First off malaria medication is taken orally in the form of a pill. Mefloquine is the drug of choice these days as it is the only medication at least partially effective against all forms of the disease. It is not 100% effective against any of them. I know from experience as two of my friends contracted malaria while on the drug when we were in the Congo peace keeping 2 years ago. Not everybody can take mefloquine. You must have a blood test done called a G6-PD prior to going on the medication. A small percentage of the population does not have a certain enzime in the blood which precludes the use of mefloquine. Meflouquine is taken once a week, other drugs must be taken daily. You go on it two weeks prior to exposure and stay on it three weeks after your return. Your Dr. can best advise on the requirement to take the drugs. Some of the side effects include loss of sleep (me for sure) and heightened sexual dreams, unfortunatly not me.