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Spring Cleaning? What About Intestinal
Parasites?
Spring is traditionally a time for cleaning.
This was well-recognized by European herbalists who used a number of
herbs as "spring tonics"
or "spring cleansers." Many of these spring tonics provided
much needed vitamins
after a lengthy period of consuming stored foods. But they also included
the depurative herbs (herbs which clean the blood by unknown mechanisms)
and herbs for promoting digestion, including the bitter herbs wormwood
and gentian. Wormwood, as the name implies, was also traditionally used
to treat gastrointestinal worm infestation. So it could be that this
aspect was also part of the use of spring tonics.
Whether this is the case or not, it is true to say that the plant world has
long provided options to assist in the control of intestinal parasites. A few
of the more popular herbs are viewed below, together with a significant and
highly active anthelmintic herb from Traditional Chinese Medicine. But the
main thrust of this review is to suggest that synergistic activity via a combination
of these key herbs (with other herbal treatments as well to support digestion
and immunity etc.) will yield the best results.
Wormwood
Artemisia absinthium is well known to herbalists with particular application
to treating nematode infestation, especially infestation with Enterobius
or Ascaris.1,2 Wormwood has been used as an anthelmintic since ancient times
and is currently utilized in many countries throughout the world for this
purpose. Wormwood tincture is employed in the West Indies as a worm preventative.3
Wormwood has also been used for the de-worming of horses, cows and sheep.4,5
Key Constituents
Constituents of the aerial parts of wormwood include bitter substances (sesquiterpene
lactones, mainly absinthin) and an essential oil containing mainly terpenes.
The essential oil contains the potentially toxic monoterpene thujone and
for this reason the recommended therapeutic doses of wormwood should not
be exceeded.6
Anthelmintic Activity
In vitro wormwood aqueous extract demonstrated anthelmintic activity towards
the nematode Trichostrongylus colubriformis.7 Thujone is also implicated
in the anthelmintic activity of wormwood. Experiments carried out in Edinburgh
in 1955 indicated the efficacy of thujone in eliminating Ascaris lumbricoides.8
Other Related Activity
Wormwood aqueous extract and alcohol extract strongly inhibited the in vitro
growth of the parasitic protozoa Naegleria fowleri. The sesquiterpene lactone
fraction isolated from the alcohol extract was also active.9
Wormwood powder (1.5 g/day) provided effective treatment for acute intestinal
amebiasis in an uncontrolled trial of 20 patients. Symptoms were relieved and
70% of cases were cleared of the protozoa Entamoeba histolytica according to
stool analysis.10
Wormwood is also used to treat other gastrointestinal conditions such as appetite
loss, disturbed digestion, flatulence and disordered bile flow.11 Clinical
trials have demonstrated the ability of wormwood to increase the flow of gastric
enzymes, pancreatic enzymes and bile.12,13
Black Walnut Hulls
A globular fruit is produced from the black walnut tree which contains a corrugated
nut in its yellowish-green hull (also called husk or fruit wall). Upon ripening
the hull softens and turns dark brown to black due to chemical oxidation.
A decoction of the hull of Juglans nigra fruit has been used traditionally
to expel worms.2
Key Constituents
The unripe hulls of Juglans nigra contain 1,4-naphthoquinones including juglone
and plumbagin.14 The juglone content in hulls varies with different cultivars
and different months of growth.15
Anthelmintic Activity
In vitro studies indicate that plumbagin inhibited the motility of and hatching
of Haemonchus contortus first stage larvae. Plumbagin was larvacidal towards
Ascaris suum at the highest test concentration (100 mM). Partial inhibition
of embryonic development of A. suum occurred with plumbagin.16 The authors
suggested that because of the relatively high doses required for the maximal
effect on inhibiting the development of larval stages, plumbagin may not
find practical application. The combination with other anthelmintic herbs
would however, boost the activity of plumbagin.
