What are weight loss medications?

Indications and Procedures

By the mid-1990’s, several drugs had come onto the market showing promise in helping people achieve weight loss. The most widely sought and prescribed of these were Fen-Phen (combining serotonergic fenfluramine and amphetamine-like phentermine) and Redux (dexfenfluramine, with similar properties and actions to fenfluramine). Fen-Phen inhibited the brain’s utilization of the neurochemical serotonin, which acts on the brain’s appetite control center in the hypothalamus, and suppressed appetite directly, much as traditional over-the-counter diet pills do. Other drugs, less widely used, included phentermine, mazindol, and fluoxetine.

The hope and early evidence were that these medications would produce improved cardiac function, cholesterol and triglyceride profiles, blood sugar concentrations, and blood pressure; assist in the treatment of bulimia; and reduce weight in the obese and prevent weight gain in those at high risk for it, such as individuals who recently have quit smoking. The drugs were intended to assist those with morbid obesity, obese persons with serious medical conditions, and obese persons who had failed to manage their weight using more conservative nutritional and behavioral methods. At no point did researchers intend the medications as quick fixes for those unwilling to exercise or unwilling to change their eating habits. Nevertheless, many physicians prescribed them to patients who were not significantly obese or who were merely overweight.

Uses and Complications

Multiple studies across many different populations have tended to show the same results: Measurable weight loss in those taking the drugs was between 5 and 15 percent, with weight regained one year after patients had stopped taking the drug. The medications had few initial side effects—dry mouth, constipation, and drowsiness being the most common—and were unlikely to become physically addicting.

Health providers across all disciplines were particularly concerned, however, that some patients were coming to rely on these medications as alternatives to the sustained, hard work of developing lifestyle habits of healthy, proportional eating and exercise. In addition, concerns grew over the drugs’ potential to cause neurotoxicity and primary pulmonary hypertension. Fen-Phen, in particular, was responsible for numerous reports of valvular heart
disease and pulmonary hypertension.

Perspective and Prospects

In 1997, the Food and Drug Administration (FDA) withdrew approval of Fen-Phen and Redux for treating obesity, and their marketing and distribution were discontinued. Class-action lawsuits were filed—former Fen-Phen users alone have filed approximately fifty thousand lawsuits against the makers of the drug—and large settlements were reached for those who had used Fen-Phen and other such drugs.

The government then set its sights on dietary products containing ephedra. Manufacturers claimed that ephedra, a botanical source of ephedrine, is a “fat-burning” supplement that could boost energy and enhance athletic performance, but reports began to surface about seizures, strokes, heart attacks, and even deaths in otherwise healthy users. In 2003, the FDA banned the use of ephedra.

Bibliography

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Finn, R. “Pharmacotherapy May Help Some Obese Teens.” Internal Medicine News 38, no. 19 (June, 2005): 45.

Marcovitz, Hal. Diet Drugs. Farmington Hills, Mich.: Lucent Books, 2007.

Mitchell, Deborah R., and David Dodson. The Diet Pill Guide: A Consumer’s Book to Prescription and Over-the-Counter Weight-Loss Pills and Supplements. New York: St. Martin’s Griffin, 2002.

Peikin, Steven R. The Complete Book of Diet Drugs: Everything You Need to Know About Today’s Prescription and Over-the-Counter Weight Loss Products. New York: Kensington Books, 2002.

Whelan, S., and T. A. Wadden. “Combining Behavioral and Pharmacological Treatments for Obesity.” Obesity Research 10, no. 6 (June, 2002): 560-574.