Introduction
Artesunate is indicated for the initial treatment of severe malaria. The World Health Organization recommends artesunate as first line treatment for severe malaria. Artesunate was developed out of a need for a more hydrophilic derivative of artemisinin.
Uses
Artesunate is artesunate is an artemesinin derivative indicated for the initial treatment of severe malaria.
Artesunate is indicated for the initial treatment of severe malaria in adult and pediatric patients.
Associated Conditions
Pharmacodynamics
Artesunate is an artemisinin derivative that is metabolized to DHA, which generates free radicals to inhibit normal function of Plasmodium parasites. It has a short duration of action due to its short half life, and a moderate therapeutic index. Patients should be counselled regarding the risk of post treatment hemolytic anemia and hypersenstivity.
Mechanism of Action
Artesunate is metabolized to the active DHA. the endoperoxide bridge of DHA reacts with heme, generating free radicals which inhibit protein and nucleic acid synthesis of the Plasmodium parasites during all erythrocytic stages. Reactions with these free radicals can also lead to alkylation of parasitic proteins such as a calcium adenosine triphosphatase and EXP1, a glutathione S-transferase.
Absorption
The Cmax of artesunate is 3.3µg/mL while the Cmax of the active metabolite DHA is 3.1µg/mL. The AUC of artesunate is 0.7µg*h/mL while the AUC of DHA is 3.5µg*h/mL. After intravenous artesunate, DHA has a Tmax of 0.5-15 minutes in adult patients and 21-64 minutes in pediatric patients. Intramuscular artesunate has a Tmax of 8-12 minutes. Infants less than 6 months old will have a higher AUC due to an undeveloped UGT metabolic pathway.
Volume of Distribution
The volume of distribution of artesunate is 68.5L while the volume of distribution of DHA is 59.7L.
Protein Binding
Artesunate and its metabolite DHA are approximately 93% protein bound in plasma. Artesunate can bind to serum albumin.
Route of Elimination
The main route of elimination in humans is unknown. In rats, a dose of artesunate is 56.1% eliminated in the urine and 38.5% in the feces.
Half Life
The elimination half life of artesunate is 0.3h with a range of 0.1-1.8h. The elimination half life of DHA is 1.3h with a range of 0.9-2.9h. Half life after intramuscular administration is 48 min in children and 41 min in adults.
Clearance
The clearance of artesunate is 180L/h while the clearance of DHA is 32.3L/h.
Toxicity
Data regarding overdoses of artesunate are rare. Patients experiencing an overdose may present with pancytopenia, melena, seizures, multiorgan failure, and death. Treat overdose with symptomatic and supportive measures.
Food Interactions
No interactions found.
