives (birth control pills)—Topamax may cause combination oral contraceptives to be less effective.
  • Hydrochlorothiazide (HCTZ)—HCTZ is a diuretic (water pill). Taking it together with Topamax can cause concentrations of Topamax to rise, which could be dangerous.
  • Lithium—Lithium is used to treat bipolar disorder and other mental illnesses. Taking it together with Topamax can increase the blood levels and effects of lithium.
  • Amitriptyline—Amitriptyline is used to combat depression. Taking it together with Topamax can cause a large increase in the concentration of amitriptyline.

If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

  1. Fariba, K. & Saadabadi, A. (2021). Topiramate. [Updated 2021 Aug 6]. In: StatPearls [Internet]. Retrieved on Nov. 3, 2021 from https://www.ncbi.nlm.nih.gov/books/NBK554530/
  2. Food and Drug Administration. (2012). Topamax (topiramate) Prescribing Information. Retrieved from https://www.accessdata.fda.gov/drugsatfda_docs/label/2012/020844s041lbl.pdf
  3. Kramer, C. K., Leitão, C. B., Pinto, L. C., Canani, L. H., Azevedo, M. J., & Gross, J. L. (2011). Efficacy and safety of topiramate on weight loss: A meta-analysis of randomized controlled trials. Obesity Reviews: An Official Journal of the International Association for the Study of Obesity, 12(5), e338–e347. doi: 10.1111/j.1467-789X.2010.00846.x. Retrieved from https://pubmed.ncbi.nlm.nih.gov/21438989/
  4. Medline Plus. (2021). Topiramate. U.S. National Library of Medicine. Retrieved from https://medlineplus.gov/druginfo/meds/a697012.html
  5. National Institutes of Health. (2021). TOPAMAX- topiramate capsule, coated pellets. Retrieved from https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=21628112-0c47-11df-95b3-498d55d89593
  6. U.S. National Library of Medicine. (2021). DailyMed. Label: TOPAMAX- topiramate tablet, coated. TOPAMAX- topiramate capsule, coated pellets. National Institutes of Health. Retrieved from https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=21628112-0c47-11df-95b3-498d55d89593

Dr. Steve Silvestro is a board-certified pediatrician and Senior Manager, Medical Content & Education at Ro.

Phentermine + Topiramate – instructions for use

Phentermine + Topiramate


  • Pharmacological action
  • Readings
  • Contraindications
  • With care
  • Pregnancy and breastfeeding
  • Side effects
  • Interaction
  • Special instructions
  • Transport management
  • Sports medicine
  • Classification

Pharmacological action

The drug is a combination of phentermine and topiramate used to treat obesity.

Phentermine is a sympathomimetic amine, causes an anorectic effect due to the release of norepinephrine in the hypothalamus, causing appetite suppression due to an increase in the concentration of leptin in the blood, the exact mechanism of action is not fully understood.

Topiramate – the effect can be manifested in the form of suppression of appetite and increased satiety, which is caused by a combination of pharmacological effects: increases the activity of γ-aminobutyric acid (GABA) against certain subtypes of GABA receptors (including GABA A receptors), and also modulates the activity of the GABA A receptors themselves, prevents the activation of kainate sensitivity of the kainate / AMPK subtype (α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid) glutamate receptors, does not affect the activity of N-methyl-D-aspartate (NMDA) in relation to the NMDA receptor subtype.


Weight management (in addition to low calorie diet and exercise).


  • Known hypersensitivity or individual intolerance to sympathomimetic amines;
  • Concomitant use of monoamine oxidase (MAO) inhibitors or within the last 14 days;
  • Glaucoma;
  • Hyperthyroidism;
  • Pregnancy.


The effect of the drug on cardiovascular morbidity and mortality has not been established.

The safety and efficacy of Phentermine + Topiramate in combination with other weight loss drugs, including prescription and over-the-counter drugs and herbal preparations, have not been established.

Pregnancy and lactation

Use in pregnancy

FDA fetal category X.

