IT IS THE 8-AMINOQUINOLINE ANTIMALARIAL. IT IS READILY ABSORBED, RAPIDLY METABOLISED AND ONLY A SMALL PROPORTION OF THE ADMINISTERED DOSE IS EXCRETED AS THE PARENT DRUG. PLASMA CONCERTRATION REACHES A MAXIMUM IN ABOUT 6 HOURS. PRIMAQUINE IS HIGHLY ACTIVE AGAINST THE PRIMARY EXOERYTHROCYTIC FORMS OF P.VIVAX AND P.FALCIPARUM. THE DRUG IS ALSO ACTIVE AGAINST THE ASEXUAL BLOOD FORMS OF P.FALCIPANEM & ITS GREAT CLINICAL VALUE LIE LIES IN THE MEDICALLY CURATIVE TREATMENT OF VIVAX MALARIA.