Topiramate

Written byKaitlin Ahern
Published 03/31/2025

Topiramate (Topamax®) is an oral medication used to manage seizures and migraines by balancing electrical and nerve activity in the brain.

Basics

Topiramate is the active ingredient in the brand-name medication Topamax®, an anticonvulsant medication used to treat seizures and prevent migraines by stabilizing electrical activity in the brain and reducing abnormal brain cell firing. 

The drug is FDA-approved to treat epilepsy, including partial onset and generalized tonic-clonic seizures, and for migraine prevention in adults and adolescents ages 12 and older. 

Common side effects include dizziness, paresthesia, fatigue, weight loss, and trouble concentrating, and it carries a warning for increased risk of metabolic acidosis (a condition where too much acid builds up in the body) and kidney stones.

Approved Uses*

Topamax (topiramate) is indicated for:

  • Epilepsy: initial monotherapy for the treatment of partial-onset or primary generalized tonic-clonic seizures in patients 2 years of age and older; adjunctive therapy for the treatment of partial-onset seizures, primary generalized tonic-clonic seizures, or seizures associated with Lennox-Gastaut syndrome in patients 2 years of age and older

  • Preventive treatment of migraine in patients 12 years of age and older

Drug Category*

The drug category for topiramate is anticonvulsant.

Side Effects*

Epilepsy: Most common (≥10% more frequent than placebo or low-dose Topamax) adverse reactions in adult and pediatric patients were:

  • Tingling

  • Anorexia

  • Weight loss

  • Speech disorders/Related speech problems

  • Fatigue

  • Dizziness

  • Sleepiness

  • Nervousness

  • Slowing down of physical and mental activities

  • Abnormal vision

  • Fever

Migraine: Most common (≥5% more frequent than placebo) adverse reactions in adult and pediatric patients were:

  • Tingling

  • Anorexia

  • Weight loss

  • Difficulty with memory

  • Taste perversion

  • Diarrhea

  • Loss of sensation

  • Nausea

  • Abdominal pain

  • Upper respiratory tract infection

Interactions & Contraindications*

  • Drug interactions: contraceptives, lithium

Warnings & Precautions*

  • Acute myopia and secondary angle closure glaucoma

  • Visual field defects

  • Oligohidrosis and hyperthermia

  • Metabolic acidosis

  • Suicidal behavior and ideation

  • Cognitive/Neuropsychiatric adverse reactions

  • Fetal toxicity

  • Withdrawal of AEDs

  • Decrease in bone mineral density

  • Negative effects on growth (height and weight)

  • Serious skin reactions

  • Hyperammonemia/Encephalopathy

  • Kidney stones

  • Hypothermia has been reported with and without hyperammonemia during topiramate treatment with concomitant valproic acid use

Boxed Warning*

Boxed Warning not available for this drug .

Cost

The cost of topiramate varies depending on factors such as your insurance plan, which pharmacy you use, the dosage, and quantity. Without insurance, generic topiramate may cost around $70 and $165 for a month’s supply, although there are coupons and savings programs that may help you pay for the drug. Brand-name Topamax may cost between $475 and $540 for a month’s supply. Insurance plans may cover all or some of the cost of these medications.

Hers offers access to personalized Weight Loss Medication Kits. Kits may contain one of several combinations of medications that help support weight loss, such as a compounded version of topiramate**. These medication kits start at $69 per month with a monthly subscription plan paid in full. The cost includes a provider consultation, ongoing provider support, and access to the Hers app. 

**Compounded medications are not approved or evaluated for safety, effectiveness, or quality by the FDA. 

Alternatives

Several other drugs are available that can help manage seizures and prevent migraines. Some medications may be better suited to you than others. If you’re interested in finding an alternative to topiramate, talk with your provider to learn more about other medications that may work well for you.

Drugs that may be prescribed to treat both seizures and migraines include:

  • Depakote® (divalproex sodium) 

  • Elepsia® or Keppra® (levetiracetam)

  • Fycompa® (perampanel)

  • Lamictal® (lamotrigine)

  • Lyrica® (pregabalin)

  • Neurontin® (gabapentin)

  • Tegretol® (carbamazepine)

  • Trileptal® (oxcarbazepine)

  • Vimpat® (lacosamide)

  • Zonegran® (zonisamide)

Additional drugs that may be prescribed to manage seizures include:

  • Banzel® (rufinamide)

  • Dilantin® (phenytoin)

  • Klonopin® (clonazepam)

  • Phenobarbital

  • Sabril® (vigabatrin)

Topiramate is sometimes prescribed off-label to support weight loss. Other medications that may be prescribed (on or off-label) to aid with weight loss include:

Injectable medications:

  • Compounded semaglutide***

  • Ozempic® (semaglutide)

  • Saxenda® (liraglutide)

  • Wegovy® (semaglutide)

  • Zepbound® (tirzepatide)

Oral medications:

  • Contrave® (naltrexone hydrochloride and bupropion hydrochloride)

  • Metformin

  • Qsymia® (phentermine and topiramate extended-release)

  • Rybelsus® (semaglutide)

  • Xenical® or Alli® (orlistat)

***Compounded semaglutide is not approved or evaluated for safety, effectiveness, or quality by the FDA.

FAQs

What does topiramate do for weight?

