Mefloquine the drug's very long half-life, the Centers for Disease Control originally recommended a mefloquine dosage of 250 mg every two weeks; however, this caused an unacceptably high malaria rate in the Peace Corps volunteers who participated in the approval study, so the drug regimen was switched to once a week. The first randomized, controlled trial on a mixed population was performed in 2001. Prophylaxis with mefloquine was compared to prophylaxis with atovaquone-proguanil. Roughly 67% of participants in the mefloquine arm reported greater than or equal to one adverse event, vs 71% in the atovaquone-proguanil arm. In the mefloquine arm, 5%
Mefloquine clearance is through the liver, and the primary means of excretion is through the bile and feces, as opposed to only 4% to 9% excreted through the urine. During long-term use, the plasma half-life remains unchanged. Liver function tests should be performed during long-term administration of mefloquine. Alcohol use should be avoided during treatment with mefloquine. Mefloquine is a chiral molecule with two asymmetric carbon centres, which means it has four different stereoisomers. The drug is currently manufactured and sold as a racemate of the ("R","S")- and ("S","R")-enantiomers by Hoffman-LaRoche, a Swiss pharmaceutical company. Essentially, it is two drugs in