Artemisia (wormwood) is often used in parasite cleansing formulas. I could find only a few studies on this herb pertaining to killing worms.

http://www.abdn.ac.uk/organic/organic_14c.php


Many wormwood species have deworming properties. Common mugwort (Artemisia vulgaris) is effective against protostrongylus, Dictyocaulus and Bunostomum.
However, common wormwood (Artemisia absinthium) must be used with caution.

Similarly, Eurasian wormwood (Artemisia cina) is a desert plant that is used to make santonin and the homeopathic remedy Cina, both used as dewormers. Santonin is extracted from dry buds of the plant. It acts against most parasites except Echinococcus. Macleod (1997) has also reported that santonium is used as a vermicide against ascaris worms.

The dried, powdered shoots of Artemisia herba-alba wormwood (a species common to North Africa) proved to be highly effective against Haemonchus contortus (Idris et al.,1982) and Hedera helix is effective against liverfluke in sheep (Julien et al., 1985).


Cooper and Gordon (1996) measured the anthelmintic activity of the extracts of the aerial parts of wormwood (Artemisia absinthium), Tansy (Tanacetum vulgare), greater birdsfoot trefoil (Lotus pedunculatus) and the bark of Scot's pine (Pinus sylvestris). They further reported that high doses of wormwood and tansy, and medium doses of pine resulted in lower number of worms than in control animals but there were no significant differences between the treatments.

In another study in Cameroon Ndi et al. (1999) conducted a study in 9 groups of 8 calves using four indigenous plant species namely, Terminalia glaucescens, Veronia amygladina, Solanum aculeastrum and Khaya anthotheca. They found that S. aculeastrum, K. anthotheca and V. amygladina were effective with faecal egg count reductions of 34.4, 52.4 and 55.8 % respectively for Haemonchus sp., Trychostrongylus sp., Strongyloides papillosus., Bunostomum sp., Oesophagostomum sp and Cooperia sp , 21 days after treatment.

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http://www.drugs.com/npp/wormwood.html


Crohn disease - Clinical data

In Germany, a double-blind, placebo-controlled trial examined the efficacy of administering an herbal blend (3 × 500 mg per day) containing wormwood versus placebo over 10 weeks in 40 patients suffering from Crohn disease. Twenty patients received the treatment, while the remaining patients received placebo. All patients achieved good control of their symptoms through use of steroids and other medications. Outcome measures included the effect of wormwood on steroid dependence and psychological measures, such as decline in symptoms of depression often associated with Crohn disease. Physical and psychological symptoms worsened for patients taking placebo. However, those receiving wormwood showed gradual improvement of symptoms, with 13 patients nearly free of physical and psychological symptoms and less dependent on steroids. Patients suffered no serious adverse reactions.

Omer B , Krebs S , Omer H , Noor TO . Steroid-sparing effect of wormwood ( Artemisia absinthium ) in Crohn's disease: a double-blind placebo-controlled study . Phytomedicine . 2007 ; 14 ( 2-3 ): 87-95 .



In vitro data

The essential oils of wormwood have antimicrobial activity against Escherichia coli , Salmonella enteritidis , Pseudomonas aeruginosa , Klebsiella pneumoniae , Staphylococcus aureus , C. albicans , and Aspergillus niger. The activity was considered comparable with that of erythromycin.

Blagojevic P , Radulovic N , Palic R , Stojanovic G . Chemical composition of the essential oils of Serbian wild-growing Artemisia absinthium and Artemisia vulgaris . J Agric Food Chem . 2006 ; 54 ( 13 ); 4780-4789