Selamectin

Selamectin is the active ingredient in Revolution, a topical insecticide and antihelminthic used on dogs and cats. It controls fleas, heartworm, hookworms, roundworms, and ear mites. Because it is a heartworm preventative, selamectin requires a veterinarian's prescription.

Selamectin works by replacing glutamate which normally interacts with receptors that open chloride channels at muscle synapses found in parasites. Unlike glutamate, selamectin activates the chloride current without desensitization, thereby producing prolonged hyperpolarization and impaired muscle contraction.