By interfering with the breakdown of acetylcholine,<unk>  indirectly stimulates both nicotinic and muscarinic receptors. Unlike physostigmine,<unk>  has a quaternary nitrogen; hence, it is more polar. It does not cross the blood–brain barrier and enter the CNS. However, it does cross the placenta. Its effect on skeletal muscle is greater than that of physostigmine.<unk>  has moderate duration of action – usually two to four hours.<unk>  binds to the anionic and ester site of acetylcholinesterase, which blocks the enzyme from breaking down the acetylcholine molecules before they reach the postsynaptic membrane receptors. This allows for the threshold to be reached so a new impulse can be triggered in the next neuron. In myasthenia gravis there are too few acetylcholine receptors so with the acetylcholinesterase blocked, acetylcholine can bind to the few receptors and trigger a muscular contraction.
Neostigmine
Physostigmine
Pyridostigmine
Suxamethonium chloride
Atropine
Rocuronium bromide
Alcuronium chloride
Gantacurium chloride