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Tonic water is a soft drink containing quinine, which gives it a bitter taste. Quinine is a common treatment for malaria. Some people believe that it can also help with leg cramps and restless legs syndrome.
Quinine comes from the bark of the cinchona tree. This tree is native to central and South America, as well as some islands in the Caribbean and western parts of Africa.
People have consumed quinine in tonic water to help treat cases of malaria for centuries.
In this article, learn about what quinine is and what its side effects and possible benefits are.
Doctors continue to use quinine as a part of malaria treatment. However, research suggests that newer treatments may eventually replace quinine as a malaria treatment due to quinine’s adverse effects at therapeutic doses.
Researchers cite the poor tolerability of the drug and difficulties complying with complex dosing routines as reasons to be concerned about regular medicinal use.
As a food additive, quinine offers a bitter taste. Manufacturers usually add it to tonic water.
Some people use tonic water to help treat nighttime leg cramps, but there is little evidence to suggest that this is effective.
Experts consider quinine safe to consume in small doses. The United States Food and Drug Administration (FDA) have approved up to 83 parts per million in carbonated beverages.
The FDA also specify that manufacturers must place quinine on the label for consumers to easily see.
Some people may experience allergic reactions to quinine. If this is the case, a person should avoid tonic water and any other products that contain quinine.
People who should avoid quinine in medications include:
- women who are pregnant or breastfeeding
- those with abnormal heart rhythms
- those with liver or kidney disease
- those with low blood sugar
Some medications can interact with quinine. These include:
- blood thinners
- neuromuscular-blocking drugs
- seizure medication
The amount of quinine in tonic water is not likely to interact with a person’s medication or cause issues for people with the medical conditions listed above. However, people with these risk factors should not take quinine supplements or medications unless a doctor prescribes it.
Many people believe that drinking tonic water helps with nighttime leg cramps and restless legs syndrome. However, there is no scientific evidence verifying this belief.
In fact, the FDA have warned doctors against prescribing quinine to treat leg cramps or restless legs syndrome.
Tonic water is a carbonated soft drink that may contain sugar and has little nutritional value. The quinine present in tonic water provides a distinctive bitter flavor. While not dangerous, tonic water does not have any benefits and could lead to an unnecessary increase in calorie consumption.
Quinine is very diluted in tonic water. The likelihood of a person experiencing any side effects from drinking tonic water is slim. However, side effects of quinine can include:
- ringing in the ears
- stomach cramps
As a medication, quinine may have more severe side effects. Some of the possible side effects of taking quinine as a medication include:
- abnormal heartbeat
- kidney damage
- severe allergic reaction
- electrolyte imbalance
- vision or eye issues
- problems with bleeding
- thrombocytopenia (decreased blood platelets)
- lung toxicity
People who regularly drink tonic water may also want to consider the extra sugar and calories that they are consuming. Soft drinks, including tonic water, have little nutritional value but contribute to a person’s daily calorie intake.
The quinine in tonic water helps give it a bitter taste. People should not mistake tonic water for a healthful drink, as it may contain sugar and provides no additional nutritional value.
Tonic water cannot help a person with leg cramps or restless legs syndrome. The quinine in tonic water is very diluted.
It is unlikely that a person will experience even mild side effects from drinking tonic water, but they should be cautious if they are taking quinine as a medication and try to report any side effects to a doctor.