Sweet Wormwood

Artemesia Annua

Qinghao, Sweet Annie.

Edible Uses

Edible Uses: Condiment.

An essential oil in the leaves is used as a flavouring in spirits such as vermouth, The use of wormwood in beverages dates back many centuries, perhaps as far back as the Saracens. Various methods of consumption have been used throughout history, including mixing the essential oil with beer or adding wormwood seeds to the distillation of whisky, and the mixing of the wormwood drug absinthol with anise to produce the intoxicating beverage known as absinthe. Overuse of this drink had devastating effects in Europe in the 18th century, with overindulgence known to have brought about paralysis.

Medicinal Uses

Antibacterial; Antiperiodic; Antiseptic; Carminative; Digestive; Febrifuge.

Qing Ho, better known in the West as sweet wormwood, is a traditional Chinese herbal medicine. An aromatic anti-bacterial plant, recent research has shown that it destroys malarial parasites, lowers fevers and checks bleeding. It is often used in the tropics as an affordable and effective anti-malarial. The leaves are antiperiodic, antiseptic, digestive, febrifuge. An infusion of the leaves is used internally to treat fevers, colds, diarrhoea etc. Externally, the leaves are poulticed onto nose bleeds, boils and abscesses. The leaves are harvested in the summer, before the plant comes into flower, and are dried for later use. The plant contains artemisinin, this substance has proved to be a dramatically effective anti-malarial against multi-drug resistant Plasmodium spp. Clinical trials have shown it to be 90% effective and more successful than standard drugs. In a trial of 2000 patients, all were cured of the disease. Also used against malaria is an alcohol extract of the dried leaves, with the wormwood species Artemisia annua showing far greater antimalarial potential than extracts from over 30 other species in lab tests. Wormwood is often used in conjunction with other herbs to deal with gallbladder disorders and flatulence. The seeds are used in the treatment of flatulence, indigestion and night sweats.Orally wormwood is taken for loss of appetite, indigestion and gastrointestinal problems. The constituents of wormwood include artemisinin, absinthin, anabsinthin, and a volatile oil that is 70% thujone.

Although Wormwood is generally regarded as safe when used appropriately and for short durations, it should not be taken in large amounts or long-term. This herb has been declared unsafe for use during pregnancy due to its uterine and menstrual stimulating effects. Due to the lack of sufficient reliable information, wormwood should not be used while breastfeeding. Habitual large doses of wormwood can cause a range of undesirable effects. These may include restlessness, insomnia, nightmares, vomiting, abdominal pains, dizziness, tremors, convulsions and urinary tract disfunction. Thujone’s toxicity can cause various effects as the amount of wormwood consumed increases, including seizures, delerium and hallucinations in extreme cases. Some researchers believe that thujone’s mind altering effects are similar to THC in marijuana.

There are some beneficial uses of this wormwood constituent however, as thujone shows promise as an antioxidant. It also appears to have moderate antimicorbial and antifungal properties. The most famous therapeutic use of wormwood is the expulsion of parasitic worms. Many reference works continue to list wormwood as an effective vermifuge, and some also list it for it’s antibacterial and antifungal actions. Historically wormwood has been used as a parasitic worm killer, tonic and to induce perspiration. Other traditional applications include regulating menstruation and reducing fever. In times past wormwood was thought to counteract poison. When rumours of plague breaking out in London hit the streets in 1760, merchants reported running out of wormwood due to the huge public demand.

Artemisinin is a herbal treatment for parasitic infections and malaria that also protects against particular types of cancer. Extracted from the plant Artemesia Annua, Artemisinin has been used for centuries to kill parasites, particularly worms and flukes. These parasites, which are present in us all, create a burden for the body, sapping energy resources and creating by-products that need to be excreted. Artemisinin has also proven itself as a safe and effective treatment for malaria in over two million patients, and now studies are showing that Artemisinin is effective against a wide variety of cancers as shown in a series of successful experiments. The most effective is leukemia and colon cancer. Intermediate activities were also shown against melanoma, breast, ovarian, prostate, CNS and renal cancer.

