What is the effect of Topiramate (Topamax) 200mg on weight loss?

From the Guidelines

Topiramate at a dose of 200mg daily can be effective for weight loss, though it's not FDA-approved specifically for this purpose, and its use should be considered in the context of overall morbidity, mortality, and quality of life. This medication, primarily used for seizures and migraine prevention, causes weight loss through multiple mechanisms including appetite suppression, taste alteration, and increased feelings of fullness 1. For weight management, patients typically start at 25mg daily and gradually increase to 200mg over 8 weeks to minimize side effects. The medication is usually taken in two divided doses. Common side effects include tingling sensations, altered taste, fatigue, difficulty concentrating, and kidney stones. Patients should drink plenty of water to reduce kidney stone risk. Blood monitoring may be necessary as topiramate can cause metabolic acidosis. This medication should be used alongside diet and exercise, not as a standalone treatment. Patients should be aware that topiramate is used off-label for weight loss, and its effects may diminish if discontinued. Anyone considering topiramate for weight loss should consult with their healthcare provider, as it's not appropriate for everyone, particularly pregnant women due to birth defect risks.

The use of topiramate for weight loss is supported by studies such as the EQUIP, CONQUER, and SEQUEL trials, which demonstrated significant weight loss with the combination of phentermine and topiramate extended-release 1. However, the most recent and highest quality study, the 2022 American Gastroenterological Association clinical practice guideline on pharmacological interventions for adults with obesity, suggests using semaglutide 2.4 mg with lifestyle modifications as the first-line treatment for obesity, and phentermine-topiramate ER as a conditional recommendation 1.

Key considerations for the use of topiramate for weight loss include:

• Starting with a low dose and gradually increasing to minimize side effects
• Monitoring for common side effects such as tingling sensations, altered taste, and kidney stones
• Using the medication alongside diet and exercise, not as a standalone treatment
• Avoiding use in pregnant women due to birth defect risks
• Considering alternative treatments, such as semaglutide 2.4 mg, as first-line therapy for obesity.

From the FDA Drug Label

The most common dose-related adverse events at dosages of 200 to 1,000 mg/day were: fatigue, nervousness, difficulty with concentration or attention, confusion, depression, anorexia, language problems, anxiety, mood problems, and weight decrease Table 8: Incidence (%) of Dose-Related Adverse Events From Placebo-Controlled, Add-On Trials in Adults with Partial Onset Seizuresa Topiramate Dosage (mg/day) Adverse EventPlacebo(N=216)200(N=45)400(N=68)600-1,000(N=414) ... Weight Decrease 34913

The effect of Topiramate (Topamax) 200mg on weight loss is that weight decrease is a dose-related adverse event, with an incidence of 3% at 200mg/day and 9% at 400mg/day, and 13% at 600-1000mg/day 2.

From the Research

Effect of Topiramate on Weight Loss

• Topiramate has been associated with weight loss in various studies, with the amount of weight loss related to factors such as treatment duration and baseline body mass index (BMI) 3.
• A meta-analysis of randomized controlled trials found that patients treated with topiramate lost an average of 5.34 kg of additional weight compared to placebo, with treatment duration and dosage associated with the efficacy of topiramate treatment 4.
• In a clinical case series, topiramate was effective in reducing weight in 10 out of 12 patients with affective disorders, with a mean weight loss of 7.75 kg at six months and 9.61 kg at 12 months 5.
• A randomized clinical trial found that topiramate induced weight loss and improved glycemic control in obese patients with type 2 diabetes, with a mean weight loss percentage of -3.02% compared to +0.32% in the placebo group 6.
• In prepubertal children with epilepsy, topiramate was found to decrease body mass index, fasting insulin-to-glucose ratio, and serum cortisol and leptin levels, which may be key factors in weight loss due to topiramate 7.

Dosage and Weight Loss

• The study by 5 used a final dose of topiramate varying from 200 to 600 mg/day, with effective weight loss in 10 out of 12 patients.
• The study by 4 evaluated trials using topiramate 96-200 mg/day and found higher weight loss in trials with longer treatment duration.
• The study by 7 used a daily dose of 5 mg/kg topiramate in prepubertal children with epilepsy, with significant decreases in body mass index and serum cortisol and leptin levels.

Factors Influencing Weight Loss

• Baseline body mass index (BMI) has been found to be a factor influencing weight loss, with higher baseline BMI associated with greater weight loss 3, 4.
• Treatment duration has also been found to be a factor, with longer treatment duration associated with greater weight loss 4, 5.
• The role of daily dosage and gender of patients is controversial, with some studies finding no significant effect 3.