Pharmacology Anthelmintic Agents Practice Test

Ivermectin primarily acts by enhancing the release of gamma-aminobutyric acid (GABA), which is crucial for its antiparasitic effects. GABA is an important inhibitory neurotransmitter in both vertebrates and invertebrates. In the context of parasites, the increased GABA levels cause paralysis of the neuro-muscular system, leading to the death of various parasitic nematodes and ectoparasites.

This mechanism makes Ivermectin effective against a wide range of parasites by disrupting their ability to move and feed. The drug binds to glutamate-gated chloride channels, which are not present in mammals, providing a selective toxicity that allows it to target parasites while minimizing effects on human systems.

The other options reflect mechanisms that do not accurately describe the action of Ivermectin, as the drug does not primarily inhibit protein synthesis, alter osmotic balance, or interfere directly with glucose uptake. Therefore, the unique action of Ivermectin on the GABAergic system is what underpins its effectiveness as an anthelmintic agent.