History of antipyretic analgesic therapy.

The use of naturally occurring plant materials for the relief of pain dates back to 3,000 B.C., although rapid advances in antipyretic analgesic therapy have been made more recently. Salicylic acid was synthesized in 1860, and the pyrazolone group, first represented by antipyrine, in 1883. Phenacetin was developed in 1886. Acetaminophen has been in use since the 1890s.