The quinolone family of antibiotics grew out of research on anti-malarial drugs, which also carry a heavy load of side effects. One member of that family, a malaria medication called mefloquine (Larium), has become notorious for causing problems that include, according to FDA, "psychiatric symptoms ranging from anxiety, paranoia and depression to hallucinations and psychotic behavior. On occasions, these symptoms have been reported to continue long after mefloquine has been stopped."