Women of reproductive age and men who are sexually active should use reliable methods of contraception during treatment. A negative pregnancy test should be obtained prior to starting treatment and should be performed monthly in women of childbearing potential.

Data from pregnancy registries and epidemiological studies indicate a 5-fold increased risk of oral clefts (cleft lip with or without cleft palate) with topiramate exposure in the first trimester. Animal studies with clinically relevant doses of topiramate have revealed embryofetal toxicity, including craniofacial defects; increased mortality; weight loss and ossification of the skeleton; delayed physical development; malformations of the limbs, ribs and vertebrae. Evidence of maternal toxicity, such as reduced weight gain and mortality, has also been observed in animal studies with topiramate. Studies on the degree of influence of phentermine on pregnancy have not been conducted.

Combination treatment with phentermine and topiramate in animals at doses approximately 5 to 6 times the maximum recommended human dose caused toxicity in offspring and significantly reduced maternal weight gain. Offspring effects included lower survival after birth; an increase in malformations of the limbs and tail; weight loss; delayed growth, development and puberty without compromising learning, memory, fertility and reproduction.

The drug may cause metabolic acidosis. Metabolic acidosis during pregnancy can lead to decreased fetal growth, reduced fetal oxygenation, fetal death, and may affect the ability of the fetus to endure labor.

In the event of pregnancy, absence of menstruation or suspected possible pregnancy, the patient should inform her physician. If the partner of a patient taking the Phentermine + Topiramate combination becomes pregnant, the physician should be informed of possible adverse effects to the fetus. If this drug is used during pregnancy or pregnancy occurs while taking the drug, treatment should be stopped immediately.

Use during breastfeeding

The drug may be present in breast milk because topiramate and amphetamines are excreted in breast milk. Phentermine has pharmacological activity and chemical structure similar to amphetamines.

Either stop taking the drug or stop breastfeeding, taking into account the importance of the drug to the mother.

Side effects

The most common adverse reactions (occurring ≥5% and ≥1.5 times more than placebo) include: paresthesia, dizziness, dysgeusia, insomnia, constipation, and dry mouth.



Phentermine may reduce the effect of drugs such as clonidine, methyldopa and guanethidine.

Drugs for the treatment of hypothyroidism may increase the effect of phentermine.


When used simultaneously with topiramate, phenytoin and carbamazepine reduce its plasma concentration. This is due to the induction under the influence of phenytoin and carbamazepine of enzymes, with the participation of which the metabolism of topiramate is carried out. In some cases, when using topiramate, an increase in the concentration of phenytoin in the blood plasma was observed.

Co-administration of a single dose of topiramate and digoxin may reduce the AUC of digoxin.

With the simultaneous use of an oral contraceptive containing norethindrone and ethinylestradiol, topiramate did not significantly affect the clearance of norethindrone, however, the plasma clearance of ethinylestradiol increased significantly. Thus, while taking topiramate with oral contraceptives, their effectiveness may be reduced.

In patients taking metformin, pioglitazone, glibenclamide, fluctuations in plasma glucose levels are possible with the simultaneous use or withdrawal of topiramate. With these combinations, plasma glucose levels should be monitored.

Concomitant use of topiramate with drugs that predispose to the development of nephrolithiasis may increase the risk of kidney stones.

Special instructions

The drug may harm the fetus.

The drug may cause an increase in resting heart rate up to 20 beats per minute, dose adjustment or discontinuation is necessary if there is a steady increase in resting heart rate. Use caution when prescribing to patients with a history of cardiac or cerebrovascular disease

Antiepileptic drugs, including topiramate, increase the risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Patients taking the Phentermine + Topiramate combination should be monitored for the onset or worsening of depression, suicidal thoughts or behavior, and/or any unusual changes in mood or behavior. It is necessary to stop taking the drug in patients who experience suicidal thoughts or behavior.

