Anthelmintic

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Anthelmintics or antihelminthics are drugs that expel parasitic worms (helminths) from the body, by either stunning or killing them. They may also be called vermifuges (stunning) or vermicides (killing).

1 Pharmaceutical classes 2 Natural anthelmintics 3 Anthelmintic resistance 4 Development of resistance 5 References

5.1 Footnotes 5.2 General references

6 External links

[edit] Pharmaceutical classes

Examples of pharmaceuticals used as anthelmintics include:

Albendazole â€“ effective against threadworms, roundworms, whipworms, tapeworms, hookworms Diethylcarbamazine â€“ effective against Wuchereria bancrofti, Brugia malayi, Brugia timori, tropical pulmonary eosinophilia, loiasis Mebendazole â€“ effective against pinworms, roundworms and hookworms Niclosamide â€“ effective against tapeworms Ivermectin â€“ effective against most common intestinal worms (except tapeworms) Suramin Thiabendazole â€“ effective against roundworms, hookworms Pyrantel pamoate â€“ effective against most nematode infections Levamisole Piperazine family Praziquantel â€“ effective against nematodes, some trematodes Triclabendazole â€“ effective against liver flukes Octadepsipeptides (eg: Emodepside) â€“ effective against a variety of gastrointestinal helminths Amino Acetonitrile derivatives (eg: Monepantel): effective against a variety of gastrointestinal helminths including those resistant to the other drug classes.

Please note that many of these pharameuticals are extremely toxic. Taken in improper dosages they can be dangerous to humans as well as lethal to parasites.

[edit] Natural anthelmintics

Examples of naturally occuring anthelmintics include:

Tobacco (Nicotiana tabacum & Nicotiana rustica)^[1] Black walnut (Juglans nigra) wormwood (Artemisia absynthium) clove (Syzygium aromaticum) tansy tea (Tanacetum vulgare) Hagenia (Hagenia abyssinica) kalonji (Nigella sativa) seeds male fern (Dryopteris filix-mas) Plumeria (P. acutifolia or P. rubra) in Brazilian folk medicine.^[2] Peganum harmala is used as an anthelmintic.^[3]

Please note that many natural vermifuges or anthelmintics are poisonous and, in improper dosages, dangerous to humans as well as parasites.

[edit] Anthelmintic resistance

The ability of worms to survive treatments that are generally effective at the recommended dose rate is considered a major threat to the current future control of worm parasites of small ruminants and horses.

The clinical definition of resistance is a 95% or less reduction in a "Fecal Egg Count" test.^[clarify]

[edit] Development of resistance

Treatment eliminates worms whose genotype renders them susceptible. Worms that are resistant survive and pass on their "resistance" genes. Resistant worms accumulate and finally treatment failure occurs.

[edit] References

[edit] Footnotes

^ The Merck Index, 12th Ed., page 1119: entry 6611 Nicotine, Merck & Co. 1996 ^ Arnold, M.D., Harry L. (1968). Poisonous Plants of Hawaii. Tokyo, Japan: Charles E. Tuttle Co., 51. ^ "Peganum harmala" (2004). Retrieved on 2008-02-02.