Pyrantel pamoate is a luminal anthelmintic that acts as a depolarizing neuromuscular blocking agent in susceptible nematodes. It functions as a nicotinic acetylcholine receptor agonist and cholinesterase inhibitor, producing sustained contraction and spastic paralysis. Immobilized worms lose their grip on the intestinal mucosa and are expelled by normal peristalsis without significant systemic absorption in humans.