Artemisinin’s method of action: Artemisia Annua is a lactone compound which contains two oxygen atoms linked together; this is called an endoperoxide bridge which is essential for its anti-cancer activity. All cells require iron in order to divide and function, but rapidly dividing cancer cells require significantly higher iron concentrations to survive than normal, healthy cells do. Since cancer is characterized by out-of-control cellular division, cancer cells have exceedingly higher iron concentrations than do normal cells. When Artemisia Annua or its derivatives come into contact with iron, a chemical reaction takes place which creates newly formed charged particals (ions) called free radicals. These powerful free radicals attack and bind with cellular membranes, killing these cells (which are primarily cancer cells) by causing them micromolecular damage. It should also be noted that, compared to normal cells, cancer cells sequester relatively large amounts of iron mainly in the form of holotransferrin. Artemisia Annua has been shown to cause rapid, as well as extensive, damage and death in cancer cells while exhibiting relatively low toxicity in healthy, normal cells. By this same mechanism, Artemisinin becomes toxic to malaria parasites when it reacts with the high iron content of the parasites, generating free radicals, and leading to damage to the parasite.

It is imperative to note that, on the surfaces of cancer cells there are significantly more transferrin receptors; these are cellular pathways that allow iron to enter the cell. According to Lai, in the case of breast cancer, (for instance), cancer cells have five to fifteen times more transferrin receptors on their surfaces than do the normal, healthy breast cells. Thus, in severe and critical cases, the supplementation of high doses of iron may cause a more powerful attack of Artemisia Annua on these iron-loving cancer cells, weakening them, and making them less resistant (or more suseptable) to other treatments as well.

In the laboratory at the University of Washington, Dr. Henry Lai showed that Artemisia Annua killed virtually all human breast cancer cells exposed to it in the test tube within 16 hours. At the same time, nearly all of the normal, healthy cells exposed to Artemisia Annua over the 16 hours were still alive. Lai and his researchers also reported that a dog with a type of bone cancer known as Osteosarcoma, so severe that it was unable to walk across the lab, made a complete recovery within five days of receiving Artemisia Annua treatment. The x-rays on this animal revealed that the tumor "had basically disappeared".

Tea: Add 1 litre of boiling water to five - nine grams of dried herb, stir the mixture briefly and cover the container for 10 minutes. Filter out the plant material and squeeze gently to release residual water. Allow the Tea to cool to room temperature. This is said to be the most efficient method of tea preparation, yielding 94.5 mg of artemisinin in one liter of tea prepared from nine grams of leaves. Extended boiling (30 minutes) reduces the yield considerably, presumably due to the chemical lability of artemisinin.


Other Uses

Essential; Herbicide; Miscellany.

Wormwood was strewn about chambers to repel moths, fleas and other insects. The plant is used in China as a medium for growing Aspergillus which is used in brewing wine. The substances mentioned above in the medicinal uses, used in the treatment of malaria, also show marked herbicidal activity. The plant yields 0.3% essential oil. This has an agreeable, refreshing and slightly balsamic odour and has been used in perfumery.

Cultivation details

The wormwood bush can grow to a height of 2 meters, and produces a number of bushy stems that are covered with fine, silky grey-green hairs. An easily grown plant, succeeding in a well-drained circumneutral or slightly alkaline loamy soil, preferring a sunny position. Wormwood produces small yellow-green flowers from Summer through to early autumn or fall. Plants are longer lived, more hardy and more aromatic when they are grown in a poor dry soil. A fast-growing plant, different sources say annual, biennial, or perennial, it is tall but neat in habit with a handsome fragrant foliage and is useful for filling gaps at the back of a border. It has become a weed of waste places in many areas of the world. The plant is extremely vigorous and essentially disease and pest free. Wormwood is a determinate short-day plant, susceptable to photoperiodic stimulation, making it unsuitable for the tropics because flowering will be induced when the plants are very small. Most collections of artemisia derive from natural stands with highly variable artemisinin content, some as low of 0.01%. Selections from Chinese origin vary from 0.05 to 0.21%. Swiss researcher N. Delabays reports a clonal selection derived from Chinese material which produces 1.1% artemisin but is very late flowering; proprietary hybrids have been obtained with somewhat lower content but flower earlier.


Seed - sow spring in a cold frame and plant out in late spring or early summer. Alternatively, the seed can be sown late spring in situ.