Serious risks associated with using Quinine to prevent or treat nocturnal leg cramps

Quinine is FDA-approved for the label indications relating to leg ceived a dispensed prescription treatment of uncomplicated cramps and muscle pain.1 for quinine from U.S. outpatient Plasmodium falciparum malaria. Since 2006, there have been a retail pharmacies. In contrast, an It is not considered safe and ef- number of efforts to educate estimated 206,000 patients re- fective for the treatment or healthcare professionals about ceived a dispensed prescription prevention of leg cramps-- an these serious risks. These efforts for quinine in 2008.2 Cumula- "off-label" (non-FDA-approved) include labeling changes, adding tively from 2008 to 2011, use. Quinine is associated with general practice/family medi- serious and life-threatening ad- cine/doctor of osteopathy verse events, including specialties and internal medicine  thrombocytopenia, specialties prescribed the major-  hypersensitivity reac- ity of dispensed prescriptions for 3 tions, and quinine. Although use has de-  QT prolongation. clined, the FDA remains concerned because the majority Thrombocytopenia associated of quinine use is associated with with the use of quinine for the off-label indications relating to treatment or prevention of leg leg cramps and muscle pain, and cramps includes serious adverse events continue  immune thrombocyto- a boxed warning regarding he- to be reported. penic purpura matologic events associated with  hemolytic uremic syn- off-label use of quinine, and The agency will continue to drome FDA and pharmaceutical indus- monitor quinine use and remind  thrombotic thrombocyto- try communications. healthcare professionals about penic purpura with the serious risks associated with associated renal insuffi- Despite these efforts, awareness quinine in the preven- ciency. among prescribers regarding the tion/treatment of nocturnal leg approved indication for quinine cramps. Fatalities and renal insufficiency and the adverse events associated requiring hemodialysis have with its use for the treat- — Janelle Derbis been reported. ment/prevention of leg cramps continues to be concerning. Janelle Derbis, PharmD, is a member of the Health Professional Liaison Pro- Drug use data from office-based gram in the FDA Office of Special physician practices in the U.S., Drug Use Health Issues. indicate that approximately There has been a dramatic de- ninety-two percent of quinine cline in the use of quinine over the past several years. In 2011, use is associated with the off- 2 IMS Health, Vector One®: Total Pa- an estimated 51,800 patients re- tient Tracker. Years 2008-2011. Data extracted July 2012. 1 Encuity Resarch, Physician Drug and 3 IMS Health, Vector One®: National. Diagnosis Audit™. Years 2008-2011. Years 2008-2011. Data extracted July Data extracted July 2012. 2012.

FDA News for Health Professionals / U.S. Food and Drug Administration September 2012