Obesity Pharmacotherapy
6. Topiramate( Topamax)( mean change in BMI: 4-5 %)
a. Patient Selection: i. FDA approval 1. ≥ 2 years old for seizures 2. ≥ 12 years old for migraine prophylaxis 3. Other Considerations a. Consider for patients with i. poor satiety ii. food cravings iii. symptoms of binge eating disorder iv. weight gain due to atypical antipsychotic medication( eg aripiprazole / Abilify, olanzapine / Zyprexa, ziprasidone / Geodon, risperidone / Risperdal) AND do not have insulin resistance / prediabetes v. migraine headaches vi. night eating vii. seizures( discuss with neurologist: valproic acid + topiramate may increase risk of hyperammonemia) viii. mood swings who could benefit from mood stabilizer ii. CONTRAINDICATIONS – none iii. USE CAUTION 1. kidney stones 2. glaucoma 3. high risk for pregnancy due to fetal toxicity( and because topiramate may render oral contraceptives less effective) 4. metabolic acidosis – especially if on acetazolamide or with kidney disease or diabetes 5. active suicidal ideation 6. poor cognitive function and academic struggles b. To Start Topiramate: i. Check baseline metabolic panel to assess for metabolic acidosis and kidney. ii. Check baseline urine pregnancy test in females iii. Review warnings with patient and family. Paresthesia, Fatigue, Cognitive dysfunction – especially short-term memory loss and word finding( minimal with < 100 mg / day), Teratogenic potential, Symptoms of kidney stones, especially in summer months – encourage good hydration, Itching, Mood changes, Acute myopia iv. Start topiramate: 25 mg QAM for week 1, 50 mg QAM for week 2, then 75 mg QAM thereafter for preadolescents( consider dividing the dose depending on hunger pattern) and 100 mg QAM or 50-100 mg BID in adolescents; consider dosing at night if patient is fatigued at baseline or develops fatigue v. Include discussion of off-label use of topiramate and consent for treatment in documentation(“ We discussed that topiramate is not FDA approved for the indication of weight loss, but that it has been shown to help reduce weight in well controlled clinical studies. We reviewed the side effects of this medication, and that there are unknown side effects as well. Patient’ s parent / guardian consents to treatment.”) vi. Give family: topiramate patient info and off-label prescribing info vii. Almost always covered by all insurances.
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