Stemona
Radix Stemona, the tuberous root of Stemona sessilifolia, Stemona tuberosa
or Stemona japonica, is used in Traditional Chinese Medicine (TCM) mainly
for the treatment of acute and chronic cough. Externally it is used for the
treatment of fungal infections, lice infestation and as an enema for pinworm
infestation.17-19 In addition to its primary use for the treatment of cough,
in Vietnam Stemona japonica root is prescribed for Ascaris infestation and
is used externally to treat scabies (mite infestation).20
Key Constituents
A series of complex alkaloids have been isolated from the root of these Stemona
species.21The unusual and complex alkaloids exist only in Stemona plants
and in a few related species and include tuberostemonine and stemonine.22
Anthelmintic Activity
Tuberostemonine, an alkaloid isolated from Stemona sessilifolia, S. tuberosa
and S. japonica root,21 paralyzed the motility of Angiostrongylus cantonensis
in vitro and showed contractive effects on the motility of Dipylidium caninum
and Fasciola hepatica. The experimental anthelmintic activity of crude extract
of Stemona may be due to the action of tuberostemonine23 and related alkaloids.
One hundred and forty cases of ancylostomiasis (hook worm infestation) were
treated with the herb. After 3 months, follow-up examination of 110 cases revealed
a negative rate of 94.5%. Another group of 48 cases was effectively treated
with the herb decoction; 116 worms, all from the duodenum, were expelled. However,
the same method did not show any anthelmintic effects in later trials.24Alcoholic
extracts will probably work better than decoction.
The suppository prepared from the herb was used to treat 40 children with oxyuriasis
(infestation with a type of nematode); 16 of them were cured. Twenty-seven
out of 63 cases were cured by the herb powder. Dosage: Suppository — (12.5
g each). One suppository was inserted into the rectum at 8 pm, another at 10
pm every night for one week, then every other night for another week. Powder — 1.5
g 3 times daily for 3 days.24
Clove Bud Essential Oil
The dried, unopened flower bud of Syzygium aromaticum has been used in Ayurveda
and Western herbal medicine as a carminative and aromatic.2,25 It has recently
been popularized as a worm
treatment. Therapeutic indications for clove bud include nausea, flatulence,
dyspepsia and to assist the action of other herbal remedies.2,25,26
In traditional Thai medicine the essential oil is used as a carminative and
to treat stomach ache, in addition to the well-known topical application of
toothache.27 In Indonesian traditional medicine clove oil is taken with beer
to protect against abdominal pain! Clove bud is also used in this traditional
system to alleviate flatulence.28
Key Constituents
Key constituents of clove bud include an essential oil (15-20%, consisting
mainly of eugenol, eugenol acetate, beta-caryophyllene), flavonoids, tannins
and phenolic acids.29 Eugenol is a major constituent of clove bud essential
oil (80-85%).30
Anthelmintic Activity
Clove powder demonstrated potent anthelmintic activity in vitro towards Pheretima
spp. (earthworms). At this time earthworms were used as a model to investigate
anthelmintic activity. Suspension of clove powder was more than 5 times more
potent than a water extract of cloves and clove powder was 4.5 times more
potent than powdered fresh garlic. Suspension of clove powder was 7.3 times
more active than the anthelmintic drug piperazine, whereas the water extract
of clove was of similar potency.31 Piperazine is an anthelmintic drug which
has been used to treat pinworm and roundworm infections in humans for decades.
Both the water and methanol extracts of clove bud were strongly active in a
nematocidal assay.32 The assay used the second-stage larva of the roundworm
Toxocara canis, which at the time of the study was highly resistant to anthelmintic
drugs. The relative movability (RM) value compares the extent of movement of
the test population which has been exposed to the anthelmintic agent with the
movability of the control sample. Strong activity was defined as a RM value
of 0 (at which all larvae are dead). A value of 100 indicates no activity (no
disabling effect on the larvae), and increasingly lower RM values approaching
0 indicate stronger activity of the extracts against the larvae.
