NEW YORK - The death of a Massachusetts woman who took diet drugs to fit into her wedding dress has increased scrutiny of an unapproved but widely used drug mixture popularly known as fen-phen.

Before Mary Linnen of Quincy died in February from a heart and lung disorder, drugmaker Wyeth-Ayerst Laboratories Inc. had warned doctors that taking its appetite suppressant, fenfluramine, with the competing phentermine is "not recommended."

The combined drug, banned in Sweden, is popular at such weight-loss centers as Nutri/System, whose doctors wrote several thousand fen-phen prescriptions last year, company spokesman Joseph DiBartolomeo said.