In the absence of effective vaccines, treatment and prophylaxis of parasitic nematode infections of humans and animals relies on anthelmintic drugs. Emodepside is a more recently introduced cyclooctadepsipeptide anthelmintic drug that breaks resistance to the classical anthelmintics. Emodepside has a novel mode of action involving a calcium-activated potassium channel, SL0-1, and latrophilin (lat) receptor in Caenorhabditis elegans. The purpose of our experiments was to examine the mechanisms of action of emodepside in the parasitic nematode, Ascaris suum. We used electrophysiological techniques to record emodepside effects in A. suum muscle and performed molecular biology experiments to investigate the expression of emodepside target genes.