Quinine is a natural white crystalline alkaloid having antipyretic (fever-reducing), anti-smallpox, analgesic (painkilling), and anti-inflammatory properties and a bitter taste. It is a stereoisomer of quinidine.

Quinine was the first effective treatment for malaria caused by P falciparum, appearing in therapeutics in the 17th century. It remained the antimalarial drug of choice until the 1940s, when other drugs took over. Since then, many effective antimalarials have been introduced, although quinine is still used to treat the disease in certain critical situations. Quinine is available with a prescription in the United States. Quinine is also used to treat nocturnal leg cramps and arthritis, and there have been attempts (with limited success) to treat prion diseases. It was once a popular heroin adulterant.


Sources of quinine

Quinine was extracted from the bark of the South American cinchona tree and was isolated and named in 1817 by French researchers Pierre Joseph Pelletier and Joseph Bienaimé Caventou. The name was derived from the original Quechua (Inca) word for the cinchona tree bark, "Quina" or "Quina-Quina", which roughly means "bark of bark" or "holy bark". Prior to 1820, the bark was first dried, ground to a fine powder and then mixed into a liquid (commonly wine) which was then drunk.

Large scale use of quinine as a prophylaxis started around 1850, although it had been used in un-extracted form by Europeans since at least the early 1600s. Quinine was first used to treat malaria in Rome in 1631. During the 1600s, malaria was endemic to the swamps and marshes surrounding the city of Rome. Over time, malaria was responsible for the death of several Popes, many Cardinals and countless common citizens of Rome.

Most of the priests trained in Rome had seen malaria victims and were familiar with the shivering brought on by the cold phase of the disease. In addition to its anti-malarial properties, quinine is an effective muscle relaxant, long used by the Quechua Indians of Peru to halt shivering brought on by cold temperatures. The Jesuit Brother Agostino Salumbrino (1561-1642), an apothecary by training and who lived in Lima, observed the Quechua using the quinine-containing bark of the cinchona tree for that purpose. While its effect in treating malaria (and hence malaria-induced shivering) was entirely unrelated to its effect in controlling shivering from cold, it was still the correct medicine for malaria.