NAPLEX (North American Pharmacist Licensure Examination) Practice Exam 2026 - Free NAPLEX Practice Questions and Study Guide

Phentermine/topiramate ER is contraindicated in pregnancy due to teratogenic risk. Phentermine is classified as FDA pregnancy category X, indicating that there is evidence of fetal risk based on human data, while topiramate is classified as pregnancy category D, indicating positive evidence of human fetal risk based on adverse reaction data. Therefore, the combination of phentermine/topiramate ER poses a significant risk of birth defects and should be avoided in pregnant women or women planning to become pregnant. The other drug combinations listed do not have the same level of teratogenic risk as phentermine/topiramate ER.