P-alaxin, an artemisinin based combined therapy is very effective in treating malaria infection in areas of high resistance to conventional antimalarial drugs. It is an anti-malaria drug that is composed of dihydroartemisinin and piperaquine phosphate. The drug combination is known to be effective against P. vivax, P. malariae and the multi-resistant P. falciparum malaria parasites. Dihydroartemisinin is the active metabolite of artemisinin and its derivatives. These derivatives havemore potent blood schizonticidal activity than the parent compound. Dihydroartemisinin is the most potent antimalarial of this group of compounds but it is also the least stable. Oral dihydroartemisinin is rapidly absorbed and has a short elimination half-life. Piperaquine phosphate, a bisquinoline, structurally related to chloroquine has been shown to exhibit cardiovascular toxicity in overdose with significant electrophysiological effects on the ear.