Acute myopia associated with secondary angle-closure glaucoma has been reported with topiramate. IOP monitoring is necessary because of the risk of irreversible vision loss. Discontinue therapy in patients with ocular pain or acute onset of decreased visual acuity

May cause mood disorders including depression and anxiety, as well as insomnia, patients with a history of depression may be at increased risk of recurrent depression or other mood disorders. Most of these mood and sleep disorders resolved spontaneously or disappeared after discontinuation of the drug.

There are reports of cognitive dysfunction (eg, impaired concentration/attention, memory problems, and problems with speech or language, especially difficulty finding words). Rapid titration or high initial doses may be associated with these cognitive phenomena. Since the drug has the potential to impair cognitive function, patients should be warned not to work with machines that require increased concentration, including cars, until they are sufficiently confident that the therapy does not adversely affect them. If cognitive dysfunction persists, dose reduction or drug withdrawal should be considered.

Hyperchloraemic, non-anion gap and metabolic acidosis have been reported. It is recommended to monitor the level of electrolytes and bicarbonate in the blood serum before and during treatment. Reduce the dose of the drug or discontinue use if persistent metabolic acidosis develops.

May cause an increase in serum creatinine, reflecting a decrease in kidney function (glomerular filtration rate). In phase 3 studies, peak increases in serum creatinine were observed after 4–8 weeks of treatment.

Weight loss may increase the risk of hypoglycemia in type 2 diabetic patients receiving insulin and/or insulin secretagogues. It is recommended to monitor the need to adjust diabetic therapy.

In patients treated for hypertension, weight loss may increase the risk of hypotension. It is recommended to monitor the need to adjust the dose of antihypertensive drugs.

Co-administration with ethanol or CNS depressants, phentermine or topiramate may increase CNS depression or other centrally mediated effects of these agents (eg, dizziness, cognitive adverse reactions, drowsiness, dizziness, incoordination, drowsiness).

Antiepileptic drugs, including topiramate, should be discontinued gradually to minimize the possibility of increased seizure frequency.

Use caution in renal or hepatic impairment.

Some patients, especially those with a predisposition to nephrolithiasis, may have an increased risk of kidney stones and associated symptoms such as renal colic, kidney pain, flank pain. To reduce this risk, an adequate increase in fluid intake is necessary. Risk factors for the development of nephrolithiasis are a history of nephrolithiasis (including family history), hypercalciuria, concomitant therapy with drugs that contribute to the development of nephrolithiasis.

Oligohidrosis (leading to hyperthermia) has been reported with topiramate, and caution and monitoring is advised in patients receiving carbonic anhydrase inhibitors and anticholinergic drugs, or during exposure to high ambient temperatures or exercise.

May cause altered laboratory values, may increase risk of hypokalemia due to inhibition of carbonic anhydrase activity, caution when used concomitantly with drugs that cause hypokalemia (eg, furosemide, hydrochlorothiazide)

Monitoring of blood chemistry at the start and during therapy is recommended.

Use with combined oral contraceptives may increase the incidence of irregular bleeding/spotting, therapy should not be discontinued if bleeding does not bother the patient

Consider dose reduction in patients with hepatic impairment, use with caution.

Phentermine, an ingredient in the drug, is potentially dangerous for abuse.

Phentermine is included in Schedule II of the list of narcotic drugs, psychotropic substances and their precursors subject to control in the Russian Federation.

Influence on the ability to drive vehicles and control mechanisms

It is necessary to refrain from driving vehicles and engaging in activities that require increased concentration of attention and speed of psychomotor reactions.

Sports medicine

Phentermine may cause anti-doping rule violations and positive results in doping controls.

Phentermine belongs to class S6 Stimulants on the WADA Prohibited List.

⚠ Prohibited substances should not be used to enhance athletic performance as they pose a serious health risk.


Term Description
WADA World Anti-Doping Agency


  • ATX


  • Pharmacological groups

    Appetite regulators, combinations

    Antiepileptic drugs in combination with other drugs

  • FDA pregnancy category


Share this page

More on the topic

Read more about the active substance Phentermine + Topiramate:

  • Reviews
  • Questions
  • Latin name
  • Chemical formula

Information about the active substance Phentermine + Topiramate is intended for medical and pharmaceutical professionals, for reference purposes only. The instructions are not intended to replace professional medical advice, diagnosis or treatment. The information contained here may change over time. The most accurate information on the use of preparations containing the active substance Phentermine + Topiramate is contained in the manufacturer’s instructions attached to the package.

