Echinococcus multilocularis: in vivo results of therapy with albendazole and praziquantel.

The effects of albendazole and praziquantel on the growth of Echinococcus multilocularis were studied in cotton rats. Albendazole (20 and 50 mg/kg) reduced parasite weight and increased the length of survival of infected animals but viable infection was present after treatment. In an in vitro system albendazole sulphoxide entered cysts of E. multilocularis passively. Praziquantel 100 mg/kg was ineffective but 500 mg/kg significantly inhibited growth. A combination of albendazole and praziquantel was no more effective than either agent alone.

Comparison of albendazole, mebendazole and praziquantel chemotherapy of Echinococcus multilocularis in a gerbil model.

The efficacy of albendazole (50 mg/kg/d), mebendazole (50 mg/kg/d) and praziquantel (500 mg/kg/d) against established intraperitoneal infections of Echinococcus multilocularis in gerbils was compared by monitoring parasite weight and making ultrastructural observations on treated and untreated material. Praziquantel was the most active protoscolicidal agent, reducing protoscolex viability to less than 2%, although it did not inhibit cyst growth. Albendazole was the most effective agent in reducing cyst growth and was, when compared with other regimes significantly more effective than mebendazole (p less than 0.05), praziquantel (p less than 0.01) or untreated controls (p less than 0.01).