What is a potential side effect of excessive Edrophonium use?

Edrophonium is a short-acting reversible inhibitor of the enzyme acetylcholinesterase, which leads to increased levels of acetylcholine at the neuromuscular junction and other cholinergic sites. While this can be beneficial for diagnosing conditions like myasthenia gravis by temporarily increasing muscle strength, excessive use can lead to overstimulation of cholinergic receptors.

A potential side effect of excessive Edrophonium use is a cholinergic crisis. This condition is characterized by an overwhelming action of acetylcholine in the body, resulting in symptoms such as muscle weakness, excessive salivation, lacrimation, urination, diarrhea, gastrointestinal distress, and bradycardia — all due to exaggerated parasympathetic activity. It can lead to respiratory failure due to severe muscle weakness, especially involving the diaphragm.

This side effect emphasizes the importance of careful dosing and monitoring in patients receiving Edrophonium to prevent oversaturation of the cholinergic system, which can lead to serious complications.