The consumer group Public Citizen is asking the government to ban the prescription diet drug Meridia, arguing that its risks outweigh its benefits.
The Food and Drug Administration reports that 25 people worldwide who were taking the drug have died, though it is not known whether those deaths were related to Meridia. Sixteen of the deaths were related to heart problems.
A spokeswoman for the manufacturer, Abbott Laboratories, said the company knows of 32 deaths of people taking Meridia, including 28 in this country. But Melissa Brotz said there does not appear to be a pattern suggesting the drug was to blame.
"There is no evidence of a link in any of the deaths to the drug," Brotz said, noting even the 16 cardiac deaths do not all stem from the same problem.
Public Citizen petitioned the FDA on Tuesday to pull the drug, known chemically as sibutramine, calling it "unacceptably dangerous." The group noted that FDA's scientific advisers recommended against the initial approval because the drug had only minimal weight-loss benefits but increased blood pressure and heart rate for some patients.
"The effect of sibutramine in promoting weight loss is meager and it is not known if this drug, or any diet drug for that matter, can be taken safely for a long enough period of time to reduce the morbidity and mortality associated with obesity," wrote Dr. Sidney Wolfe and two of his colleagues on behalf of Public Citizen Health Research Group.
They noted that the drug's use was recently suspended in Italy after two people died of health problems.
FDA spokeswoman Laura Bradbard said the agency regularly monitors "adverse events," including death, associated with drugs and will respond to the Public Citizen petition.
Worldwide, 8 million people have taken the drug, the FDA says.
In approving the drug in 1997, the FDA said it is "moderately effective" at helping patients lose weight. In studies, they lost about 7 to 11 more pounds than mere dieters.
The FDA also said that Meridia did not appear to pose the risk of heart valve damage that forced it to ban the popular diet drugs, Redux and fenfluramine, the "fen" in fen-phen.
At the time, the FDA cautioned that because of Meridia's side effects, no one with poorly controlled hypertension, heart disease or irregular heartbeat or who has survived a stroke should use the drug. And it said that it is only for the seriously obese, as measured by a body mass index - the relationship of weight to height - of 30 or greater. An example would be someone who is 5 feet, 6 inches and weighs 185 pounds.
Meridia works a little differently than fenfluramine and Redux. Those drugs fooled patients into feeling full by boosting production of a brain chemical called serotonin. Meridia, on the other hand, slows the body's dissipation of the serotonin it naturally produces.
Abbott spokeswoman Brotz said people taking the drug are already severely overweight, meaning they are likely to have other health problems that could be the cause of death.