• Serious and life-threatening hematologic reactions, including thrombocytopenia and hemolytic uremic syndrome/thrombotic thrombocytopenic purpura (HUS/TTP), may occur if quinine is used for treatment or prevention of nocturnal leg cramps†.
• Chronic renal impairment associated with TTP reported.

• Known risks associated with use of quinine, in the absence of evidence of safety and efficacy of the drug for treatment or prevention of nocturnal leg cramps†, outweigh any potential benefits for this unlabeled indication.

  (See Use for Treatment or Prevention of Nocturnal Leg Cramps under Cautions.)

REMS:

FDA approved a REMS for quinine sulfate to ensure that the benefits of a drug outweigh the risks. The REMS may apply to one or more preparations of quinine sulfate and consists of the following: medication guide and communication plan. See the FDA REMS page ([Web]) or the ASHP REMS Resource Center ([Web]).