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Sensitive to Quinine? Beware Tonic Water!

Tonic water contains quinine. Those who are sensitive to this drug must beware tonic water, as even small amounts could trigger serious reactions.

Quinine was once available both as a prescription drug and over the counter. Doctors would prescribe it to help people cope with nighttime leg cramps. For some people, however, quinine can trigger a serious or even deadly reaction. The FDA banned over-the-counter sale of quinine products in 1994. In late 2006, it announced that no quinine-containing drugs were to be manufactured, distributed or prescribed for any reason other than the treatment of malaria. The agency made it clear that the potential for serious or even lethal reactions outweighed any potential benefit of relief from leg cramps through quinine use. What the agency has not yet done, however, is require soft drink manufacturers to take the quinine out of tonic water. Should you beware tonic water?

Who Should Beware Tonic Water?

Q. Warning bells went off for me when I read your column about taking quinine for leg cramps. In 1983 my father was given quinidine for a heart arrhythmia. He started bleeding internally as a result of the drug. The bleeding was irreversible, and he died shortly afterwards.

I discussed it with my internist, and his first question to me was: “Do you drink any mixed drinks with tonic water?” The answer is no. I have also reminded my children about a possible reaction to quinine.

A. You are very wise to be wary of quinine in tonic or medicines. Some people are genetically predisposed to severe adverse reactions to the heart drug quinidine and its close cousin quinine.

Many years ago, a reader shared this frightening experience:

“One evening I drank 5 ounces of tonic water; the next morning I was in the emergency room with a frightening skin reaction. I was hospitalized for many days.

“My platelet count dropped to 1,000. Now it has gradually come back up to 266,000. I was diagnosed with ITP (idiopathic thrombocytopenic purpura), triggered by the quinine in the water. It nearly killed me.”

Side Effects of Quinine:

Many people find that drinking a few ounces of tonic water in the evening helps ward off midnight attacks of cramps. Keep in mind that, although the dose of quinine in tonic water is low, some people are sensitive even to small amounts of this compound.

Q. I’ve been drinking tonic water for leg cramps, but I developed severe pressure in the right side of my head and my temple. I was taking a few ounces of tonic water each night for leg cramps. Could this be causing the problem?

Is Quinine Causing a Terrible Headache?

A. The active ingredient in tonic water is quinine. This natural compound gives tonic its distinctive bitter taste.

Quinine was once prescribed for nighttime leg cramps, but the FDA no longer permits that use because of serious side effects. Although rare, a blood disorder called idiopathic thrombocytopenic purpura (ITP) can be lethal.

Some people are very sensitive to the other possible adverse effects of quinine, which include headache, ringing in the ears, anxiety, confusion, visual disturbances, skin rash and fatigue. Perhaps your evening beverage is causing your terrible headache and you should beware tonic water.

Iris in Seattle reminds us:

“The quinine in tonic water also is enough to cause heart arrhythmia for those who are sensitive, i.e. me. I love the taste of it but had to quit drinking it long ago.”

Other Ways to Prevent Leg Cramps:

We are sending you our Guide to Leg Pain with other remedies for nighttime leg cramps including pickle juice, yellow mustard, soap under the sheet and stretches before bedtime. All of these are well worth a try, and we don’t believe any of them will cause a terrible headache or have other potentially dangerous side effects.

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About the Author
Terry Graedon, PhD, is a medical anthropologist and co-host of The People’s Pharmacy radio show, co-author of The People’s Pharmacy syndicated newspaper columns and numerous books, and co-founder of The People’s Pharmacy website. Terry taught in the Duke University School of Nursing and was an adjunct assistant professor in the Department of Anthropology. She is a Fellow of the Society of Applied Anthropology. Terry is one of the country's leading authorities on the science behind folk remedies..
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