Five drugs were recently compared to treat obesity, and four were deemed to help pre-menopausal women in the study achieve at least 5 percent weight loss. Two of these four are not approved in the United States.
In a year-long study released yesterday in the International Journal of Obesity, a total of 174 women randomly received diethylpropion (DEP), fenproporex (FEN), mazindol (MZD), fluoxetine (FXT), sibutramine (SIB) or placebo (PCB) as treatment for obesity. Anthropometry, safety, metabolic and cardiovascular parameters were also examined. On average participants lost about 8 pounds amongst the variety of drugs, expect with placebo where the average was about 3 pounds and FXT average was 2.5 pounds.
“Diet and physical activity were encouraged,” but not required.
“Ten (33.3%) women lost 5% of their initial weight with PCB, compared with 20 (71.4% P<0.001) with DEP, 20 (69% P<0.02) with FEN, 21 (72.4% P<0.01) with MZD, 22 (73.3% P<0.001) with SIB, and 10 (35.5%) with FXT.”
The study, conducted at Parana University in Brazil, also showed “each medically treated group experienced more adverse events compared with PCB.” The incidence is shown to be <0.001. Constipation, anxiety and irritability were among the negative effects.
This is interesting considering two of the four drugs showing improvement are no longer available in the United States. SIB, for instance, has a clear warning on the Medline Plus website:
“Sibutramine is no longer available in the U.S. The manufacturer has decided to stop producing sibutramine based on information from a recent clinical study. In this study, people taking sibutramine had an increased risk of cardiovascular events such as heart attack and stroke. If you are currently taking sibutramine, you should stop taking this medication and call your doctor to discuss switching to another treatment for weight loss or maintenance of weight loss.”
DEP is prescribed mainly for decreasing appetite. According to Medline Plus, it is usually prescribed for a short-term basis, around three weeks. The side effects listed are dry mouth, unpleasant taste, restlessness, anxiety, dizziness, depression, tremors, upset stomach, vomiting and increased urination. It also states that the drug may be habit-forming and may affect the blood sugar of diabetic patients.
FEN isn’t listed in Medline Plus, and is not authorized for use in the United States, however, is available in diet and weight loss supplements on the internet. Fenproporex is a stimulant. The U.S. Food and Drug Administration states on its’ website, “Fenproporex, an amphetamine derivative, is a schedule IV controlled substance and could show up positive for amphetamines in a urinalysis. Serious adverse effects of stimulants include headache, tachycardia, increased breathing rate, increased blood pressure, fever, sweating, diarrhea, constipation, blurred vision, impaired speech, dizziness, uncontrollable movements or shaking, insomnia, numbness, palpitations, arrhythmia and possible sudden death.”
MZD is not listed in Medline Plus either. Information at the FDA website also lists MZD as a stimulant. While there is no other readily useable information at the FDA site, a 2006 report does show that these amphetamine drugs are typically being used longer than the three week period recommended, perhaps the reason for the year-long study.
Despite all of these potential side effects, participants in this study with at least 5 percent weight loss showed less depression, anxiety and binge-eating, as well as reported an improved quality of life. There is no word on whether a follow-up study would be warranted to see quality of life once taken off the drugs.