Abstract
1 Major adverse reactions to mild analgesics, unless these drugs are abused or taken in high doses, are believed to be rare. 2 However, because of the massive and universal use of these drugs, quantitative measurement of the risk involved is imperative. At present, contradictory regulatory decisions about the use of mild analgesics are based on circumstantial evidence. 3 It is only by the conduct of epidemiological studies that data leading to decisions based on scientifically sound judgments may be obtained.