<prompt> Drug of choice in the treatment of onchocerciasis isDECIvermectinKetoconazoleCotrimoxazole  <response>: B Ivermectin Ivermectin, a semisynthetic macrocyclic lactone active against microfilariae, is the first-line agent for the treatment of onchocerc asis. It is given orally in a single dose of 150 pgkg, either yearly or semiannually. 