Ketoconazole, an azole antifungic drug wich is already in the market has also been demonstrated to be active against Trypanosoma Cruzi experimental infections. In this paper we confirmed the drug effect and investigated its range of activity different T.cruzi strains naturally resistant or susceptible to both standard drugs Nifurtimox and Benznidazole plus Lovastatin (an inhibitor of sterol synthesis), wich has an antiproliferative effect against T. cruzi in vitro, failed to enhance the suppressive of Ketoconazole displayed when administered alone to infected mice. Finally, administration in chronic chagasic patients of Ketoconazole at doses used in the treatment of deep mycosis also failed to induce cure as demonstrated by parasitological and serological tests. The strategy of identify and test drugs wich are already in the market and fortuitously are active against T.cruzi has been discussed.