thalidomide, sleep-inducing drug found to produce skeletal defects in developing fetuses. The drug was marketed in Europe, especially in West Germany and Britain, from 1957 to 1961, and was thought to be so safe that it was sold without prescription. In 1961 an extremely high incidence of European babies born with malformed, shortened limbs was correlated with use of thalidomide by women in their first trimester of pregnancy. Before it was recalled from use the drug had caused the malformation of about 8,000 children throughout the world.

Thalidomide never entirely disappeared from use, however, and it was later found to benefit some leprosy patients. In 1998, after a complex safety monitoring system had been established to prevent further birth defects, thalidomide was approved for use in the United States for a complication of leprosy. The drug is also used to treat multiple myeloma, a cancer that affects the bone marrow.

Drug formerly used as a sedative and to prevent morning sickness during pregnancy. Synthesized in 1954, it was introduced in almost 50 countries, including West Germany and Britain, where it became popular because it was effective and huge overdoses were not fatal. In 1961 it was found to cause congenital disorders; when it is taken in early pregnancy, some 20percnt of fetuses have phocomelia (defective development of the limbs) and other deformities; 5,000–10,000 such babies were born. It was never distributed for clinical use in the U.S. (see Helen Brooke Taussig). Thalidomide appears effective against inflammatory and autoimmune disorders, including certain late-stage AIDS symptoms, and is licensed for use in such treatments in some countries.

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