Cholinergic Medications

Excerpt

Cholinergic medications are a category of pharmaceutical agents that act upon the neurotransmitter acetylcholine, the primary neurotransmitter within the parasympathetic nervous system (PNS). There are two broad categories of cholinergic drugs: direct-acting and indirect-acting. The direct-acting cholinergic agonists work by directly binding to and activating the muscarinic receptors. Examples of direct-acting cholinergic agents include choline esters (acetylcholine, methacholine, carbachol, bethanechol) and alkaloids (muscarine, pilocarpine, cevimeline). Indirect-acting cholinergic agents increase the availability of acetylcholine at the cholinergic receptors. These include reversible agents (physostigmine, neostigmine, pyridostigmine, edrophonium, rivastigmine, donepezil, galantamine) and irreversible agents (echothiophate, parathion, malathion, diazinon, sarin, soman). This activity reviews the mechanism of action, adverse event profile, toxicity, dosing, pharmacodynamics, and monitoring of cholinergic agents, which is a topic of significant complexity and with far-reaching clinical implications, as is pertinent for members of the interprofessional team in dealing with the effects of these agents, both therapeutic and toxic.