Two drugs used to treat heart rhythm irregularities in more than 200,000 Americans increased the risk of heart attack and death in a major clinical trial, Federal health officials said today.
The Food and Drug Administration said it was immediately advising doctors to stop prescribing the drugs, Tambocor and Enkaid, for mild or moderate heart rhythm irregularities, or arrhythmias.
The National Heart, Lung and Blood Institute said that more than twice as many patients getting the drugs suffered heart attacks or death as those taking dummy pills, making it necessary to suspend a major part of the test three years early.
"Absolutely, unequivocally, this trial was a success because we have identified two drugs of a type that are more dangerous than the disease they are supposed to treat," Dr. Killip said in a telephone interview.
Scarce quality assurance documentation in major clinical trial registries for approved medicines used in post-marketing clinical trials
