Anthelmintics or antihelminthics are a group of antiparasitic drugs that expel parasitic worms (helminths) and other internal parasites from the body by either stunning or killing them and without causing significant damage to the host. They may also be called vermifuges (those that stun) or vermicides (those that kill). Anthelmintics are used to treat people who are infected by helminths, a condition called helminthiasis. These drugs are also used to treat infected animals.
Pills containing anthelmintics are used in mass deworming campaigns of school-aged children in many developing countries. For example, the treatment of choice for soil-transmitted helminths is mebendazole and albendazole and praziquantel for schistosomiasis and tapeworms.
- Albendazole – effective against threadworms, roundworms, whipworms, tapeworms, hookworms
- Mebendazole – effective against various nematodes
- Thiabendazole – effective against various nematodes
- Fenbendazole – effective against various parasites
- Triclabendazole – effective against liver flukes
- Flubendazole – effective against most intestinal parasites
- Abamectin (and by extension ivermectin) - effective against most common intestinal worms, except tapeworms, for which praziquantel is commonly used in conjunction for mass dewormings.
- Diethylcarbamazine – effective against Wuchereria bancrofti, Brugia malayi, Brugia timori and Loa loa.
- Pyrantel pamoate – effective against most nematode infections residing within the intestines
- Salicylanilide mitochondrial un-couplers (used only for flatworm infections):
- Nitazoxanide – readily kills Ascaris lumbricoides, and also possess antiprotozoal effects
- Praziquantel – effective against flatworms (e.g., tapeworms and schistosoma)
- Octadepsipeptides (e.g.: Emodepside) – effective against a variety of gastrointestinal helminths
- Monepantel (aminoacetonitrile class) - effective against a variety of nematodes including those resistant to other anthelmintic classes
- Spiroindoles (e.g., derquantel) - effective against a variety of nematodes including those resistant to other anthelmintic classes
- Artemisinin shows anthelmintic activity.
The ability of parasites to survive treatments that are generally effective at the recommended doses is a major threat to the future control of worm parasites in small ruminants and horses. This is especially true of nematodes, and has helped spur development of aminoacetonitrile derivatives for treatment against drug-resistant nematodes, as well as exploration of doxycycline to kill their endosymbiotic Wolbachia bacteria.
The resistance is measured by the "fecal egg count reduction" value which varies for different types of helminths.
Treatment with an antihelminthic drug kills worms whose phenotype renders them susceptible to the drug, but resistant parasites survive and pass on their "resistance" genes. Resistant varieties accumulate, and treatment failure finally occurs.
- WHO (2006). Preventive chemotherapy in human helminthiasis: coordinated use of anthelminthic drugs in control interventions: a manual for health professionals and programme managers (PDF). WHO Press, World Health Organization, Geneva, Switzerland. pp. 1–61. ISBN 9241547103.
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- "Helminth control in school-age children" (PDF). World Health Organisation. 2011. Retrieved 28 July 2015.
- Hagel I, Giusti T (October 2010). "Ascaris lumbricoides: an overview of therapeutic targets". Infect Disord Drug Targets. 10 (5): 349–67. doi:10.2174/187152610793180876. PMID 20701574.
new anthelmintic alternatives such as tribendimidine and Nitazoxanide have proved to be safe and effective against A. lumbricoides and other soil-transmitted helminthiases in human trials.
- Shoff WH (5 October 2015). Chandrasekar PH, Talavera F, King JW (eds.). "Cyclospora Medication". Medscape. WebMD. Retrieved 11 January 2016.
Nitazoxanide, a 5-nitrothiazole derivative with broad-spectrum activity against helminths and protozoans, has been shown to be effective against C cayetanensis, with an efficacy 87% by the third dose (first, 71%; second 75%). Three percent of patients had minor side effects.CS1 maint: uses editors parameter (link)
- Veterinary Parasitology
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