Anthelmintics or antihelminthics are a group of antiparasitic drugs that expel parasiticworms (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.
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 antibiotics use against their endosymbiotic Wolbachia bacteria.
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 finally treatment failure occurs.
^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. PMID20701574. 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)
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