Leishmaniasis is a disease caused by protozoan parasites of the genus Leishmania. The treatment of intracellular infections such as leishmaniasis is often challenging due to limited drug access to infected cells and the development of drug resistance. Therefore, the development of new antileishmanial compounds is essential. Paromomycin sulphate (PM) has shown promise as an antileishmanial drug, and one way to enhance its effectiveness is through appropriate delivery systems. Solid lipid nanoparticles (SLN) are being explored as a potential delivery system for PM, as they offer advantages over other colloidal carriers. In a recent study, PM was loaded into solid lipid nanoparticles (PM-SLN) and its oral effectiveness was evaluated in treating Leishmania (L.) major-infected mice. The study measured footpad swelling, quantified parasite load through real-time PCR and assessed levels of cytokines such as interleukin-4 (IL-4) and gamma interferon (IFN-c), nitric oxide (NO) and Arginase (ARG). Overall, the study demonstrated that oral administration of the PM-SLN formulation is safe and effective in treating leishmaniasis. The SLN in the PM-SLN compound improved the killing of parasites by PM and stimulated a Th1 immune response, indicating its potential as a treatment for leishmaniasis.