Quinine may be familiar to you if you drink gin and tonic or perhaps vodka and tonic. This is because quinine is in the tonic and gives it that bitter taste. It is a white powder that is obtained from the bark of the cinchona tree that is found in the Andes mountain range of Ecuador and Peru. They were probably discovered by Peruvian Jesuits, who introduced quinine into Europe around 1640. However the destruction of these trees to obtain quinine made them rare and so a way of making it synthetically was sought. This was found in 1944 by Robert Woodward and William Doering by synthesising quinine from coal tar. Quinine’s formula is C₂₀H₂₄N₂O₂. click to view 3D structure.

Tonic water is not its only use though; it has use in medicine for it is the traditional treatment for muscle cramps. The reason for muscle cramps is not very well known yet but they are very common and quinine can reduce the frequency of muscle cramps for those who suffer on a weekly or even daily basis. The way in which quinine helps to reduce frequency and severity of cramps is not known either and there have been studies to try and assess the efficacy of the drug.

Malaria has been around ever since records began about 6000 years ago. Malaria is caused by a parasite plasmodium vivax, which is carried by mosquitoes in tropical climates. It causes severe fevers that go through cycles of 48 to 72 hours, passing through hot and cold phases. In 1957 the countries of the world set forth to eradicate the malarial parasite from the Earth. In 1974 it failed after there was a realisation that the parasite was too widespread and integrated into the human system. It did help to improve public malaria awareness though and efforts are used to control the disease rather than to eradicate it. Quinine is excellent at reducing fevers and so it became the first and only, until the synthesis of other drugs, anti-malarial drug brought to Europe by the Jesuits. However these new synthesised drugs were preferred to the bark of the cinchona tree. New drugs included Chloroquine and Mefloquine (Larium). Mefloquine caused serious side effects and the parasite started to gain resistance to these drugs. This has led to renewed interest into quinine for an anti-malarial drug.

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