Dihydroartemisinin is a drug used to treat malaria. Dihydroartemisinin is the active metabolite of all artemisinin compounds and is also available as a drug in itself. Chemically, it is a sesquiterpene lactone containing an endoperoxide bridge that is essential for antimalarial activity; molecular formula C15H24O5 and molecular weight 284.35 g/mol. The compound acts rapidly against Plasmodium blood stages by generating reactive species after interaction with heme iron within infected erythrocytes, producing fast parasite clearance. It has rapid absorption after oral administration and a short elimination half-life measured in hours, which is why it is routinely deployed in combination therapies with longer acting partner drugs to prevent recrudescence and resistance. Dihydroartemisinin is manufactured and formulated under GMP for use in fixed dose combinations such as dihydroartemisinin-piperaquine and is sensitive to moisture and heat so that appropriate storage conditions are required to maintain potency.
Parent: Artemisinin
Typical quality specifications for dihydroartemisinin API control related substances and degradation products by validated HPLC methods and follow ICH principles; common related compounds include artemisinin, artemether, artesunate, arteether, mono- and di-hydroxylated DHA derivatives, deoxy derivatives, dimers and other oxidative degradation products. Typical impurity limits used in pharmacopoeial and regulatory API specifications are individual identified related substances not more than 0.1 to 0.5 percent by area, any single unknown impurity not more than 0.1 to 0.2 percent, and total impurities generally controlled to not more than about 1.0 to 2.0 percent, with residual solvents and elemental impurities limited according to ICH Q3C and Q3D respectively. Exact limits and test methods should be taken from the applicable monograph or the product master file because numerical limits vary with formulation, intended use and regulatory authority.
Dihydroartemisinin rapidly kills Plasmodium parasites in the bloodstream by producing reactive species after cleavage of its endoperoxide bridge in the presence of heme iron; it is used to achieve quick parasite clearance and is administered as part of artemisinin-based combination therapies to reduce treatment failure and slow resistance development.
Common adverse effects reported include nausea, vomiting, headache, dizziness and transient elevations in liver enzymes; less common but important risks include hypersensitivity reactions, delayed hemolytic anemia after treatment in some patients and rare cardiac or neurologic events. Clinical monitoring and reporting of adverse events is recommended.
Safety data in pregnancy are limited for the first trimester; many guidelines recommend using artemisinin-based combinations in the second and third trimesters when indicated because benefits outweigh risks for treating malaria, but first trimester use should follow local guidance and involve a clinician assessment of risks and benefits.
Follow the prescribing information and clinician instructions. Dihydroartemisinin is most often given as part of a fixed dose combination and must be taken for the full prescribed course to ensure cure and reduce resistance risk. Some combination products have improved absorption when taken with food, particularly a fatty meal; never alter dose or stop therapy without consulting a healthcare professional.
