Abstract The concept that healers could accidentally produce medical disorders in the course of diagnosing or treating their patients was recognized as early as 1700 B.C. Nonetheless, the term iatrogenic (from Greek: iatros = healer; genic = origin) was not used until the early twentieth century. By the 1970s, its meaning had been expanded considerably, so that it encompassed any type of adverse event experienced by any patient, caused by any health care provider, via either commission or omission.