Long term quinine for muscle cramps may increase death risk

Long term use of quinine, prescribed off label for muscle cramps or restless leg syndrome, is associated with increased mortality, says a study of UK GP prescribing published in JAMA.1

The British National Formulary (BNF) says that quinine salts such as quinine sulfate 200-300 mg at bedtime are effective in reducing nocturnal leg cramps by about 25%.2 Because of potential toxicity, however, quinine is not recommended for routine treatment and is advised only when cramps are very painful or frequent, …