The effects of aspirin-like substances have been known since the ancient Romans recorded the use of the willow bark as a fever fighter. The leaves and bark of the willow tree contain a substance called salicin, a naturally occurring compound similar to acetylsalicylic acid, the chemical name for aspirin.

Even as far back as 400 B.C. Hippocrates recommended a tea made from yellow leaves. It wasn't until the 1800's that scientists discovered what was in the willow tree that relieved pain and reduced fever. The substance was named salicylic acid. But when people suffering from pain took the salicylic acid, it caused sever stomach and mouth irritation.

In 1832, a thirty-seven-year-old French chemist named Charles Gergardt mixed another chemical with the acid and produced good results, but the procedure was difficult and took a lot of time. Gerhardt decided the new compound wasn't practial, so he set aside.

Sixty-five-years later a German chemist, Felix Hoffmann, was searching for something to relieve his father's arthritis. He studied Gerhardt's experiments and "rediscovered" acetylsalicylic acid--or aspirin, as we now know it.

Dr. Lawrence Craven, a California general practitioner, in 1948, notices that the 400 men he prescribed aspirin to hadn't suffered any heart attacks. He regularly recommends to all patients and colleagues that "an aspirin a day" could dramatically reduce the risk of heart attack.

In 1971 John Vane began his work on aspirin. Over a weekend he conceived the notion that the mysterious drug might work by inhibiting the generation of prostaglandins. He turned again to his bioassay system for the answer and within a few days he had convinced himself and his colleagues that this indeed was the missing mechanism of action.