Preliminary screening of antifilarial activity of levamisole and amodiaquine on Wuchereria bancrofti.

A single dose of levamisole of 3 mg/kg had a marked microfilaricidal effect in some persons harbouring Wuchereria bancrofti, but there was considerable variation in the response. In some cases blood examinations for microfilariae remained negative or at a low level for several months. Persons with high pretreatment microfilaraemias responded less to therapy than did those with low counts. The main side-reaction to levamisole was fever, which began six to eight hours after treatment. Combined DEC-levamisole therapy appears to have no advantage over the use of DEC alone. Amodiaquine in a total dose of 40 mg/kg appears to be macrofilaricidal, but because of the slight possibility of blood dyscrasias, mass chemotherapy with this dosage could not be recommended. Some amodiaquine congeners shown to be effective in experimental infections against adult filarial worms may prove to have a higher chemotherapeutic index than amodiaquine against W. bancrofti in man.