Used in research to simulate the action of acetylcholine, particularly in studies involving cholinergic receptors. It is valuable in pharmacological experiments to understand the function of muscarinic receptors in smooth muscle, heart, and glandular tissues. Due to its resistance to degradation by acetylcholinesterase, it produces prolonged cholinergic effects, making it useful for testing receptor responses without rapid signal termination. Also employed in ophthalmic studies to induce miosis during eye surgery or in glaucoma research.