Fido's Closasole Broadspectrum Wormer For Dogs & Cats is a top-quality wormer oral treatment that aids in treating roundworms, hookworms, whipworms, and tapeworms. Fidos Closasole Broad Spectrum Wormer For Dogs & Cats is made up of two key ingredients; Niclosamide and Levamisole. While Niclosamide is effective at effectively treating tapeworms, Levamisole is an antiparasitic ingredient that suppresses the enzyme activity in the worm’s muscle, causing paralyses before eliminating them completely.