Ivermectin immobilizes affected organisms by inducing tonic paralysis of the musculature of the parasites by binding to the chloride ion channels of nerve or muscle cells.  Ivermectin is a type of anthelmintic, which is a medicine that kills parasites such as worms. It works by interfering with the nerve and muscle functions of parasitic worms. It paralyzes the parasites or inactivates their gut, which kills them.