Erectile dysfunction: Three rare cases of <i>Qsymia</i> side effect

Introduction: Sold under the brand name of Qsymia, the combination of phentermine and topiramate is a common medication used as an adjunct therapy for weight loss. Despite previous animal studies showing adverse effect to male rate infertility, sexual dysfunction including erectile dysfunction (ED) was not reported as an adverse effect for patient with obesity taking Qsymia. Case Report: We presented three cases of patients with obesity who reported ED as an adverse effect of Qsymia with two cases demonstrating reversibility with either discontinuation of the medication or supplementation with Sildenafil. All the patients have comorbidities for ED and two patients have predisposition to ED. We discussed the potential mechanisms of action for the different components of Qsymia causing ED in the three cases by reviewing previous literatures. Conclusion: Given the reversibility of ED and sufficient therapeutic effects, Qsymia should remain as the adjunct therapy for obesity along with diet modification and physical activities.