Antihelminthic activity

Pyrantel pamoate (9.125), a tetrahydropyrimidine derivative, is a broad-spectrum antihelminthic active against pinworm and hookworm. This drug causes release of acetylcholine in the worm, producing stimulation and paralysis, leading to expulsion from the host s intestinal tract. 

Mebendazole is a synthetic benzimidazole that has a wide spectrum of antihelminthic activity and a low incidence of adverse effects. 

Pyrantel pamoate is a broad-spectrum antihelminthic highly effective for the treatment of pinworm, ascaris, and Trichostrongylus orientalis infections. It is moderately effective against both species of hookworm. It is not effective in trichuriasis or strongyloidiasis. Oxantel pamoate, an analog of pyrantel not available in the USA, has been used successfully in the treatment of trichuriasis the two drugs have been combined for their broad-spectrum antihelminthic activity. 

In a boiling mixture of nitric (d 1.50) and concentrated sulfuric acids 2-chloroben-zimidazole gives 2-chloro-5,6-dinitrobenzimidazole in a 75-80% yield [67], In analogous conditions, benzimidazole and 2-alkyl substituted benzimidazoles are also transformed into 5,6-dinitro derivatives however, in this case simultaneous formation of 4,6-dinitro isomers, which can be separated by fractional crystallization, has been fixed [48, 68], 5(6)-Nitro-2-heterylbenzimidazoles (thiazolyl-4-, furyl-4-, and pyrrolyl-4-) having antihelminthic activity were obtained by nitration with sulfuric-nitric mixture on cooling [69],... 

The newer broad-spectrum benzimidazoles have a wide spectrum of antihelminthic activity, killing larval and adult... 

Levamisole has also an immunostimulant activity [63] and its antihelminth activity in part may be mediated through its action on the immune system. 

Answer D. Praziquantel is the drug of choice for treatment of all fluke (trematode) infections and most tapeworm (cestode) infections. Its antihelminthic action derives from an increase in membrane permeability to Ca, which results in contraction, followed by paralysis, of worm musculature. Mebendazole also has antihelminthic activity, hut it is restricted to the nematodes. The other drugs listed are antiprotozoals. 

Bacitracin is mainly used for topical application. A great variety of ointments, solutions, troches and tablets are available for local application. For broadening of the antimicrobial spectrum it is very often combined with other antibiotics such as neomycin, penicillin, tyrothricin and polymixin. Topical administration is used against infections of the skin, eye, ear and throat, with little incidence of sensitization. Good results have been obtained in the prophylactic and active treatment of infected burns - . Inhalation has been reported for susceptible respiratory tract infections. Bacitracin appears to have some antihelminthic activity. ... 

Albendazole is a broad-spectrum antihelminthic drug used to treat the tropical parasitic disease, human neurocysticercosis. Albendazole contains a sulfur group that is subject to oxidation to an active sulfoxide metabolite. The S-oxide metabolite forms a center of asymmetry at the sulfur atom, thus conferring chirality to the molecule. Albendazole sulfoxide steady-state pharmacokinetics have been studied in 18 patients with confirmed active neurocysticercosis after repeated dose administration of 5mg/kg thrice daily for 8 days [44]. A high degree of stereoselectivity was observed in the plasma concentrations of the sulfoxide metabolite, with Cmax and AUCss (-I-) (—) ratios of 5.5 and 9.2, respectively. It is not known if there is stereoselectivity in the antihelminthic activity of the (-1-)- and (—)-sulfoxide metabolites of albendazole. 

The essential oils possess antimicrobial and antihelminthic activities. The methanolic extracts from the leaves and its alkaloids vasicine and vasicinol showed sucrase inhibitory activity with sucrose as a substrate. The extract of A. vasica showed antioxidant and radical scavenging activities, and anticestodal efficacy.The alkaloid fractions of the methanolic extract showed anti-inflammatory and antibacterial activities. The leaf powder ex-... 

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