Benefits, Side Effects and Dosage

A properly balanced, low calorie diet and regular exercise are the cornerstones of weight loss, but some drugs can be powerful supporters.

One such drug is phentermine, one of the world’s most popular weight loss drugs.

It has been shown to be effective for short term weight loss when used along with a reduced calorie diet and exercise.

However, the use of phentermine for weight loss is not without risks and side effects.

This article explains everything you need to know about phentermine, including its benefits, dosage, and possible side effects.

  • What is it
  • How does it work?
  • What is it used for?
  • Dosages and forms
  • Side effects and precautions
  • Healthy weight loss

What is phentermine?

Phentermine is a prescription drug for weight loss.

The Food and Drug Administration (FDA) approved it in 1959 for short-term use up to 12 weeks for people over 16 years of age.

In the 1990s, drug manufacturers combined phentermine with other weight loss drugs. This combination of drugs has received the general name fen-fen.

Following reports of significant heart problems among users, the FDA withdrew two other drugs used in treatment, fenfluramine and dexfenfluramine, from the market.

Today, phentermine can be used alone and is marketed under the trade names Adipex-P, Lomaira and Suprenza. You can also find it in combination weight loss medications like Qsymia, which combines phentermine and another drug called topiramate.

Phentermine is a stimulant and is available by prescription. Since taking phentermine comes with a risk of addiction, it is considered a controlled substance. Chemically, it is similar to the stimulant amphetamine, which is also a controlled substance.

Your healthcare provider may prescribe phentermine if you are obese, as defined by a body mass index (BMI) of 30 or higher.

Health care providers may also prescribe it if you are overweight with a BMI greater than or equal to 27 and have at least one weight-related condition such as high blood pressure, high cholesterol, or type 2 diabetes.

We offer you:
Black Seed Oil: Benefits, Dosages and Side Effects

However, a healthcare professional will likely recommend other weight loss strategies first, such as exercise and a reduced calorie diet.

General Information: Phentermine is an FDA approved weight loss drug. Its chemical structure is similar to that of the stimulant amphetamine, and it is only available by prescription.

How does phentermine work?

Phentermine belongs to a class of drugs called anorectics, also known as appetite suppressants.

Taking phentermine helps suppress your appetite, thereby limiting the amount of calories you consume. Over time, this can lead to weight loss.

Although the exact way phentermine reduces appetite remains unclear, it is believed that the drug works by increasing the levels of neurotransmitters in your brain.

Neurotransmitters – the chemicals norepinephrine, serotonin and dopamine – are your body’s chemical messengers.

As your levels of these three chemicals rise, your hunger will decrease.

However, within a few weeks you may develop a tolerance to the appetite-suppressing effects of phentermine. If this happens, talk to the healthcare professional who prescribed it.

Trivia: Phentermine is said to reduce appetite by increasing neurotransmitter levels in your brain.

What is phentermine used for?

Phentermine is most commonly used for weight loss, but may also be used in combination with the drug topiramate to help with certain eating disorders such as binge eating disorder (BED).

We offer you: 9 benefits of vitamin B6 (pyridoxine)

Phentermine is effective for weight loss

Several clinical studies have shown that phentermine can support meaningful weight loss.

Although the FDA has only approved it for short-term use of less than 12 weeks, off-label phentermine is often prescribed by healthcare professionals for longer use.

Doctors may prescribe it intermittently, meaning you take a break from taking the medicine for a certain period before you start taking it again.

Average weight loss with phentermine is 3% of your initial body weight after 3 months and 5-7% after 6 months. Some people report even greater weight loss than this.

To put this in perspective, a 5-7% weight loss is 10-14 pounds (4. 5-6.4 kg) for a person who weighs 200 pounds (90.7 kg).

