DEFINITION: Blackwater fever is a clinical entity characterized by acute intravascular hemolysis classically occuring after the re-introduction of quinine in long-term residents in Plasmodium falciparum endemic areas and repeatedly using the product. CLINICAL PROFILE: The symptomatology appears brutally with emission of porto-colored urine, icterus, pallor, nausea, fever and acute renal failure. The hemolytic-like anemia is immediately severe. Parasitemia is mild or absent. The mechanism of renal failure is tubular necrosis. QUININE AND SIMILAR MOLECULES: Well known at the start of the 20th century, blackwater fever has become exceptional since 1950, when quinine was replaced by chloroquine. The disease reappeared in 1990, following the re-utilization of quinine because of resistance to chloroquine. Thereafter, several cases have been described with halofantrine and mefloquine, two new molecules similar to quinine (amino-alcohol family). The physiopathogenesis of the disease is not well known, however it would appear that the concomitance of a double sensitivization of the red blood cells to the P. falciparum red blood cells and to the amino-alcohols is necessary to provoke the hemolysis. EVOLUTION: The severity of the clinical picture often requires initial management in intensive care unit. Nowadays, however, prognosis is good and the disease usually regresses without after effects.