14 seconds of research revealed this..
http://www.rense.com/general45/marine.htm
"Mefloquine, the drug used by the US military to protect against malaria, has in recent years been the subject of much speculation and scaremongering among American troops. It comes in tablet form and has to be taken once a week, starting a week before arriving in a malaria-risk area and continuing for four weeks after departing from the area. The majority of people who take mefloquine experience few, if any, side effects,
though the drug can sometimes induce nausea, dizziness and vivid dreams. A small minority of those who take it have reported serious side effects, including seizures, hallucinations and severe anxiety. According to the US Centers for Disease Control (CDC), such side effects are 'very rare'. Both the CDC and the World Health Organisation recommend mefloquine as the most effective treatment for those travelling to malaria-risk areas."