Their study had found a higher death rate among patients receiving a new anti arrhythmic drug than among those receiving a placebo.

Principles of evidence based medicine have transformed the way we look at clinical interventions and may prevent repetitions of public health disasters such as the inappropriate promotion of hormone replacement therapy and anti arrhythmic drugs.

They were prescribed very widely because heart attacks are a very common thing, and it took so long for us to find out that these drugs also caused an increased rate of death that before we detected that safety signal, over 100,000 people died unnecessarily in America from the prescription of anti arrhythmic drugs.

So in 1980, some researchers did a study on a drug called lorcainide, and this was an anti arrhythmic drug, a drug that suppresses abnormal heart rhythms, and the idea was, after people have had a heart attack, they're quite likely to have abnormal heart rhythms, so if we give them a drug that suppresses abnormal heart rhythms, this will increase the chances of them surviving.