Artemisia has been shown to be effective in the treatment of malaria.
Artemisia annua is an herb traditionally used in Chinese medicine to treat fever, inflammation, and malaria. A compound in artemisia was shown to be effective in treating malaria in a clinical trial. Another case study showed that artemisia was effective in treating chronic bladder infection. Other studies suggest it may be helpful for osteoarthritis. Artemisia prevented cancer cells from dividing in laboratory studies but clinical trials have not been conducted to support this.
To treat malaria
Several clinical trials support this use. However, recurrence is more likely than with conventional antimalarial treatment.
To reduce inflammation
Preliminary studies suggest that artemisia may be helpful for hip or knee osteoarthritis.
To treat cancer
Laboratory studies have shown some effect. Human data are lacking.
Do Not Take If
You are taking antiseizure medications: Artemisia can induce seizures making such medications less effective.
Hepatitis: In a 52-year-old man following consumption of an herbal supplement containing artemisinin.
Skin rash: With topical use of artemisia.
Hearing loss, ringing in the ears, and dizziness: Possibly related to oral artesunate, an active artemisia compound, among several advanced breast cancer patients in a safety trial. The study drug was otherwise largely well tolerated among patients.
Commonly known as wormwood or sweet sagewort, Artemisia annua has been used in traditional Chinese medicine for reducing fevers, inflammation, headaches, bleeding and for treating malaria.
In vitro studies indicate that artemisinin, the active principle of A. annua, may be an effective treatment for protozoal infections including leishmaniasis (8), Chagas’ disease, and African sleeping sickness (9). Systematic reviews of artemisinin show that it is as effective as quinine in treating both uncomplicated and severe malaria (4)(5). However, increased risk of relapse may limit its uses (6)(7). It is also unclear whether A. annua is effective against strains of malaria that are resistant to quinine.
In one RCT, a low-dose formulation of artemisia produced clinically relevant pain reductions in patients with hip or knee osteoarthritis (3). A subsesquent open-label continuation study demonstrated long-term safety with maintained improvements at 6 months (10).
A. annua has also been investigated for its anticancer properties. Terpenoids and flavonoids isolated from the herb exert cytotoxic effects in several human tumor cell lines (1)(18)(19)(20). The constituents artemisinin and artesunate have been studied as anticancer treatments (25)(26). In a recent safety study in advanced breast cancer patients, oral artesunate as add-on therapy was well tolerated, although it was determined that regular audiological assessments should be included to monitor for ototoxicity (13)(21).
Mechanism of Action
Artemisinin, the active constituent of A. annua, exerts antimalarial effects by free radicals formed via cleavage of the endoperoxide bond in its structure, which are responsible for eradicating the Plasmodium species (23).
Artemisinin induces apoptosis and cell cycle arrest of Leishmani donovani promastigotes (8). It has antiproliferative effects on medullary thyroid carcinoma cells (2), and induces apoptosis in a lung cancer cell line by modulating p38 and calcium signaling (14). In another study, it significantly inhibited cell growth and proliferation, and caused G1 cell-cycle arrest in neuroblastoma cell lines (25). Dihydroartemisinin, a semi-synthetic derivative of artemisinin, demonstrates anti-inflammatory activity by attenuating COX-2 production via downregulation of serine/threonine kinase (AKT) and mitogen activated protein kinase (MAPK) pathways (24). Recent findings suggest that dihydroartemisinin-triggered apoptosis in colorectal cells occurs through the reactive oxygen species (ROS)-mediated mitochondria-dependent pathway (26).
Patients with ulcers or gastrointestinal disorders should not take artemisia (11).
Hepatitis: In a 52-year-old man following consumption of an herbal supplement containing artemisinin (17).
Ototoxicity and vertigo: Possibly related to oral artesunate, an active artemisia compound, among several advanced breast cancer patients in a safety trial (13)(21). The study drug was otherwise largely well tolerated among patients.
Antiseizure medications: Artemisia can induce seizures resulting in decreased efficacy of antiseizure medications (11).
Cytochrome P450 (CYP450) substrates: Artemisia extracts have induced CYP2B6 and CYP3A4 (27) and may affect the serum concentration of drugs metabolized by these enzymes.