Key takeaways:
Topamax (topiramate) is a medication that’s FDA approved for seizures and to prevent migraines. But it’s also prescribed off-label for weight loss. It’s also combined with phentermine in an FDA-approved weight-loss medication called Qsymia.
Studies show that on average, people taking Topamax for weight loss lose around 5% to 7% of their body weight after 24 weeks of treatment. Higher doses and longer duration of use generally result in more weight loss.
The most common Topamax side effects are abnormal skin sensations (like burning, tingling, numbness), altered sense of taste, and slowed thinking and movements. Talk to your prescriber to determine if Topamax is an appropriate medication for your needs.
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Topamax (topiramate) is an antiepileptic (anti-seizure) medication. It’s FDA approved to treat seizure disorders and prevent migraines. But it’s also prescribed off label for weight loss. This means Topamax may help you lose weight, but it isn’t FDA-approved for this use.
Let’s take a look at how Topamax works for weight loss, along with tips for taking it and ways to minimize side effects.
How does Topamax work for weight loss?
It’s unknown exactly how Topamax works for weight loss. But it seems to:
Reduce appetite and help you feel full sooner
Lower triglyceride and cholesterol levels
Increase metabolism
Make food feel less rewarding
Reduce levels of a hormone called leptin, which in turn reduces fat storage in the body
Topamax may also help manage weight gain and changes in blood glucose (sugar) caused by antipsychotic medications, such as olanzapine (Zyprexa). But evidence for this is mixed.
How effective is Topamax for weight loss?
Topamax seems to be effective for weight loss. Studies show that people taking Topamax typically lose around 5% to 7% of their starting body weight after 24 weeks (6 months) of treatment. More weight loss was reported with longer treatment and higher doses of Topamax.
Qsymia is an FDA-approved weight-loss medication that combines Topamax and phentermine (Adipex-P, Lomaira). It seems to work better than other prescription weight-loss pills. But neither Topamax nor Qsymia typically result in as much weight loss as GLP-1 medications, such as Wegovy (semaglutide) and Zepbound (tirzepatide).
What’s the best Topamax dosage for weight loss?
Since it isn’t approved for weight loss, there isn’t a set Topamax dosage for this use. In studies, effective doses of Topamax for weight loss range from 64 mg to 400 mg per day. Doses on the higher end of this range may result in more weight loss, but they’re also associated with more side effects.
As for Qsymia, the recommended starting dosage is 3.75 mg/23 mg (phentermine / topiramate ER) by mouth once daily for 14 days. It’s then raised to 7.5 mg/46 mg by mouth once daily. After 12 weeks (3 months), your prescriber may increase your dose further based on how you’re responding to the medication.
The best dose of Topamax for weight loss will vary from person to person. You can work with your prescriber to find a dosage that’s safe and effective for you.
How long will it take to lose weight with Topamax?
In studies, people observed noticeable weight loss as soon as 1 month (4 weeks) after starting Topamax. But it may take longer in some cases. People who take Qsymia typically see results in the first 8 weeks of treatment.
Studies show that the longer you take Topamax, the more weight you typically lose. As mentioned, higher doses seem to result in more weight loss but may cause more side effects. Keep in mind that slow, steady weight loss is safer and more sustainable long-term.
Other oral weight-loss medications may stop working as well after about 6 months. But this doesn’t seem to be the case with Topamax. Weight loss seems to continue even after 1 year of treatment, especially in those whose body mass index (BMI) is 30 or greater.
What should you do if you’re not losing weight while taking Topamax?
If you’re taking Topamax and you’re not losing weight, there are several things to consider:
Give it time. It’s possible that you haven’t waited long enough for Topamax to work. It’s best to wait at least 4 weeks before deciding that it isn’t working for you.
Be sure to incorporate lifestyle changes. You can help Topamax work better by adding a regular exercise routine and eating a nutritious diet. Talk to your healthcare team if you need tips for making sustainable changes.
Change your dosage (with your prescriber’s OK). Talk to your prescriber to see if a higher dose of Topamax is an option for you.
Try a different medication. If Topamax doesn’t work for you, talk to your prescriber about other weight-loss medications. It may take some trial and error to find the option that works best for your body chemistry.
What’s the best time to take Topamax for weight loss?
You’ll typically take Topamax once or twice daily for its approved health conditions. Since there isn’t an approved dosage for weight loss, your prescriber will determine the best dose and frequency for you. Food doesn’t affect how well Topamax works, so you can take it with or without a meal.
