Topamax for Weight Loss: Your GoodRx Guide
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.
Table of contents
First-choice approaches to help with weight loss generally involve changes to your diet and exercise habits. However, lifestyle changes may not always be enough. Studies show there’s a better chance for long-term weight management when medications are combined with a healthy lifestyle.
To date, there are a handful of medications that are FDA approved to help you reach or maintain your target body weight. But there are also medications prescribed off label for weight loss. This means they may help you lose weight, but they aren’t FDA approved to do so. One of these is a medication called Topamax (topiramate). But what is Topamax, and how does it work for weight loss?
What is Topamax?
Topamax is an anti-epileptic medication. It’s FDA approved to treat seizure disorders and prevent migraines. Weight loss is a common side effect reported by people taking Topamax for these conditions. As a result, several studies have investigated Topamax for weight loss.
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Topamax is only FDA approved for weight loss when combined with another medication called phentermine. This combination is available under the brand name Qsymia (phentermine / topiramate ER). As mentioned, you can take Topamax for weight loss on its own, but this is considered an off-label use.
Even though Topamax is an off-label medication for weight loss, it’s still commonly recommended by healthcare professionals. In a 2012 survey, 63% of the surveyed healthcare professionals reported prescribing Topamax for weight loss.
How does Topamax work for weight loss?
It’s unknown exactly how Topamax works for weight loss. But it seems to suppress your appetite, which causes you to eat less food. Topamax may also help you feel full sooner and reduce food cravings. Other studies show that Topamax may help lower levels of leptin, a hormone that tells your body to store fat.
Topamax may also improve insulin sensitivity in people taking antipsychotic medications, such as olanzapine (Zyprexa). Topamax helps prevent or lessen the weight gain that’s often seen with this class of medications.
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 body weight after 24 weeks (6 months) of treatment. More weight loss was reported with longer treatment and higher doses of Topamax.
Qsymia, the combination of Topamax and phentermine, seems to be the most effective FDA-approved weight-loss pill. But neither Topamax or Qsymia seem to be as effective as the newer injectable weight-loss medications, such as Wegovy (semaglutide) and Zepbound (tirzepatide).
A holistic approach: Combining weight-loss medication with lifestyle changes can improve your chances of success. Here, one person shares how a new diet and mindset helped keep him at his ideal weight.
Weight-loss pills: Learn more about FDA-approved pills for weight loss to help you make the best choice for your needs.
What it’s like to take Qsymia: Qsymia is an effective oral option for those looking to lose weight. Three women discuss the benefits and downsides of taking it.
What’s the best Topamax dosage for weight loss?
Since it isn’t approved for weight loss, there also isn’t an approved Topamax dosage for this use. In studies, effective doses for Topamax taken by itself 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. Qsymia can take longer, with typical 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 also seem to result in more weight loss but may cause more side effects. But 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 personal health needs.
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. For this reason, 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 (e.g., burning, tingling, numbness), altered sense of taste, and slowed thinking and movements.
Other notable side effects include:
Memory and concentration problems
Feeling nervous
Mood changes
Dry mouth
Changes in vision
Nausea
Dizziness
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. They may need to make changes to your medication to manage them.
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.
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.
When should you talk to your healthcare team about Topamax?
If you’re interested in taking medication to help you manage your body weight, talk to a healthcare professional. They can help determine if Topamax is a good option for you. They can also discuss the pros and cons of other available treatment options to help you make an informed choice.
If you’re taking Topamax and have any side effects that are affecting your day-to-day routine, let your prescriber know. They may need to adjust your treatment.
An important thing to note is that rapid weight changes over a short period of time can also indicate a medical problem. If you notice dramatic changes to your weight without a known cause, it’s best to seek medical care right away.
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 it is possible in rare cases. If you’re gaining weight while taking Topamax, reach out to your prescriber. Keep in mind that other medications can cause weight gain. Your prescriber can review your medication list and personal history to determine the cause as well as the best steps to take.
The bottom line
Topamax (topiramate) is an anti-epileptic 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 medication called Qsymia.
In studies, Topamax seems to be effective for weight loss and well-tolerated by most people. 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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