A value of 0 was obtained for clove methanolic extract at both concentrations
(1 mg/mL, 10 mg/mL) and both time frames (6 h, 24 h) and for water extract
(10 mg/mL) at 24 hours. Piperazine produced a RM value of 32 for 1 mg/mL after
24 hours of incubation in the same assay and other anthelmintic drugs such
as phenothiazine produced a RM value of 0 under the same conditions. Eugenol
produced a RM value of 0 at 1 mg/mL at 24 h, and a value of 50 at the lower
concentration of 0.1 mg/mL after the same time period. The nematocidal activity
of eugenol has been confirmed in another study using the same assay.33
Clove oil killed Anisakis spp. larva in vitro.34 Eugenol also demonstrated
potent anthelmintic activity towards Caenorhabditis elegans in vitro35 and
Rhabditis macrocerca and Ascaris suum in vitro and in vivo in mice (route unknown).36
Potential for Synergistic Anthelmintic Activity
The phenomenon known as bursting of worm larvae occurs when the outer covering
of the larva is torn, resulting in protrusion of its intestine. Nematocidal
assays can discover active principles that cause the killing and/or bursting
of worm larvae. A constituent that has no nematocidal activity may produce
bursting when combined with a nematocidal agent.
Eugenol caused bursting of worm larvae in the Toxocara assay described above.32
The activity of eugenol on its own was relatively weak (11%) but it caused
marked bursting of worms (90-91%) when combined with tannins (either condensed
or hydrolyzable (tannic acid)). Tannins are not larvicidal by themselves, but
they cause bursting when combined with a larvacidal compound, as has been demonstrated
in the same assay previously.37 In order to cause bursting, coexistence of
both the anthelmintic compound and the bursting factor is necessary. The bursting
activity of tannins (when combined with the suitable larvacidal substance)
increased with increasing degree of condensation for condensed tannins and
with increasing proportion of phenolic groups for hydrolyzable tannins.
From similar nematocidal studies investigating other essential oil components
it was concluded that eugenol in combination with tannins can, even at lower
concentration than its MLC (minimum lethal concentration), cause the bursting
of worms if a large amount of (another) nematocidal constituent is present.
(MLC was defined as the lowest concentration producing a RM value of 0 after
24 hours incubation, determined for eugenol as 0.33 mg/mL.)32
Conclusions from this and other studies by the same research team indicate
that:
• a balance between the hydrophilicity (water-soluble) and hydrophobicity
(fat-soluble) of the constituents is important for the larvacidal activity;38
• the bursting activity may be caused not only by tannins but also by other
nonvolatile32 and volatile constituents;33
• a different bursting feature was observed for the tannin-nematocide mixture
compared to the bursting caused by essential oil alone33 suggesting a different
mechanism of action;
• the synergistic action of tannins and an anthelmintic not only damages
the worms irreversibly, but also, in some instances markedly reduced the required
amount of the anthelmintic.37
This research suggests the value of combining various herbal agents for a synergistic
anthelmintic activity. It also implies that combination of anthelmintic herbs
with tannin-containing herbs such as green tea and particularly herbs containing
condensed tannins such as grape seed extract will enhance their activity.
Recent Anthelmintic Research
In vitro tests conducted at a government laboratory in Brisbane in 2002 using
a number of herbal extracts and essential oils have indicated that clove
bud and Stemona have definite positive anthelmintic activity towards a sheep
intestinal nematode prevalent in this locality.39
The testing included egg hatch assay, larval development assay and infective
larvae assay. At the tested dosage clove bud gave a convincing kill of the
larvae population, rather than just immobilization. A field trial testing a
number of herbs and essential oils for the treatment of worm infestation in
sheep is pending.
Suggested Combinations for Increased Activity
The following treatments would combine well and provide synergistic anthelmintic
activity with the wormwood, black walnut hulls, Stemona and clove bud essential
oil mentioned above:
• tannin-containing herbs, especially preparations containing green tea
(Camellia sinensis) and grape seed (Vitis vinifera) extract. These herbs should
be taken
concomitantly with the anthelmintic herbs.
