Background:

Neostigmine bromide is a reversible inhibitor of acetylcholinesterase.[1]

AChE (acetylcholinesterase) is a hydrolase that hydrolyzes the neurotransmitter acetylcholine at the neuromuscular junction and cholinergic synaspe. It terminates the signal transductions and plays a role in neuronal apoptosis.

Neostigmine bromide is a quaternary amine that blocked cholinesterase activity to extend and enhance the muscarinic and nicotinic effects of acetylcholine. It is implicated for the treatment of primary open-angle glaucoma, postoperative urinary retention, paralytic ileus, myasthenia gravis etc. It is also reported to be an adjuvant to local anaesthetics and opioids for post-surgical pain after gynaecological or abdominal surgery. [1]

Reference:
[1] El-Kosasy AM, Nebsen M, Abd El-Rahman MK, Salem MY, El-Bardicy MG.  Comparative study of 2-hydroxy propyl beta cyclodextrin and calixarene as ionophores in potentiometric ion-selective electrodes for neostigmine bromide.  Talanta. 2011 Aug 15;85(2):913-8.