About Neostigmine Para-sympathomimetic, a reversible Anticholinesterase, In Myasthenia gravis treatment,an adjunct in general anaesthesia, Curare antagonist. Mechanism of Action of Neostigmine It inhibits the destruction of acetylcholine by cholinesterase (by competing with acetylcholine for attachment to acetyl cholinesterase) and thus prolongs and intensifies the physiological actions of acetylcholine. It facilitates transmission of impulses across the myoneural junction by increasing the amount of acetylcholine at the nerve endings. Increased levels of acetyl choline allow the remaining receptors to function more efficiently. It also has direct effects on skeletal muscle fibres. The anticholinesterase actions of Neostigmine are reversible. Neostigmine is used in the treatment of myasthenia gravis and has been used as an alternative to Edrophonium in the diagnosis of myasthenia gravis.