• holy basil (Ocimum sanctum) essential oil, since the leaf has been used
in traditional Ayurvedic medicine as an anthelmintic and the essential oil has
demonstrated potent anthelmintic activity in vitro towards Caenorhabditis elegans.35
In the worm bursting assay outlined above32 methyleugenol demonstrated nematocidal
activity but was devoid of worm bursting activity. The presence of even a small
amount of eugenol (5-10%) in the methyleugenol-tannin mixture caused the bursting
of the worms, particularly when the tannin as of the condensed type.32 Both
eugenol and methyleugenol occur in holy basil essential oil; the amount of
each varies depending upon the chemotype.40
• immune enhancing herbs such as Echinacea, and also preparations containing
Andrographis paniculata and holy basil essential oil: to enhance the body's
natural immune function and assist in the immune response to worm infestation.
Eosinophilia (increased number of eosinophils in the blood) and elevated serum
IgE (gamma-E globulin) levels are features of many helminthic infections.)
• garlic (Allium sativum) has been used as an anthelmintic in western herbal
medicine,1 for example, as a decoction or freshly mashed and administered to
children on an empty stomach.41 Garlic extract was effective against Rhabditis
spp. and the eggs of Ascaris suum in vitro.42 In the Toxocara assay described
above methanol extract of garlic (10 mg/mL) produced a RM value of 0 after
24 hours of incubation.32
• laxative herbs: to promote elimination of the worm infestation (or worm
debris) via the bowel including preparations containing cascara (Rhamnus purshiana)
and yellow dock (Rumex crispus).
• bitter herbs: to promote the gastric acid barrier to resist reinfestation.
I recommend gentian (Gentiana lutea) liquid extract.
• digestive enzyme preparations, such as the latex of Ficus spp. which
contains ficin has been used traditionally in neotropical areas such as the Amazon
as
an anthelmintic.43 However, concomitant intake of digestive enzymes with tannins
may result in the inactivation of the enzymes.
References
1. British Herbal Medicine Association's Scientific Committee.
British Herbal Pharmacopoeia. BHMA, Bournemouth, 1983.
2. Felter HW, Lloyd JU. King's American Dispensatory. 18th Ed,
3rd revision, Volume 1. First published 1905, reprinted Eclectic Medical
Publications, Portland,
1983.
3. Quinlan MB, Quinlan RJ, Nolan JM. J Ethnophamracol 2002; 80(1): 75-83
4. Waller PJ, Bernes G, Thamsborg SM et la Acta Vet Scan 2001; 42: 31-44
5. Uncini Manganelli RE, Camangi F, tomei PE. J Ethnopharmacol 2001; 78(2-3):
171?191
6. Bisset NG (ed). Herbal Drugs and Phytopharmaceuticals. Medpharm Scientific
Publishers, Stuttgart, 1994, pp 45-48.
7. Bara S, Zaragoza C, Valderrabano J. SEMh Congreso 1999: Sociedad Espanola
de Malherbología, Longrono, Spain, November 23-25, 1999, pp 233-240.
8. Albert-Puleo M. Econ Bot 1978; 32: 65-74
9. Mendiola J, Bosa M, Perez N et al. Trans R Soc Trop Med Hyg. 1991; 85(1):
78-79
10. Tahir M, Siddiqui MM, Khan AB. Hamdard Med 1997; 40(3): 24-27
11. Blumenthal M et al (eds). The Complete German Commission E Monographs:
Therapeutic Guide to Herbal Medicines. American Botanical Council, Austin,
1998, pp 232-233.
12. Glatzel H, Hackenberg K. Planta Med 1967; 3: 223-232
13. Baumann IC, Glatzel H, Muth HW. Z Allgemeinmed 1975; 51(17): 784-791
14. Binder RG, Benson ME, Flath RA. Phytochem 1989; 28(10): 2799-2801
15. Lee KC, Campbell RW. HortSci 1969; 4(4): 297-298
16. Fetterer RH, Fleming MW. Comp Biochem Physiol C 1991; 100(3): 539-342
17. Pharmacopoeia Commission of the People's Republic of China. Pharmacopoeia
of the People's Republic of China,'English Ed, Volume I. Chemical
Industry Press, Beijing, 1997, p 173.
