Selamectin, a semi-synthetic macrocyclic lactone, is a potent parasiticide and anthelminthic. Selamectin activates glutamate-gated chloride channels in neurons and pharyngeal muscles to prevent heartworm, Lymphatic filariae, and nematode infection. Selamectin is also a potent P-glycoprotein substrate and a P-glycoprotein inhibitor with an IC50 of 120 nM[1][2].