However, not everyone reacts to this medicine in the same way. If you haven’t lost much weight after 3 months of using it, your healthcare professional may recommend that you stop taking the drug.

Further, its effectiveness seems to decrease gradually after more than a year of continuous use.

While phentermine is effective for weight loss, it may work better when combined with topiramate.

Topiramate is a drug that has been used on its own to treat seizures but, like phentermine, also has appetite-reducing properties.

Topiramate and phentermine is a combination drug sold under the brand name Qsymia. The FDA approved it in 2012 as a supplement to a healthy lifestyle such as increased exercise and a reduced calorie diet.

Compared to three other commonly prescribed weight loss drugs, the combination of phentermine and topiramate was associated with the highest chance of losing at least 5% of initial body weight.

What’s more, a recent analysis of studies found that people who took the combination drug phentermine and topiramate lost an average of 16 pounds (7.3 kg) compared to placebo.

Here’s to you: Inositol: Benefits, Side Effects, and Dosage

For those who have taken the drug for more than 56 weeks, this number has increased to 17.8 pounds (8 kg).

In addition, the degree of weight loss increased with increasing dose. Mean weight loss was:

  • 7.8 lbs (3.55 kg) for the 3.75/23 mg dose (Phentermine/Topiramate)
  • 16 lbs (7.27 kg) for the 7.5/46 mg dose
  • 18 lbs (8.25 kg) for 15/92 mg dose

In phentermine-topiramate users, weight loss resulted in a significant reduction in waist circumference, as well as improved insulin sensitivity, improved blood sugar management, and decreased blood pressure .

Phentermine may be useful for some eating disorders

The combination of phentermine and topiramate may help reduce overeating in people with BED and bulimia nervosa.

BED is characterized by eating large amounts of food, often quickly and to the point of discomfort. It is also associated with feelings of loss of control during overeating, as well as feelings of shame or guilt afterwards.

Bulimia nervosa includes the same binge eating behaviors as BED, but also includes behaviors people use to compensate for the effects of binge eating, such as self-induced vomiting.

In a small 12-week study in overweight people with BED, people who took the combination of phentermine and topiramate experienced a significant reduction in the frequency of binge eating episodes.

In another 12-week study, people with BED or bulimia nervosa received a combination of drugs or a placebo.

In 28 days, treatment with the combination of phentermine and topiramate reduced participants’ binge days from 16.2 to 4.2. The same results were not observed in the placebo group.

Although these results are promising, larger studies are still needed.

If you think you have BED, bulimia nervosa, or an eating disorder, it’s important to talk to a healthcare professional.

General Information: Phentermine in combination with topiramate has been shown to promote significant weight loss and may help reduce the frequency of binge eating episodes.

Phentermine dosage and formulation

Phentermine dosages vary depending on its form and concentration.

We offer you:
L-Carnitine: Benefits, Side Effects, Sources and Dosage


Until 2016, the only available doses of phentermine were 15, 30, and 37.5 mg.

However, since best practice for clinicians is to prescribe the lowest effective dose, the FDA approved an 8-mg formula (Lomaira) in 2016 that can be taken up to three times daily, at least 30 minutes before meals.

If you are prescribed a higher dose (15, 30 or 37.5 mg), you can take it once a day in the morning before breakfast or 1-2 hours after breakfast.

To prevent insomnia or difficulty falling or staying asleep, you should avoid taking your last dose too late in the day.

Phentermine and Topiramate

The combination of phentermine and topiramate – sold under the brand name Qsymia – is a medicine used for weight loss.

This medicine is available in four doses ranging in strength from phentermine 3.75-15 mg and topiramate 23-92 mg. It is offered in extended release capsules to be taken in the morning.

After you have taken the lowest dose for 14 days, your doctor may decide to change you to a higher dose.

According to the FDA, you should stop using the medication if you do not lose 3% of your body weight after 12 weeks of the highest daily dose.

General Information: The dosage of phentermine varies depending on whether it is used alone or with topiramate.

