The bark of the cinchona tree contains quinine, formerly the primary medication for the treatment of malaria, a serious mosquito-borne disease prevalent in tropical and subtropical countries. The Centers for Disease Control and Prevention estimates that as many as 1,003,000 people worldwide died of the disease in 2008 alone, most of them young children. As certain strains of malaria develop resistance to the synthetic drugs that replaced quinine, cinchona bark is beginning to re-emerge as the treatment of choice in some parts of the world. Consult your doctor before taking cinchona bark.
Features
The cinchona tree -- botanically known as Cinchona succirubra and Cinchona officinalis and also known as fever tree and Jesuit's bark -- is a tropical evergreen native to mountainous areas of Central and South America and also cultivated in Africa and Asia. According to legend, the tree was named for the Countess of Chincon, a Peruvian viceroy's wife who was reputedly cured from a fever by the bark in 1638. The dried ground bark, often distributed by Jesuit priests, was used in 17th and 18th century Europe to treat malaria and other infections; in the mid-19th century, the British began cultivating the cinchona tree. In addition to its use in treating malaria, quinine may also be advised by herbalists to treat digestive disorders, arthritis, and vascular problems. The bitter alkaloids are also used to flavor tonic water; most brands contain about 15 mg of quinine per bottle. Research is ongoing concerning quinine's use with antibiotics to treat resistant forms of malaria.
Constituents and Effects
Cinchona bark contains 16 percent quinone alkaloids, primarily quinine, quinidine, cinchonine, and cinchonidine. Quinine is the most pharmacologically active of the compounds. Drugs.com -- which provides peer-reviewed medical information to consumers -- reports that quinine is active against Plasmodium falciparum, the pathogen that causes malaria, and adds that the compound may also have the ability to enhance the immune system. Quinidine derived from cinchona bark inhibits contractability of the heart, and is used to treat cardiac arrhythmia. Applied Health notes that cinchona bark works by influencing cellular enzymatic processes, leading to lowering of nucleoprotein metabolism and the death of microorganisms. In addition to its antimicrobial qualities, quinine has astringent, antispasmodic, and carminative -- or gas-reducing -- qualities. Quinine is approved by the herbal regulatory agency German Commission E to treat bloating and loss of appetite.
Research
In a clinical study published in 2000 in "Antimicrobial Agents and Chemotherapy," patients with multi-drug resistant Plasmodium falciparum malaria were treated with a combination of clindamycin and quinine; researchers found that this combination was more effective than both quinine alone and quinine in conjunction with tetracycline. They noted that the regimen was a safe and effective treatment for drug-resistant malaria, and could be particularly valuable in treating children and pregnant women, who should not receive tetracycline.
Usage and Considerations
Cinchona bark is usually taken at dosages of 1 g a day; quinine is used at doses of 325 mg to 1 g a day when it is refined as a sulfate salt. Patients taking cinchona bark must be monitored for quinine toxicity. A condition called cinchonism develops in people who are hypersensitive to cinchona bark alkaloids; symptoms include severe headache, stomach cramps, convulsions, blindness, paralysis and collapse. Large doses of quinine have a depressant effect on the heart, with Drugs.com reporting that dosages of 2 g to 8 g can be fatal to an adult. Quinine can interact with prescription drugs. Consult your doctor before using quinine; don't use it if you are pregnant or breast feeding.
References
- Drugs.com: Complete Quinine Information
- University of Minnesota; James Ford Bell Library: Cinchona; Juliet Burba; 2011
- Applied Health: Cinchona
- "Antimicrobial Agents and Chemotherapy"; Therapeutic Responses to Quinine and Clindamycin in Multi-Drug Resistant Falciparum Malaria; Sasithon Pukrittayakamee et al.; September 2000
- Centers for Disease Control and Prevention; Cinchona; Staff; February 2010
