What is a common and serious potential side effect of the medication pyridostigmine?

Pyridostigmine is a medication often used to treat myasthenia gravis, a neuromuscular disorder, by inhibiting the enzyme acetylcholinesterase. This inhibition increases the concentration of acetylcholine at the neuromuscular junction, enhancing communication between nerves and muscles.

A significant and serious potential side effect of pyridostigmine is cholinergic crisis. This occurs when there is an overabundance of acetylcholine due to excessive inhibition of acetylcholinesterase, leading to overstimulation of acetylcholine receptors. Symptoms of a cholinergic crisis can include muscle weakness, increased salivation, sweating, gastrointestinal distress, bradycardia, and potentially respiratory distress due to muscle paralysis. This condition necessitates immediate medical attention.

While respiratory depression and hypertensive crisis can be serious complications in various medical contexts, they are not directly caused by pyridostigmine. Serotonin syndrome is related to medications affecting serotonin levels and is not a known side effect of pyridostigmine treatment. Understanding the distinction between these potential scenarios underscores the importance of dosing and monitoring when using cholinergic medications like pyridostigmine.