If you’re trying to lose weight, chances are you’ve traveled down the interweb’s rabbit holes researching any and all prescription medications for weight loss and over-the-counter supplements. It’s easy to get lost in Google—you’ve likely read about and tried every diet out there. You may have come across the prescription drug topiramate (or Topamax).
Topiramate is an anticonvulsant medication used to treat certain seizures, epilepsy, and migraines. Ongoing research is also being done on its efficacy in treating alcoholism, post-traumatic stress disorder (PTSD), and binge-eating disorder. The drug was first synthesized in 1979 and received approval from the Food and Drug Administration (FDA) in 1996 as an antiepileptic drug.
As more and more patients started taking topiramate, the medical community began noticing weight loss as a side effect of topiramate. They were intrigued by the idea it might help treat conditions like overweight and obesity, and asked: Could topiramate help reverse this growing epidemic?
In 2012, after years of clinical trials, the FDA approved Qsymia—a controlled-release combo of topiramate and phentermine—for weight management. Phentermine (another medication that you may be familiar with) helps activate the sympathetic nervous system and can suppress appetite. Combined with topiramate, the duo may also increase energy expenditure—meaning the number of calories your body burns.
We're here to answer your questions if you’re curious about topiramate weight loss and its possible side effects. Let’s get to it.
Obesity has almost tripled since 1975, according to the World Health Organization, and excess weight has been linked to an estimated 3 million deaths annually worldwide. It’s one of the leading contributors to preventable deaths in the United States. These numbers are one of the reasons drugs like topiramate are being prescribed off-label to support weight loss—in addition to diet and exercise.
Topiramate by itself can be prescribed off-label as a weight loss drug. A paper on the first clinical trial for use of the drug for obesity, published in 2003, found that topiramate produced significant weight loss in participants. Among 385 healthy obese participants, those on topiramate lost an average of 6.3 percent of their body weight over 24 weeks, compared to a placebo group that dropped only 2.6 percent.
Perhaps even more intriguing: The people in the study taking topiramate didn’t plateau during the study, which suggests that the weight management benefits would continue (though it may mean taking the medication for an extended period of time to get the maximum results).
With any medication you take, there are risks of side effects. Truth be told, weight loss is a side effect of the topiramate in and of itself. So when taking this medication, if you suffer from overweight or obesity, losing weight is the most common side effect you’ll experience while on it.
But, although rare, there are other serious side effects we want you to be aware of when taking topiramate for weight loss. Contact your health care provider immediately if they do happen:
Paresthesia (burning, prickling, or tingling sensations)
Eye redness or pain
Generalized slowing of mental and physical activity
Increased eye pressure
Menstrual changes or pain
Speech or language problems
Trouble concentrating or paying attention
Unusual tiredness or weakness
We totally get it; after reading the side effects, you may be thinking ehhhh is this drug right for me? The best person to consult may be your Found health care provider. They’ll be able to cover the side effects of using topiramate for weight loss in-depth. They’ll also be able to talk about what other medications and supplements you shouldn't take when on topiramate. In addition, here are some lifestyle guidelines to keep in mind:
Don’t get dehydrated. The FDA cautions that in some cases during clinical trials, patients didn’t sweat normally, and their base temperature increased. Drink plenty of water. Also, if you feel warmer than normal, tell your doctor right away.
Steer clear of ketogenic (keto) diets. A keto plan is essentially high in fat and low in carbohydrates. Taking topiramate can cause metabolic acidosis—in other words, too much acid in the body, while a keto diet can cause ketoacidosis, leading to even more acid. And too much acid can cause kidney stones, kidney disease, or even kidney failure. Taking topiramate while following a keto diet could compound the problem and increase the risk of acid overload.
Reduce salt intake. The National Institute of Diabetes and Digestive and Kidney Diseases warns that sodium can increase the risk of developing kidney stones. (Check out the keto info above.) So it’s best to watch how much salt you’re getting in your diet to avoid upping your risk of kidney stones. The Dietary Guidelines for Americans recommends less than 2,300 mg of salt daily—that’s about one teaspoon a day.
