Purpose This document summarizes PubMed-indexed clinical evidence on the safety and efficacy of longer-term phentermine monotherapy, with emphasis on cardiovascular risk, blood pressure, heart rate, valvular disease, pulmonary arterial hypertension, addiction potential, metabolic benefits, and weight loss outcomes. Regulatory Context Phentermine is FDA-approved for short-term use (typically defined as up to 12 weeks). Prescribing beyond
