Is Quinine in Tonic Water Safe?
The pros and cons of quinine make tonic water a challenging choice for many people in their fight against leg cramps. What else works for muscle cramps?
Quinine is bitter. It gives tonic water a distinctive flavor. Not that long ago you could buy quinine pills over the counter in most pharmacies under brand names like Legatrin, Quinamm and Q-vel. But the Food and Drug Administration banned the use of OTC quinine to treat leg cramps in 1994. Although this drug has been available for centuries, the FDA has determined that it is far too dangerous to use for anything but malaria.
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 the drug.
The FDA ordered drug companies to stop selling quinine for anything but malaria in 2007. Only one product was allowed. Qualaquin can be prescribed by physicians but the cost is high. One pill of Qualaquin could cost over $6. That could make sense for a drug to treat malaria, which is rare in the US. Muscle cramps are anything but rare.
Any physician who prescribes Qualaquin for leg cramps could risk the wrath of the FDA. On July 8, 2010, the agency issued the following warning.
What is the regulatory history of quinine? What are the approved indications for quinine, and what are its common off-label uses?
Dr. Shamsuddin: Quinine was approved by the FDA for the treatment of uncomplicated Plasmodium falciparum malaria in August 2005. Before that date, quinine was marketed in the United States as an unapproved product. On December 12, 2006, the FDA ordered unapproved quinine drug products to be removed from the market and cautioned consumers about the off-label use of quinine to treat leg cramps.
The approved indication is for the treatment of uncomplicated malaria caused by P falciparum. However, a common off-label use is for the treatment of leg cramps. As reported from office-based physician practices in the United States, approximately 92% of quinine use is associated with the off-label indication relating to the treatment of leg cramps and muscle pain.
What are some of the safety concerns with quinine?
Dr. Shamsuddin: Quinine is derived from cinchona bark. Cinchonism is the most common adverse event associated with quinine use; symptoms of cinchonism may include nausea, headaches, flushing, and tinnitus. However, serious adverse reactions have also been associated with the use of this product, and these are included in the Warnings and Precautions section of the product labeling. These mainly include hematologic events, primarily thrombocytopenia, but also ventricular arrhythmias, hypersensitivity reactions, and optic neuritis.
Any concluding comments for our members?
Dr. Shamsuddin: The overall message is that with the use of a drug for the treatment of any condition, prescribers have to assess the risk and benefits of that drug. At this time, we don’t think that the risk/benefit assessment for quinine in the treatment of leg cramps is favorable. Prescribers and users should be aware that there are serious adverse events associated with its use.