Aspirin for AIDS? A ludicrous notion, perhaps, but aspirin is the prince of panaceas, the universal drug for everything from arthritis to colds, cramps and whiplash; from hangovers to headaches, other pains and rheumatic fever. Not to mention flu, charley horses and sprains. What's more, aspirin has lately proved useful in guarding against the complications of cataracts, diabetes and coronary heart disease. Some research indicates it even has the potential to help the body fight cancer. So why not AIDS?

That serious researchers at one medical center entertain such possibilities is a tribute to the seemingly limitless potential of the world's oldest cure-all -- acetylsalicylic acid. Americans consume more than 80 million aspirin tablets a day -- enough to cure about 15 billion headaches a year. . . .

First marketed in Germany in 1899, aspirin is a relatively safe painkiller, far less dangerous than such narcotics as codeine and morphine. But any effective drug is obviously potent, and all the more so when, like aspirin, it is freely available and easily abused. Harmless as it may seem, aspirin can kill: an overdose as small as 10 grams -- about 30 regular-strength aspirin tablets -- can be fatal in adults, and few medicine-chest menaces are worse than yummy "children's aspirin" disguised as candy. . . .

The drug's multifaceted nature has been described in literally thousands of studies, yet some of its mechanisms remain unclear. "It's frustrating," says Roger Maickel, professor of pharmacology and toxicology at Purdue University. Aspirin's chemical structure is simple, but aspirin raises many complex questions, and we just don't know the answers.