Twenty-four dogs naturally infected by Leishmania spp. were treated with 4 different protocols using meglumine antimoniate and allopurinol. One of the protocols was never proposed previously. Aiming to compare the efficacy of the different treatments the clinical-pathological remission and the disease free interval time (TLR) were evaluated. Treated dogs were monitored for 1 year and, in absence of relapses, the disease free interval time was postponed to the last available follow up. Seven dogs showed relapses during the year, all of them were treated with meglumine antimoniate alone. In the group of dogs treated with the combination of drugs no relapses were registered in the year of monitoring and the TLR reached up to 65 months. Our results showed that this combination represents the best choice to treat canine leishmaniosis compared to the other protocols.