Fikireselassie Samuel.pdf - Addis Ababa University

educe morbidity and avoid mortality associated with the disease (Albonico et al., 2008). The
four anthelminthics recommended by the WHO against soil-transmitted helminths are:
mebendazole (MBD), albendazole (ALB), levamisole and pyrantel. While ivermectin is not
recommended for the treatment of human STH, except for strongyloidiasis, it has activity against
ascariasis, hookworm and trichuriasis albeit less than the 4 drugs listed above. However, in the
new perspective of preventive chemotherapy this drug requires attention as it is used for
onchocerciasis and in "combination treatment" for lymphatic filiariasis, and thus will have
collateral effects in STH co-infection.
The benzimidazoles (BZ) – MBD and ALB - are the most frequently used anthelminthics to treat
infections with STHs (Montresor et al., 2002). While both show broad-spectrum anthelminthic
activity, for hookworms a single dose of ALB is more effective than mebendazole (Bennett and
Guyat, 2000).
Although both ALB and MBD are deemed broad-spectrum anthelminthic agents, important
therapeutic differences affect their use in clinical practice. Both agents are effective against
Ascaris in a single dose. However, in hookworm, a single dose of mebendazole has a low cure
rate and albendazole is more effective (Albonico et al., 2002). Conversely, a single dose of
albendazole is not effective in many cases of trichuriasis (Adams et al., 2004). For trichuriasis
and hookworm infection, several doses of benzimidazole anthelminthic drugs are commonly
needed. Another important difference between the two drugs is that mebendazole is poorly
absorbed from the gastrointestinal tract so its therapeutic activity is largely confined to adult
worms. Albendazole is better absorbed, especially when ingested with fatty meals, and the drug
is metabolized in the liver to a sulphoxide derivative, which has a high volume of distribution in
the tissues (Dayan et al., 2003). For this reason, albendazole can be used for the treatment of
disorders caused by tissue emigrating larvae such as visceral larva migrans caused by Toxocara
canis.
A single oral dose of 400mg Albendazole is highly effective against Ascaris lumbricoides with
cure rates (CR) and egg reduction rates (ERR) between 92% and 100%. The drug is effective
against hookworms (CR 57%-95% and ERR 79%-99%) and has usually been shown to be more
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