RESUMEN
We have studied the effectiveness of pharmacologic prophylaxis of experimental peritoneal hydatidosis. Mice (n = 140, divided in ten groups) suffered intraperitoneal contamination with protoscoleces of E. granulosus from sheep. Each group received different treatment (mebendazole, praziquantel, or both), in three different schedules (during 3 days before contamination, during 7 days after contamination, or both before and after Mebendazole 150 mg/kg-day), praziquantel (25 mg/kg-day) were given in three daily doses. Mice were sacrificed six months later and the number and type of existing peritoneal cysts was recorded. Prophylaxis prior to contamination was shown ineffective. Early treatment greatly decreased the severity of the peritoneal hydatidosis. The administration of the drug before and after contamination, did not improve the results obtained when the drug was given after contamination. Both mebendazole and praziquantel were effective, though the former obtained better results. The association of both drugs does not improve the results obtained with mebendazole alone. These experimental results recommend the early use of mebendazol or praziquantel after open surgery for hydatidosis, in order to prevent the occurrence of secondary peritoneal hydatidosis.