Fenfluramine/phentermine

The drug combination fenfluramine/phentermine, usually called fen-phen, was an anti-obesity treatment that utilized two anorectics. Fenfluramine was marketed by American Home Products (now known as Wyeth) as Pondimin, but was shown to cause potentially fatal pulmonary hypertension and heart valve problems, which eventually led to its withdrawal and legal damages of over $13 billion. Phentermine was not shown to have harmful effects.

Fenfluramine acts as a serotonin releasing agent, phentermine as a norepinephrine, dopamine and serotonin releasing agent.