Quinine is a bitter compound that comes from the bark of the cinchona tree. The tree is most commonly found in South America, Central America, the islands of the Caribbean, and parts of the western coast of Africa. Quinine was originally developed as a medicine to fight malaria. It was crucial in reducing the death rate of workers building the Panama Canal in the early 20th century.
Quinine, when found in small doses in tonic water, is safe to consume. The first tonic waters contained powdered quinine, sugar, and soda water. Tonic water has since become a common mixer with liquor, the most well-known combination being gin and tonic. The U.S. Food and Drug Administration (FDA) allows tonic water to contain no more than 83 parts per million of quinine, because there can be side effects from quinine.
Today, people sometimes drink tonic water to treat nighttime leg cramps associated with circulatory or nervous system problems. However, this treatment is not recommended. Quinine is still given in in small doses to treat malaria in tropical regions.
Quinine’s primary benefit is for the treatment of malaria. It’s not used to prevent malaria, but rather to kill the organism responsible for the disease. When used to treat malaria, quinine is given in a pill form.
Quinine is still in tonic water, which is consumed around the world as a popular mixer with spirits, such as gin and vodka. It’s a bitter beverage, though some manufacturers have tried to soften the taste a little with added sugars and other flavors.
Quinine in tonic water is diluted enough that serious side effects are unlikely. If you do have a reaction, it may include:
- stomach cramps
- ringing in the ears
However, these are more common side effects for quinine taken as a medication. Among the most serious potential side effects associated with quinine are:
- bleeding problems
- kidney damage
- abnormal heartbeat
- severe allergic reaction
Keep in mind that these reactions are primarily linked to quinine, the medication. You would have to drink about two liters of tonic water a day to consume a day’s dose of quinine in pill form.