Levo-Tetramisole

Angiostrongylosis - Levo-tetramisole has been shown to effect reductions in numbers of migrating larvae of Angiostrongylus cantonensis in rats l but neither it nor thiabendazole, the only other drug shown to be active in this infection, is reported to have been tested in man. 

Ascariasis - Levo-tetramisole has also been shown to be more potent than... 

The racemic DL-tetramisole and its levo-isomer, levamisole, constitute the best-known members within this group of drugs (Fig. 4.2). Since the anthelminthic activity of tetramisole, which was first marketed in 1966, resides almost entirely in its levo-isomer, levamisole rather than the parent tetramisole is the drug currently used in most countries. 

Some antiparasitic drugs, notably the macrocyclic lactones, have already been addressed in Chapter 6. This chapter will examine the toxic effects of other compounds that are widely used, or have been used, as antiparasitic drugs in animals. In Europe and elsewhere, the main anthelmintic drugs are the benzimidazoles and levamisole. The major benzimidazole drugs are thiabendazole, albendazole, fenbendazole, flubendazole, mebendazole, oxfendazole, oxiben-dazole, triclabendazole and albendazole sulphoxide (ricobendazole, albendazole oxide). Febantel and netobimin are two prodrugs that in vivo are converted to fenbendazole and albendazole, respectively. Levamisole is the levo ( ) isomer of (dextro isomers. Tetramisole has been superseded by levamisole. These and some other antiparasitic drugs are discussed in this chapter. 

Although the dextro and levo forms are comparable in toxicity for mice, the levo isomer shows hi er biological activity.to vitro studies indicate that tetramisole causes muscular paralysis in ascaris worms. Specifically, the drug inhibits succinate dehydrogenase activity of the worm. The levo isomer is a more potent enzyme inhibitor than the dextro isomer or the racemic mixture. 

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