Quinine side effects include deafness, low blood platelets, and an irregular heartbeat. Use can make one more prone to sunburn. While it is unclear if use during pregnancy causes harm to the baby, use to treat malaria during pregnancy is still recommended. Quinine is an alkaloid, a naturally occurring chemical compound. How it works as a medicine is not entirely clear. Quinine was first isolated in 1820 from the bark of a cinchona tree. Bark extracts have been used to treat malaria since at least 1632. It is on the World Health Organization's List of Essential Medicines, the most effective and
History of malaria and make them more susceptible to other diseases. Spanish missionaries found that fever was treated by Amerindians near Loxa (Peru) with powder from Peruvian bark (later established to be from any of several trees of genus "Cinchona"). It was used by the Quechua Indians of Peru to reduce the shaking effects caused by severe chills. Jesuit Brother Agostino Salumbrino (1561–1642), who lived in Lima and was an apothecary by training, observed the Quechua using the bark of the cinchona tree for that purpose. While its effect in treating malaria (and hence malaria-induced shivering) was unrelated to its effect in controlling