What is Fen-Phen?

Fen-Phen (or Phen-Fen) was an off-label combination of two weight loss medications – phentermine (“phen”) and fenfluramine (“fen”) that grew popular in the late 80s and early 90s. The duo gained renown for its ability to help patients shed weight quickly and easily.

However, safety concerns soon emerged and fenfluramine was removed from the market in 1997.

Fenfluramine (and its more potent cousin, dexfenfluramine) were withdrawn after studies linked these medications to an increased risk of pulmonary hypertension and heart valve disease. While phentermine was never implicated in these studies, the combination was no longer available after “fen” had been discontinued.

Click here to read more about Fen-Phen and its history.