Plasmodium vivax the first-line treatment for "P. falciparum" malaria, it may also be used for P. vivax malaria in combination with primaquine for radical cure. An exception is artesunate plus sulfadoxine-pyrimethamine (AS+SP), which is not effective against P. vivax in many places. Mefloquine is a good alternative and in some countries is more readily available. Atovaquone-proguanil is an effective alternative in patients unable to tolerate chloroquine. Quinine may be used to treat "vivax" malaria but is associated with inferior outcomes. 32–100% of patients will relapse following successful treatment of "P. vivax" infection if a radical cure (eradication of liver stages) is not
Mefloquine events, about 11-17% of travelers are incapacitated to some degree. Mefloquine may cause abnormalities with heart rhythms that are visible on electrocardiograms. Combining mefloquine with other drugs that cause similar effects, such as quinine or quinidine, can increase these effects. Combining mefloquine with halofantrine can cause significant increases in QTc intervals. Mefloquine is contraindicated in those with a previous history of seizures or a recent history of psychiatric disorders. Women should not become pregnant and should use effective birth control while taking mefloquine. A retrospective analysis of outcomes in more than 2,500 women found no evidence that mefloquine was associated