Edrophonium is a quaternary ammonium ion, specifically N-ethyl-N,N-dimethylanilinium with a hydroxy group at one meta position. It is a reversible cholinesterase inhibitor with a rapid onset (30-60 seconds) and short duration of action (5-15 minutes). The chloride salt is used diagnostically in myasthenia gravis and to differentiate between under- or over-treatment with other anticholinesterases. It also serves as a reversal agent for neuromuscular blockade in anaesthesia and as an antidote for tetrodotoxin poisoning. It functions as a cholinesterase inhibitor, diagnostic agent, and antidote, and is a member of phenols.
