amodiaquine

Amodiaquine is an antimalarial medication in the 4-aminoquinoline class. It is used for the treatment of uncomplicated malaria caused by Plasmodium falciparum and, to a lesser extent, Plasmodium vivax. In many malaria programs it is included in fixed-dose combinations with artesunate (artesunate-amodiaquine, ASAQ), which are widely used as a first-line therapy for uncomplicated malaria. Amodiaquine is also employed in preventive regimens in some settings, notably as part of seasonal malaria chemoprevention with sulfadoxine-pyrimethamine and amodiaquine in parts of West Africa.

Amodiaquine itself is a prodrug; after oral administration it is rapidly converted to desethylamodiaquine, the primary active metabolite. These compounds interfere with heme detoxification in the parasite’s digestive vacuole, leading to toxic heme accumulation and parasite death. The drug has a relatively long half-life, providing post-treatment prophylaxis but also raising concerns about resistance if misused.

Pharmacokinetics: Amodiaquine and desethylamodiaquine are absorbed from the gut, undergo hepatic metabolism (notably by CYP2C8), and are excreted mainly in urine and bile.

Safety: Side effects are generally mild but can include gastrointestinal upset, headache, and rash. Serious but rare events include neutropenia, agranulocytosis, hepatotoxicity, and hypersensitivity. Amodiaquine is typically not used as a mono-therapy due to resistance and safety concerns; dosing and use are guided by national programs and WHO recommendations.