what is quinine in tonic water

Quinine is a bitter-tasting compound that is found in tonic water. It is extracted from the bark of the cinchona tree, which is native to central and South America, as well as some islands in the Caribbean and western parts of Africa. Quinine has been used for centuries to treat malaria, and it is still used for this purpose in tropical regions. In the United States, the FDA allows tonic water to contain no more than 83 parts per million of quinine. This is because there can be side effects from quinine, such as nausea, stomach cramps, diarrhea, vomiting, ringing in the ears, confusion, and nervousness. However, when found in small doses in tonic water, quinine is considered safe to consume. Some people believe that drinking tonic water can help with leg cramps and restless legs syndrome, but there is little evidence to support this claim.