Compound analgesics are those with multiple active ingredients; they include many of the stronger prescription analgesics.
Active ingredients that have been commonly used in compound analgesics include:
Several such formulations have disappeared from over-the-counter status in drug store aisles and other retail outlets. One example is APC (aspirin, phenacetin, and caffeine) compound tablets common from the 1940s to 1983; because of harmful side effects of phenacetin, Anacin in the U.S. was reformulated to eliminate it; while Vincent's APC is no longer sold. Some others have been judged to contribute too often to substance abuse.
Another example is Bex, a once popular Australian compound analgesic which is no longer sold. It contained 42% aspirin, 42% phenacetin, plus caffeine.
The United States Food and Drug Administration also now requires that manufacturers of compound analgesics unequivocally state each ingredient's purpose.