Artemisin

A comprehensive overview of the antimalarial drug artemisinin

Artemisinin

Chemical structure of artemisinin

Artemisinin is a group of drugs that possess the most rapid action of all current drugs against Plasmodium falciparum malaria. It is derived from the sweet wormwood plant, Artemisia annua, an herb employed in Chinese traditional medicine.

History

The discovery of artemisinin is attributed to the Chinese scientist Tu Youyou, who was awarded the Nobel Prize in Physiology or Medicine in 2015 for her work. The use of Artemisia annua in traditional Chinese medicine dates back over two thousand years, but it was not until the 1970s that the active compound, artemisinin, was isolated and identified.

Mechanism of Action

Artemisinin and its derivatives, such as artesunate and artemether, are known for their ability to rapidly reduce the number of Plasmodium parasites in the blood of patients with malaria. The exact mechanism of action is not fully understood, but it is believed that artemisinin exerts its effects by generating reactive oxygen species that damage the parasite's cellular structures.

Pharmacokinetics

Artemisinin is poorly soluble in water, which limits its bioavailability. However, its derivatives, such as artesunate and artemether, have been developed to improve solubility and absorption. These derivatives are rapidly metabolized in the body to the active metabolite, dihydroartemisinin, which is responsible for the antimalarial activity.

Clinical Use

Artemisinin-based combination therapies (ACTs) are the recommended treatment for uncomplicated Plasmodium falciparum malaria. ACTs combine artemisinin or one of its derivatives with another antimalarial drug to enhance efficacy and reduce the risk of resistance development. Common combinations include artemether-lumefantrine and artesunate-mefloquine.

Resistance

Resistance to artemisinin has been reported in several regions, particularly in Southeast Asia. This resistance is characterized by a slower rate of parasite clearance from the bloodstream. Efforts are ongoing to monitor and manage artemisinin resistance to ensure the continued effectiveness of ACTs.

Side Effects

Artemisinin and its derivatives are generally well-tolerated. Common side effects include nausea, vomiting, and diarrhea. Rare but serious side effects can include allergic reactions and neurotoxicity, particularly with prolonged use.

Research and Development

Research continues into new derivatives of artemisinin and alternative delivery methods to improve efficacy and reduce the potential for resistance. Additionally, studies are exploring the use of artemisinin in the treatment of other diseases, such as certain types of cancer.

Related pages

• Malaria
• Plasmodium falciparum
• Artemisia annua
• Tu Youyou
• Antimalarial medication