Diet pills fenfluramine

Figure 4.1 The chemical structure of amphetamine and fenfluramine are illustrated here. Fenfluramine (bottom) is a diet pill that is very similar in structure to amphetamine (top). Fenfluramine is an appetite suppressant, like amphetamine, but it does not have stimulant effects. Fenfluramine was proposed as a safer alternative to amphetamine and was very effective in causing weight loss, especially when used in combination with phentermine. Unfortunately, fenfluramine eventually led to devastating side effects, which led to its being withdrawn from the U.S. market.

Additional ADRs linked to diet pills include psychosis myocardial ischemia drug interactions, such as the interaction of fenfluramine with imipramine, fenfluramine with amitriptyline or desipramine, or the toxic reaction between fluoxetine and phentermine and the release of serotonin while inhibiting its reuptake, contributing to hyperserotonin reactions. When the next craze takes hold of patients and their physicians, hopefully physicians and pharmacists will take a more vocal position and recommend restraint, xmtil some proof of efficacy and lack of toxicity is shown for new faddish off-label combinations. 

The diet pills developed to replace amphetamines became known as anorectics or appetite suppressants and are central nervous system stimulants. The FDA approved phentermine in 1959, fenfluramine in 1973, and dexfenfluramine in 1996. 

Spending for prescription diet pills reached a record of approximately 467 million in 1996, according to the American Society of Bariatric Physicians, an association focused on weight loss. Fen-phen sales accounted for much of that record. After the withdrawal of dexfenlu-ramine and fenfluramine from the market, diet pill sales dropped. 

Anorectic drugs, appetite suppressants, are also found in diet pills such as fenfluramine (or fen-phen), phenter-mine, diethylproprion, and mazindol. Perhaps the most hazardous ingredient commonly found in diet pills until a few years ago was ephedrine. Ephedrine is more commonly known as one of the precursor chemicals needed to manufacture methamphetamine. 

Wyeth ( 16 billion in sales). Formerly known as American Home Products, this company headquartered in Madison, New Jersey, makes many well-known OTC drugs such as Robitussin and Advil. The company first used machines to mass-produce tablet pills in 1872 and supplied the polio vaccine for early trials in the 1950s. It produced a diet drug called fenfluramine that when combined with other drugs into a form known as fen-phen caused health problems and was withdrawn from the market. It makes Premarin and Prem-pro for estrogen replacement, Effexor for depression and anxiety disorders, Ativan for anxiety and insomnia, and Enbrel for arthritis. 

---