Efficacy of mebendazole and levamisole, alone or in combination, for soil-transmitted helminthiasis

Background The World Health Organization (WHO) recommends four, single-dose drugs (albendazole, levamisole, mebendazole, and pyrantel pamoate) for management of soil­transmitted helminthiasis (STH). Previous studies have shown varied and inconsistent outcomes of these STH treatments. Objective To compare the efficacy of mebendazole and levami­sole, alone or in combination, for the treatment of STH. Methods An open randomized controlled trial was conducted in Secanggang, North Sumatera from August to October 2009. School-aged children with STH infection were randomized into three groups. Group I received a single dose of mebendazole (500 mg); group II received a single dose of levamisole (2.5 mg/kg); and group III received a single dose of mebendazole-levamisole combined. Stool samples were collected at baseline, and the 1st, 2nd, 3rd, and 4th weeks after treatment and examined by the Kato-Katz technique. Statistical analyses were Kruskal-Wallis test for cure rate and Analysis of Variance (ANOVA) test for egg reduction rate. Results STH was diagnosed in 197 children with the following parasite species: Ascariasis (96 children, 48.7%), Trichuriasis (58 children, 29.4%), and mixed infection (43 children, 21.8%). We found no hookworm infection in any of our subjects. Groups I and III had significantly higher efficacy (P=0.0001) against STH (egg reduction rate 99.3% and 99.9%; cure rate 92.2% and 98.4%, respectively) at 4th week of treatment. Conclusion A single dose of mebendazole alone and combined with levamisole have better efficacy compared to a single dose of levamisole for the treatment of STH. The highest efficacy of these treatments is noted at the 4th week after drug administratio