Recently, the incidence of American Cutaneous Leishmaniasis (ACL) has been grown in Latin America, especially in Brazil, where from 1980 to 2005, 605,062 cases were recorded. The drug glucantime®, whose active principle is the meglumine antimoniate (or meglumine antimonate) is used in the treatment of leishmaniasis. Its toxicity is due mainly to the presence of antimony in its structure. Therefore, it is crucial to determine the safe dose levels of this drug in the treatment.