Artemisia absinthium, or common wormwood, is most famous as an ingredient of the alcoholic beverage absinthe. Wormwood is also found in vermouth, but at lower levels. Besides its common function as a flavoring, wormwood also has a long history of medicinal use. A reputed ability to kill intestinal worms gave rise to the herb’s name. Other traditional uses include treating liver problems, joint pain, digestive discomfort, loss of appetite, insomnia, epilepsy, and menstrual problems. The leaves and flowers, and the essential oil extracted from them, are the parts used medicinally.
Common wormwood is a relative of sweet wormwood ( Artemisia annua), a source of the malaria drug artemisinin (also called artemesin).
Wormwood is sometimes recommended today for the treatment of digestive conditions such as intestinal parasites, dyspepsia, esophageal reflux, and irritable bowel syndrome. However, there is no meaningful evidence to indicate that it is effective for any of these conditions. Only double-blind, placebo-controlled studies can show a treatment effective, and only one has been performed using wormwood. (For information on why such studies are essential, see Why Does This Database Rely on Double-blind Studies?)
This 10 week study conducted in Germany evaluated the potential benefits of wormwood for treatment of people with Crohn’s disease, an inflammatory condition of the intestines.9 All forty people enrolled in the study had achieved good control of their symptoms through use of steroids and other medications. Half were given an herbal blend containing wormwood (500 mg three time daily) while the other half were given an identical-appearing placebo. Both researchers and study participants were kept in the dark regarding who was receiving real treatment and who was not. Beginning at week 2, researchers began a gradual tapering down of the steroid dosage used by participants. Over subsequent weeks, most of those given placebo showed the expected worsening of symptoms that the reduction of drug dosage would be expected to cause. In contrast, most of those receiving wormwood showed a gradual improvement of symptoms. No serious side effects were attributed to wormwood in this study.
These are extremely promising findings. However, it must be kept in mind that a great many treatments that show promise in a single study fail to hold up in subsequent independent testing. Further research will be needed to establish wormwood as a helpful treatment for Crohn’s disease. Other proposed uses of wormwood have far weaker supporting evidence. Extremely preliminary indications hint
Other proposed uses of wormwood have far weaker supporting evidence. Extremely preliminary indications hint that wormwood essential oil (like many other essential oils) might have antifungal, antibacterial, and antiparasitic actions.1-5 Note, however, that is does not mean that wormwood oil is an antibiotic. Antibiotics are substances that can be taken internally to kill microorganisms throughout the body. Wormwood oil, rather, has shown potential antiseptic properties. Unfortunately, it is also potentially quite toxic. (See Safety Issues.)
In the study noted above, wormwood was taken at a dose of 500 mg three times daily. A typical traditional dose of wormwood is 3 cups daily of a tea made by steeping 2.5 to 5 grams of wormwood in hot water. Wormwood essential oil should not be used. Long-term use of any form of wormwood (over 4 weeks) should not be attempted except under physician supervision.
There are many unsolved questions about the toxicity of wormwood. When absinthe was popular in the late nineteenth and early twentieth centuries, a mental disorder known as “absinthism”—involving hallucinations, tremors, vertigo, sleeplessness, and seizures—was associated with it. Wormwood contains thujone, a substance thought to be toxic to nerves when taken at high doses, and thujone has been proposed as a factor contributing to absinthism. However, the symptoms of absinthism are also consistent with mere chronic overuse of alcohol, and absinthe does not appear to contain sufficient thujone to cause harm.7 Furthermore, animal studies have generally failed to find significant toxicity with wormwood even at relatively high doses.7,8
Despite the absence of firm evidence, wormwood is still considered a potentially toxic herb, especially if taken over the long term. Wormwood essential oil contains thujone at much higher levels than those found in absinthe, and should be avoided. Wormwood should not be used by young children, pregnant or nursing women, or people with severe liver or kidney disease.
1. Kordali S, Cakir A, Mavi A, et al. Screening of chemical composition and antifungal and antioxidant activities of the essential oils from three Turkish artemisia species. J Agric Food Chem. 2005;53:1408–16.
2. Juteau F, Jerkovic I, Masotti V, et al. Composition and antimicrobial activity of the essential oil of Artemisiaabsinthium from Croatia and France. Planta Med. 2003;69:158–61.
3. Alzoreky NS, Nakahara K. Antibacterial activity of extracts from some edible plants commonly consumed in Asia. Int J Food Microbiol. 2002;80:223–30.
4. Chiasson H, Belanger A, Bostanian N, et al. Acaricidal properties of Artemisia absinthium and Tanacetumvulgare (Asteraceae) essential oils obtained by three methods of extraction. J Econ Entomol. 2001;94:167–71.
5. Mendiola J, Bosa M, Perez N, et al. Extracts of Artemisia abrotanum and Artemisia absinthium inhibit growth of Naegleria fowleri in vitro. Trans R Soc Trop Med Hyg. 1991;85:78–79.
6. Gilani AH, Janbaz KH. Preventive and curative effects of Artemisia absinthium on acetaminophen and CCl4-induced hepatotoxicity. Gen Pharmacol. 1995;26:309–15.
7. Lachenmeier DW, Emmert J, Kuballa T, et al. Thujone—cause of absinthism? Forensic Sci Int. 2005 May 13 [Epub ahead of print]
8. Muto T, Watanabe T, Okamura M, et al. Thirteen-week repeated dose toxicity study of wormwood ( Artemisia absinthium) extract in rats. J Toxicol Sci. 2004;28:471–8.
9. Omer B, Krebs S, Omer H, et. al. Steroid-sparing effect of wormwood ( Artemisia absinthium) in Crohn's disease: a double-blind placebo-controlled study. Phytomedicine. 2007;14:87-95
Last reviewed December 2015 by EBSCO CAM Review Board Last Updated: 12/15/2015