Leonard Colebrook (born March 2, 1883, Guildford, Surrey, Eng.—died Sept. 29, 1967, Farnham Common, Buckinghamshire) was an English medical researcher who introduced the use of Prontosil, the first sulfonamide drug, as a cure for puerperal, or childbed, fever, a condition resulting from infection after childbirth or abortion.
Colebrook joined researcher Almroth Wright in 1907 at St. Mary’s Hospital. In 1926 Colebrook became interested in the incidence of puerperal fever in women who had just undergone childbirth. Nine years later, he obtained the newly discovered antibacterial drug Prontosil and used it to treat a woman who was dying of puerperal fever. The patient recovered, and the drug was next used successfully on a woman dying of septicemia (blood poisoning). By 1945, as a result of the widespread use of the drug, puerperal fever was no longer a common problem. Prontosil was also used to treat other diseases, including lobar pneumonia.
At the outbreak of World War II, Colebrook went to France to investigate the treatment of burns. He established the efficacy of the sulfonamides and then of penicillin in controlling the infection of burns, urged the wider application of skin-grafting techniques to heal burns, and brought the problem of tissue rejection to the attention of Peter B. Medawar. Colebrook served as director of the Burns Investigation Unit of the Medical Research Council from 1942 to 1948.