a glass of tonic water with a slice of lemon

The Food and Drug Administration has banned the use of quinine to treat leg cramps. Although this drug has been available for centuries, the FDA has determined that it is far too dangerous to use for anything but malaria.

Quinine Dangers

The trouble is that some people are extremely sensitive to quinine’s toxic effects. This drug can cause headache, rash, ringing in the ears, nausea, dizziness and blurred vision.

The most serious reactions are rare but can be life threatening. Blood disorders can lead to hemorrhaging. Dozens of hospitalizations and two deaths are linked to quinine.

What about Tonic Water?

Clearly, quinine can be dangerous for certain people, but the FDA has not banned quinine from tonic water. Quinine gives this beverage its distinctive flavor. Either the FDA doesn’t consider tonic water a danger to public health or the agency worries about arousing the ire of millions of gin and tonic drinkers.

Because of this loophole, many people have discovered that drinking tonic water can help prevent muscle cramps. One reader related her experience:

“I suffered with nightly leg cramps until one magic day on the Greek island Santorini. I had gone on tour as a guest singer of the New York Choral Society. One free afternoon, a group of us went to a black sand beach where I swam. The only other member of the group who also swam was a New York trauma surgeon. I developed a cramp and was trying to walk it out when he told me about Schweppes tonic, which contains a very small amount of quinine.

“I couldn’t find any tonic on Santorini or in Athens, but as soon as I returned home I started drinking a large glass (diet, with cranberry) every night. It has worked for me for several years, but I definitely know if I skip a dose!

“I asked a pharmacist friend to search the literature to see if anything else contains a small amount of quinine. She couldn’t find anything and told me the dangers of using high-dose quinine. I have checked with my doctors and have heard nothing against my practice of drinking Schweppes.”

Tonic contains 83 mg. of quinine in a liter. An eight-ounce glass or tonic would only have about 20 mg of quinine, considerably less than the dose that used to be prescribed for leg cramps (200 to 300 mg).

Tonic Water Works for Muscle Cramps

Despite the low dose, however, many readers maintain that it works:

“My doctor recommended tonic water for nocturnal leg cramps. It works every time very quickly. In less than five minutes I get relief and can go back to sleep. I suffer NO pains if I drink half a glass before I go to bed.”

Even Tonic Water Has Some Hazards

Some people find even the small amount of quinine in tonic water can pose problems. These folks may experience ringing in the ears, rash, itching or blurred vision and should steer clear of tonic water altogether.

There are those who are so sensitive that even a little bit of quinine could prove life threatening.

“Quinine in tonic water proved almost fatal for me. Nighttime leg cramps have been an ongoing problem, so I bought a bottle of tonic water.

“On Saturday I had a 5-ounce glass before supper. Sunday morning by 9 am I was in the emergency room with a frightening skin reaction. I was hospitalized for many days and diagnosed with a dangerous blood disorder called idiopathic thrombocytopenic purpura (ITP). My hematologist said it was triggered by the quinine water.”

We have also heard from people who developed tinnitus after drinking tonic:

“I have just developed a hissing sound in my ears. The onset was very rapid! The doctor diagnosed it as tinnitus, but would give me no reason for the problem. He said there wasn’t anything I could do. I’ve noticed some days it is less disturbing than others but some nights it awakens me because it has become so loud.

“I was drinking large quantities of tonic water, which contains quinine, when this started. Do you have any suggestions to help me?”

The quinine in tonic is the likely culprit. Ringing or hissing in the ears can be a complication of quinine. Tonic water should be discontinued completely.

For such people, home remedies may be the best way to get relief from nocturnal leg cramps. Our Guide to Leg Pain has instructions on stretching as well as a range of remedies.

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  1. Arnold

    Cramps could be an indication of Magnesium deficiency. Try Mg tablets instead of Tonic, might be a healthier option.
    If you have Tinnitus, it is likely to be associated with lack of Oxygen.
    Try to breathe heavily for a few minutes and watch your Tinnitus disappear. Worked for me many times.

  2. james

    I started using tonic water as a biting insect repellant a week ago. As zika virus has been reported in Maryland, I am looking for my edge and so far, no bites. I have had no adverse reaction to drinking ten ounces of tonic before walking.

  3. gipsy

    been having leg cramps at night for amonth and a half . dr. told me to drink tonic water i thought he was crazy.i bought it, tried it,leg cramp free all night.

  4. Herby
    South Africa.

    I drink Instant Chicory Drink daily , the ingredients are as follows , Corn syrup solids , chicory extracts ,caramel and Quinine . Is it safe ??.
    I haven`t experienced any side effects .I feel great .
    Each 100mg servings contains 30kj energy , 0g sugar , 0g fat , 0g saturates and 0.1g of salt .
    Could this be dangerous ?
    Herby Albert

  5. Rebecca

    My husband has advanced bladder cancer. He sometime loses a bit of blood in his urine. His doctors want him to drink lots of liquids. Recently,he started asking for tonic water with lime and ice. I was happy to see him drinking and refilled his glass any time he asked. After a few glasses, there was a dramatic increase in the bleeding from his bladder. He developed clots with urinary blockage and received treatment in an emergency room. I just happened to read somewhere that quinine interferes with platelet function and can contribute to bleeding. This must be the case, because when he stopped drinking the tonic water,the bleeding slowed and his urine returned to near normal.

  6. brian

    Add your thoughts to the conversation. what is the side effect of drinking club tonic water or quinine tonic.

  7. Jim

    Jim: To certain people quinine is a deadly poison! It should NEVER be included in any food or food product of any type without CLEAR warning that quinine is present!!

    My wife’s last encounter with it (June 6,2016) nearly killed her: Emergency Room personnel did not think she would survive! The source of the quinine was either a bowl of soup or a cup of fountain coke, her meal 45 to 60 minutes before admission to the emergency room.

    The effect of the quinine was more than half an hour of violent vomiting.

  8. James

    I suffered from leg cramps due to type 2 diabetes. I only drank tonic water as an alternative drink and did not know until I read this article on quinine that it helps with leg cramps. Looking back, my leg cramps would ease off and stop for periods of time when I bought tonic water. They should advertise this on the table. Their sales would go through the roof ?

  9. Deborah
    Margate Florida

    I live in Florida and I drink tonic water and lemon all the time to help cool down on very hot days. Could this be dangerous?

  10. B
    U. K

    Tonic water has been and is a great remedy for my nighttime leg cramps.
    I drink about 3 fluid ounces before bed and have no side effects. It’s a great relief!

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