In the current study, we evaluated the mechanism of action of miltefosine, which is the first effective and safe oral treatment for visceral leishmaniasis, in
Leishmania amazonensis
promastigotes. Miltefosine induced a process of programmed cell death, which was determined by the externalization of phosphatidylserine, the incorporation of propidium iodide, cell-cycle arrest at the sub-G
0/G
1 phase and DNA fragmentation into oligonucleosome-sized fragments. Despite the intrinsic variation that is detected in
Leishmania spp, our results indicate that miltefosine causes apoptosis-like death in
L. amazonensis promastigote cells using a similar process that is observed in
Leishmania donovani
.