18. Chang HM, But PP. Pharmacology and Applications of Chinese Materia Medica.
Volume I. World Scientific, Singapore, 1987, pp 484-488.
19. Bensky D, Gamble A. Chinese Herbal Medicine Materia Medica. Eastland Press,
Seattle, 1986, pp 297-298.
20. World Health Organization. Medicinal Plants in Viet Nam. WHO Regional Office
for the Western Pacific, Manilla, 1990, pp 354-355.
21. Tang W, Eisenbrand G. Chinese Drugs of Plant Origin. Springer-Verlag, Berlin,
1992, pp 957-961.
22. Qin GW, Xu RS. Med Res Rev 1998; 18(6): 375-382
23. Terada M, Sano M, Ishii AI et al. Nippon Yakurigaku Zasshi 1982; 79(2):
93-103
24. Chang HM, But PP. Pharmacology and Applications of Chinese Materia Medica..
Volume 1. World Scientific, Singapore, 1987, pp 484-488.
25. Chopra RN, Chopra IC, Handa KL et al. Chopra's Indigenous Drugs
of India, 2nd Ed, 1958, reprinted Academic Publishers, Calcutta, 1982, pp 172-173.
26. Pharmaceutical Society of Great Britain. British Pharmaceutical Codex 1934.
The Pharmaceutical Press, London, 1941, pp 288-289.
27. Farnsworth NR, Bunyapraphatsara N (eds). Thai Medicinal Plants. Medicinal
Plant Information Center, Bangkok, 1992, pp 233-236.
28. Dharma AP. Indonesian Medicinal Plants. Balai Pustaka, Jakarta, 1987, pp
52-54.
29. Bisset NG (ed). Herbal Drugs and Phytopharmaceuticals: A Handbook for Practice
on a Scientific Basis. Medpharm Scientific Publishers, Stuttgart, 1994, pp
130-131.
30. Battaglia S. The Complete Guide to Aromatherapy. Virginia, Queensland,
The Perfect Potion, 1995, pp 235-236.
31. Krishnakumari MK, Majumder SK. J Sci Indust Res 1960; 19C: 202-204
32. Kiuchi F, Nakamura N, Miyashita N et al. Shoyakugaku Zasshi 1989; 43(4):
279-287
33. Nakamura N, Kiuchi F, Tsuda Y et al. Shoyakugaku Zasshi 1990; 44(3):
183-195
34. Oishi K, Mori K, Nishiura Y. Nippon Suisan Gakkaishi 1974; 40(12): 1241-1250
35. Asha MK, Prashanth D, Murali B et al. Fitoterapia 2001; 72(6): 669-670
36. Valette G, Cavier R, Debelmas J. Ann Pharm Franc 1953; 11: 649-653
37. Kiuchi F, Tsuda Y, Kondo K et al. Chem Pharm Bull 1988; 36(5): 1796-1802
38. Kiuchi F, Miyashita N, Tsuda Y et al. Chem Pharm Bull 1987; 35(7): 2880-2886
39. Information on file. MediHerb Research Laboratory, University of Queensland,
St. Lucia, Queensland 4072, Australia.
40. Lawrence BM. Essential Oils 1988-1991. Carol Stream: Allured Publishing
Corporation, 1993, pp 200-201
41. Guarrera PM. J Ethnopharmacol 1999; 68(1-3): 183?192
42. Chybowski J. Herbal Pol 1997; 43(4): 383-387
43. Hansson A, Veliz G, Naquira C et al. J Ethnopharmacol 1986; 17(2):105-138
Phytotherapy Review & Commentary
by Kerry Bone, FNIMH, FNHAA
P.O. Box 713 • Warwick QLD 4370, Australia
+61 7 4661 0700 • Fax +61 7 46610788 • www.mediherb.com
FNIMH = Fellow, National Institute of Medical Herbalists (UK)
FNHAA = Fellow, National Herbalists Association of Australia
Acknowledgment
The contribution of Michelle Morgan in the preparation of this article
is gratefully acknowledged.
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