Effect of mebendazole and metronidazole in the survival of hydatid protoscolices of echinococcus granulosus in vitro and in viro

ABSTRACT

The effect of metronidazole and mebendazole on the survival of protoscolicies of Echinococcus granulosus was studied. In vitro, a concentration of 10 ug/ml of either drug in hydatid fluid significantly reduced the survival of protoscolicies. This effect was marked 4-5 days after incubation. In vivo, in mice, the i.p. administration for 10 days of either metronidazole [100 mg/kg/day] or mebendazole [10 mg/kg/day] or both drugs together inhibited the development of hydatid cysts in mice challenged with protoscolicies suspension [about 4000 scolex/ml] at the beginning of the experiment. Both the number and size of cysts that resulted were reduced, but cyst development was not abolished. The combination of both drugs showed some synergism in reducing cyst size but not number, when compared to animals receiving either drug alone. The daily administration of mebendazole in a dose of 50 mg/kg i.p. for 10 days completely prevented the development of abdominal hydatid cysts after challenge with protoscolicies suspension at the beginning of treatment. It is concluded that metronidazole could inhibit the survival of E. granulosus protoscolicies both in vitro and in vivo in mice in a manner comparable to mebendazole and may even be synergistic with it