Revista do Instituto de Medicina Tropical de São Paulo
versión On-line ISSN 1678-9946
BARBOSA, Carlos Augusto Lopes; CAMPOS, Dulcinéa Maria Barbosa y OLIVEIRA, Jayrson Araújo de. ASSESSMENT OF IVERMECTIN THERAPEUTIC EFFICACY ON THIRD-STAGE LARVAE OF Lagochilascaris minor IN MICE EXPERIMENTALLY INFECTED. Rev. Inst. Med. trop. S. Paulo [online]. 1998, vol.40, n.3, pp.137-144. ISSN 1678-9946. http://dx.doi.org/10.1590/S0036-46651998000300002.
In this study we evaluated the potential action of ivermectin on third-stage larvae, both at migratory and encysted phases, in mouse tissues after experimental infection with Lagochilascaris minor. Study groups I and II consisted of 120 mice that were orally administered 1,000 parasite eggs. In order to assess ivermectin action upon migratory larvae, group I (60 mice) was equally split in three subgroups, namely I-A, I-B, and I-C. On the 7th day after inoculation (DAI), each animal from the subgroup I-A was treated with 200 µg/Kg ivermectin while subgroup I-B was given 1,000 µg/Kg, both groups received a single subcutaneous dose. To assess the drug action on encysted larvae, group II was equally split in three subgroups, namely II-A, II-B, II-C. On the 45th DAI each animal was treated with ivermectin at 200 µg/Kg (subgroup II-A) and 1,000 µg/Kg (group II-B) with a single subcutaneous dose. Untreated animals of subgroups I-C and II-C were used as controls. On the 60th DAI all animals were submitted to larva search. At a dose of 1,000 µg/Kg the drug had 99.5% effectiveness on third-stage migratory larvae (subgroup I-B). Ivermectin efficacy was lower than 5% on third-stage encysted larvae for both doses as well as for migratory larvae treated with 200µg/Kg.
Palabras clave : Ivermectin; Lagochilascaris minor; Third-stage larvae.