It’s recommended to take Qsymia once daily in the morning. The phentermine component of Qsymia is a stimulant and can make it hard for you to fall asleep. So you should avoid taking it in the evening.
Are there side effects of Topamax to be aware of?
Common Topamax side effects include abnormal skin sensations (such as burning, tingling, or numbness), altered sense of taste, and slowed thinking and movements. These may improve as your body adjusts to the medication.
Other notable side effects include:
Memory and concentration problems
Feeling nervous
Mood changes
Dry mouth
Changes in vision
Fatigue
Studies show that Topamax doses over 96 mg per day are usually associated with more side effects. It’s best to use the lowest effective dose to avoid unwanted side effects from this medication. If any side effects are bothersome, talk to your healthcare team for guidance.
Who shouldn’t take Topamax for weight loss?
There are risks associated with any medication, and Topamax is no exception. Topamax can cause or worsen the following conditions:
Suicidal thoughts or behaviors
Osteoporosis (weak or brittle bones)
Liver or kidney problems
History of metabolic acidosis (excess acid in the blood)
Glaucoma
Topamax may also cause harm to a fetus. If you’re pregnant, you and your healthcare team should weigh the risk versus benefit to determine if Topamax is appropriate for you. But keep in mind that weight loss during pregnancy isn’t typically recommended.
It’s important to let your prescriber know about your medical history and other medications you’re taking prior to starting Topamax. This helps them make sure it’s a safe treatment option.
What are alternatives to Topamax for weight loss?
There are several Topamax alternatives that are FDA-approved for weight loss. These include:
The best alternative depends on factors such as your health history, other medications, and weight-loss goals. Your healthcare provider can help you decide which treatment may be right for you.
Frequently asked questions
It’s best to avoid alcohol while taking Topamax. Combining the two can increase the risk of side effects, such as dizziness, confusion, and depression. Alcohol can also slow your metabolism and hinder weight-loss efforts. If you’re concerned about your ability to avoid or limit alcohol while taking Topamax, talk to your prescriber for guidance.
It isn’t common to gain weight while taking Topamax, but there are some rare reports of this happening. If you’re gaining weight while taking Topamax, reach out to your prescriber. Keep in mind that other medications and lifestyle changes can also lead to weight gain. Your prescriber can review your medication list and personal history to determine the cause as well as the best steps to take.
No, topiramate — the generic name for Topamax — is a different type of medication than Ozempic (semaglutide). Topiramate is an antiepileptic (anti-seizure) medication. It’s prescribed off-label on its own for weight loss. It’s also an ingredient in Qsymia, a combination weight-loss pill that also contains phentermine. Ozempic is a glucagon-like peptide-1 (GLP-1) receptor agonist. It’s FDA approved to treat Type 2 diabetes, but it’s also used off-label for weight loss.
It’s best to avoid alcohol while taking Topamax. Combining the two can increase the risk of side effects, such as dizziness, confusion, and depression. Alcohol can also slow your metabolism and hinder weight-loss efforts. If you’re concerned about your ability to avoid or limit alcohol while taking Topamax, talk to your prescriber for guidance.
It isn’t common to gain weight while taking Topamax, but there are some rare reports of this happening. If you’re gaining weight while taking Topamax, reach out to your prescriber. Keep in mind that other medications and lifestyle changes can also lead to weight gain. Your prescriber can review your medication list and personal history to determine the cause as well as the best steps to take.
No, topiramate — the generic name for Topamax — is a different type of medication than Ozempic (semaglutide). Topiramate is an antiepileptic (anti-seizure) medication. It’s prescribed off-label on its own for weight loss. It’s also an ingredient in Qsymia, a combination weight-loss pill that also contains phentermine. Ozempic is a glucagon-like peptide-1 (GLP-1) receptor agonist. It’s FDA approved to treat Type 2 diabetes, but it’s also used off-label for weight loss.
The bottom line
Topamax (topiramate) is an antiepileptic (anti-seizure) medication that causes weight loss in some people. Taking Topamax on its own for weight loss is considered an off-label use. But it’s combined with phentermine in an FDA-approved weight loss pill called Qsymia.
In studies, Topamax led to an average weight loss of 5% to 7% of starting body weight with minimal side effects. Unlike some other medications, Topamax’s weight-loss effect seems to continue past the 6-month mark. Higher doses of Topamax generally result in more weight loss but make side effects more likely.
Topamax may not be the best treatment option for everyone wanting to lose weight. Your healthcare team can help decide if this medication is a safe and appropriate option for you.
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References
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