Watch out for certain birth control pills. A small study published in 1997 in the journal of the International League Against Epilepsy, Epilepsia, looked at the efficacy of oral contraceptives among women taking topiramate. Researchers found that while the birth control pill was still just as effective, they did see some breakthrough bleeding between periods. However, more recent studies suggest that topiramate may reduce the effectiveness of estrogen-containing contraceptives. You may want to consider progestin-only birth control. Similarly, if you’re pregnant or planning on becoming pregnant, in 2011 the FDA issued a warning that data showed an increased risk of cleft lip or palate with women treated with topiramate.
Again, be sure to tell your health care provider your entire medical history and any medication or supplements you’re on for guidance on what not to take with topiramate.
Studies indicate that topiramate can be taken in low doses—typically 25 mg—to begin with to see how well your body tolerates it. It can be bumped up to 50 mg daily. The doses are taken evenly, twice a day, and are typically increased weekly.
A study in the International Journal of Obesity found that 60 weeks of treatment led to an average of more than 9 percent loss in body weight while taking 192 mg of topiramate daily. Researchers concluded that lower doses of topiramate for weight loss may have a beneficial result over a longer period of time. As a note, this study looked at topiramate taken alone, finding people can lose weight on lower doses and in combination with behavior change. But of course, the effective dose varies in individuals.
The medication is also offered in an extended-release form called topiramate XR. It comes in the same daily dose as the original medication but only needs to be taken once a day. So, like all of us, if life gets busy, it may be easier for you to remember to take that one dose daily instead of two times a day for topiramate weight loss.
It’s clear topiramate weight loss is real and is worth considering when choosing what weight loss medication is right for you.
Found offers a science-backed approach to weight care that's based on your unique biology, psychology, lifestyle, and prescription medication needs. On average, Found members lose 10% of their body weight by month six and are able to keep it off. In total, members have lost nearly 800,000 pounds. To start your journey with Found, take our quiz.
Blanco JC, Khatri A, Kifayat A, Cho R, Aronow WS. Starvation Ketoacidosis due to the Ketogenic Diet and Prolonged Fasting - A Possibly Dangerous Diet Trend. Am J Case Rep. 2019 Nov 22;20:1728-1731.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6883983/
Bray, G.A., Hollander, P., Klein, S., Kushner, R., Levy, B., Fitchet, M. and Perry, B.H. (2003), A 6-Month Randomized, Placebo-Controlled, Dose-Ranging Trial of Topiramate for Weight Loss in Obesity. Obesity Research, 11: 722-733. https://onlinelibrary.wiley.com/doi/10.1038/oby.2003.102
The U.S. Food and Drug Administration. 4 Mar. 2011. FDA Drug Safety Communication: Risk of oral clefts in children born to mothers taking Topamax (topiramate). https://www.fda.gov/drugs/drug-safety-and-availability/fda-drug-safety-communication-risk-oral-clefts-children-born-mothers-taking-topamax-topiramate
Hoy SM. TopiramateExtended Release: A Review in Epilepsy. CNS Drugs. 2016 Jun;30(6):559-66.https://pubmed.ncbi.nlm.nih.gov/27224993/
Moradi S, Kerman SR, Mollabashi M. The effect of topiramate on weight loss in patients with type 2 diabetes. J Res Med Sci. 2013 Apr;18(4):297-302.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3793374/
National Library of Medicine. 2022. TOPAMAX - topiramate. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=21628112-0c47-11df-95b3-498d55d89593
National Institute of Diabetes and Digestive and Kidney Disease. 2017. U.S. Department of Health and Human Services. https://www.niddk.nih.gov/health-information/urologic-diseases/kidney-stones/eating-diet-nutrition
Rosenfeld WE, Doose DR, Walker SA, Nayak RK. Effect of topiramate on the pharmacokinetics of an oral contraceptive containing norethindrone and ethinyl estradiol in patients with epilepsy. Epilepsia. 1997 Mar;38(3):317-23. https://pubmed.ncbi.nlm.nih.gov/9070594/
Singh J, Kumar R. Phentermine-topiramate: First combination drug for obesity. Int J Appl Basic Med Res. 2015 May-Aug;5(2):157-8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4456896/
World Health Organization. 2021. Obesity and overweight. https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight