Mefloquine in the geographic region visited. It is typically taken for one to two weeks before entering an area with malaria. Doxycycline and atovaquone/proguanil provide protection within one to two days and may be better tolerated. If a person becomes ill with malaria despite prophylaxis with mefloquine, the use of halofantrine and quinine for treatment may be ineffective. Mefloquine is used as a treatment for chloroquine-sensitive or resistant "Plasmodium falciparum" malaria, and is deemed a reasonable alternative for uncomplicated chloroquine-resistant "Plasmodium vivax" malaria. It is one of several drugs recommended by the United States' Centers for Disease Control and Prevention. It
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