Phentermine side effects and precautions

Phentermine itself is for short-term use only, as there are few long-term studies on its safety.

One study noted that people did not experience significant side effects when they took phentermine for up to 24 months.

However, the FDA approved phentermine in combination with topiramate for long-term use because the doses of the two ingredients are lower than the maximum doses of the individual drugs.

The most commonly reported side effects of phentermine and combined phentermine and topiramate are:

  • dry mouth
  • sleep problems
  • dizziness
  • palpitations
  • flushing of the skin
  • fatigue
  • Constipation
  • irritability
  • nausea
  • vomiting

Although rare, some serious side effects may occur such as increased blood pressure, suicidal ideation, metabolic acidosis, increased creatinine levels, harm to the fetus, vision problems, cognitive impairment, and hypokalemia.

Here are 15 helpful tips for overeating

You should not take phentermine if you have heart disease, hyperthyroidism, glaucoma, severe kidney or liver disease, or if you are pregnant or breastfeeding.

Phentermine should also not be given in combination with monoamine oxidase inhibitors (MAOIs), a class of drugs used to treat depression.

Talk to a healthcare professional if you are taking other medicines, such as antihypertensives or antiepileptics.

Your healthcare professional will determine if phentermine is right for you and if it is safe for you.

General Information: Although some common side effects are associated with the use of phentermine and topiramate, most people tolerate them. However, people who have certain medical conditions or who are pregnant or breastfeeding should not use phentermine and topiramate.

Healthy Ways to Promote and Maintain Weight Loss

Phentermine and topiramate are most commonly prescribed by healthcare professionals after you have tried other weight loss lifestyle modifications without seeing significant results.

While phentermine can be a powerful weight loss aid, the only proven way to lose weight and keep it off in the long run is through a healthy lifestyle.

Without these habit changes, you may be able to regain all of the weight you lost – and possibly more – after you stop taking phentermine.

Instead, opt for healthy, sustainable lifestyle habits that promote health beyond weight loss.

Extensive research has shown that exercise, nutrition, stress management and proper sleep are critical to promoting health and reducing the risk of disease.

What’s more, long-term medication is not without risk, and costs can increase, especially if you don’t have insurance.

For these reasons, your healthcare provider will likely recommend you make healthy lifestyle changes before recommending a weight loss drug.

Here’s How to Lower Your Insulin Levels

Some examples of healthy lifestyle changes you can make include:

  • Reduced calorie eating. If you need to lose weight, you can try eating 300-500 fewer calories a day. A registered dietitian can help you find this range based on your preferences and goals.
  • Give priority to foods rich in nutrients. Nutrient-rich foods such as fruits and vegetables are relatively low in calories and high in nutrients such as fiber, vitamins and minerals.
  • Increased physical activity. The US Department of Health and Human Services recommends getting at least 150 minutes per week of moderate aerobic exercise, such as brisk walking or running.
  • Get more sleep. Although individual needs vary, try to get 7-9 hours of sleep per night.
  • Do your best to manage your stress levels. Stress management may help reduce emotional eating and inflammation. You can try strategies such as taking medication, walking, talking to friends and family, or talking to a qualified professional.
  • Try behavioral strategies. Behavioral changes that may be helpful include self-monitoring of food intake, physical activity, and weight, and making adjustments as needed.

These lifestyle changes can be difficult and you don’t have to do everything at once. Instead, slowly introduce new healthy behaviors over time. This will contribute to long-term, sustainable results.

General Information: Lifestyle and behavior modifications are the cornerstones of successful weight loss and maintenance.


Phentermine is a prescription-only appetite suppressant and diet pill approved for short-term use.

The combination of phentermine and topiramate is even more effective than phentermine alone and is approved for long-term use. It may also help reduce drinking episodes in people with BED.

We offer you:
Can thermogenic supplements help you burn fat?

Common side effects include dry mouth, dizziness, fatigue, irritability, and constipation. You should not use this medicine if you have heart disease, hyperthyroidism, glaucoma, severe kidney or liver disease, or if you are pregnant or breastfeeding.