CHLOROQUINE PHOSPHATE is an antiparasitic and anti-inflammatory drug used in the prophylactic treatment of malaria and for amelioration of the symptoms of rheumatoid arthritis and lupus erythematosus. Side effects are generally mild and transitory, although visual disturbance, muscle weakness, and acute psychotic behavior have been encountered. Sudden death due to chloroquine overdosage is uncommon. Thirteen fatal cases, involving 12 persons stationed in the Far East and one arthritic patient in this country, have been submitted to the Forensic Pathology Branch, indicating a new problem in the field of suicide. Report of Cases Case 1.— A 30-year-old American sailor was found dead in his home on Guam. Numerous bottles were present indicating heavy drinking prior to death. Suicide notes were found. Several personal survival kits which he had accumulated as an air crew member were found in the bedroom; 36 chloroquine phosphate tablets were missing from the kits. Case 2.— A