The preparation and physico-chemical characterization of lyophilized polyisohexylcyanoacrylate nanoparticles loaded with dehydroemetine (DHE) for the treatment of visceral leishmaniasis disease is described. The resulting formulation was found to efficiently absorb DHE and gave very reproducible preparations with regard to the size and drug adsorption rate. Stability has been confirmed for at least 24 months. The acute toxicity of DHE was reduced in intravenous administration by its association with nanoparticles. Data concerning tissue distribution in mice showed that DHE nanoparticles were rapidly cleared from the blood stream and that they mainly concentrated in the reticuloendothelial system. Furthermore, DHE linkage to the carrier reduced the cardiac concentrations of the drug.