Topiramate is sometimes prescribed off-label for weight loss because it can decrease appetite and cause feelings of fullness after eating to last longer.

How long does it take to lose weight on topiramate?

When combined with a healthy eating plan and regular physical activity, topiramate can lead to gradual weight loss. Everyone may respond differently to the medication, but research suggests you may see results within four months of starting the drug. But more significant weight loss is seen with longer treatment durations.

What’s the best topiramate dosage for weight loss?

Topiramate is prescribed off-label for weight loss, so there is no official dose recommendation. However, research suggests that higher doses (192 to 384 mg) are more effective for weight loss than lower doses. But higher doses come with a higher risk of side effects.

What’s the difference between topiramate and phentermine?

Topiramate and phentermine are sometimes prescribed together, but they are two different types of drugs. Topiramate is an anti-seizure medication used to treat seizures and prevent migraines. It works by stabilizing electrical activity in the brain and reducing abnormal brain cell firing. It’s sometimes prescribed off-label for weight loss because it can help reduce appetite and cause feelings of fullness to last longer after you eat, but the reason it does so isn’t well understood.

Phentermine, on the other hand, is prescribed to help treat obesity. It is a central nervous system stimulant, which means it increases heart rate and blood pressure while reducing hunger.

How to Get Topiramate

Topiramate is available with a prescription from a licensed healthcare provider. Your provider will determine if the medication is right for you based on factors like your symptoms and medical history. 

If you’re interested in topiramate for weight loss, you can connect with a licensed healthcare provider on the Hers platform. Providers are trained in weight management and can help create a personalized weight loss treatment plan that incorporates both medication and healthy lifestyle changes. 

For those who qualify, Hers offers Oral Weight Loss Medication Kits starting at $69 a month. Your kit may contain compounded topiramate, along with other prescription medications to help support you on your weight loss journey. 

When you access weight loss medication through the Hers platform, your medication is shipped directly to your door. You get all the supplies you need, along with instructional videos, ongoing provider support through the app, and a wealth of holistic health resources like meal plans, recipes, and fitness content. 

Learn more about Weight Loss by Hers

8 Sources

  1. Ben-Menachem E, et al. (2003). Predictors of weight loss in adults with topiramate-treated epilepsy. https://pubmed.ncbi.nlm.nih.gov/12690085/
  2. Bray GA, et al. (2003). A 6-month randomized, placebo-controlled, dose-ranging trial of topiramate for weight loss in obesity. https://onlinelibrary.wiley.com/doi/10.1038/oby.2003.102
  3. Epilepsy Foundation. (n.d.). Summary of anti-seizure medications. https://www.epilepsy.com/stories/summary-anti-seizure-medications
  4. GoodRx. (2024). How much is topiramate without insurance? https://www.goodrx.com/topiramate/how-much-topiramate-costs-without-insurance
  5. Kramer CK, et al. (2011). Efficacy and safety of topiramate on weight loss: a meta-analysis of randomized controlled trials. https://onlinelibrary.wiley.com/doi/10.1111/j.1467-789X.2010.00846.x
  6. National Library of Medicine. (2023). Phentermine and topiramate. https://medlineplus.gov/druginfo/meds/a612037.html
  7. Rollo E, et al. (2023). Antiseizure medications for the prophylaxis of migraine during the anti-CGRP drugs era. https://pmc.ncbi.nlm.nih.gov/articles/PMC10514541/
  8. Tonstad S, et al. (2005). Efficacy and safety of topiramate in the treatment of obese subjects with essential hypertension. https://pubmed.ncbi.nlm.nih.gov/16018851/
Reference

*This information is from the label for brand name Topamax®. See the Full Prescribing Information for more complete information. Topiramate, the active ingredient in Topamax, may also be the active ingredient in other medications, and this information may not be accurate for all medications that include the active ingredient topiramate.

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.

All trademarks are the property of their respective owners. Use of third-party trademarks is for informational purposes only and does not imply endorsement or affiliation with Hims, Inc.