Redux (dexfenfluramine hydrochloride) was a popular weight loss aid prescribed for moderately overweight to obese patients. Popular in the 1990s, Redux caused weight loss by increasing serotonin levels in the brain, thereby reducing appetite. Despite its possible benefits, Redux was withdrawn from the market due to its side effects, which included heart valve damage and other fatal conditions. Learning about the history of Redux for weight loss helps highlight the potential risks of using drugs to lose weight.
Redux was an appetite suppressant often used in conjunction with the stimulant phentermine and made up one half of the diet drug commonly called Fen-Phen. In combination with diet and exercise, Redux was promoted as an oral appetite suppressant that could help reduce caloric intake and lead to weight loss.
Redux primarily affects serotonin — a neurotransmitter that regulates sleep, mood and appetite. According to Time magazine, Redux stimulates the production of serotonin, thereby creating the sensation of satisfaction and fullness.
Unfortunately, it was the drug's effect on serotonin that was likely responsible for its dangerous side effects. The American Heart Association states that the increase of serotonin caused by Redux is to blame for primary pulmonary hypertension and heart valve damage in patients taking the drug.
Redux and other drugs containing fenfluramine are now known to cause serious and potentially fatal side effects. According to the National Institutes of Health, fenfluramine and its derivatives are potent causal factors in mitral and aortic valvular heart disease.
Primary pulmonary hypertension — a disease characterized by high blood pressure in the small arteries of the lungs — was also associated with use of Redux. Some patients also experienced serious mood-related symptoms like depression and anxiety.
Fenfluramine was approved for use in the U.S. in 1973. Due to a high incidence of side effects like depression, it was rarely used until the 1980s, when it was suggested that the drug be taken in combination with phentermine to combat side effects.
After being haled as a miracle diet drug in the mid-1990s, serious heart-related side effects were reported in patients taking the drug, causing fenfluramine and its derivatives to be withdrawn from the market.
The belief that weight loss can be achieved with little or no effort can lead to dangerous consequences, as proven by Redux. To date, a combination of healthy eating and exercise is the only method proven both safe and effective for long-term weight management. Learning about the history of drugs like Redux helps remind consumers about the potential risks of relying on diet medications to lose weight.