A new study, which appears in the Feb. 18 issue of Circulation, also found the benefits were apparent within hours of giving clopiodgrel and those benefits continued for as long as a year when people took it daily after being discharged from the hospital.
The study included 12,562 people in hospital emergency departments in 28 countries. Their average age was 64, and 38 percent of them were women. The people in the study had either unstable angina or small heart attacks.
All of the people were treated with aspirin and either clopidogrel or placebo. The people in the clopidogrel group received a dose of 300 milligrams when they arrived at the hospital and then 75 milligrams each day for a year.
Within the first 30 days, 4.3 percent of the people in the clopidogrel group and 5.4 percent of the people in the placebo group had a heart attack, stroke or death. That means that clopidogrel users had a 21 percent reduction in major events.
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