Pharmacology - Neostigmine

Pharmacology -  Neostigmine 
Actions
Acts as parasympathomimetic: increased peristalsis; increased secretions; bradycardia; bronchoconstriction; and lowered intraocular pressure. When the neuromuscular junction is affected, fasciculation and increased twitch tension are observed. CNS – agitation and dreaming are symptoms.

Mode of Action 
By inhibiting acetylcholinesterase in a reversible manner, the breakdown of acetylcholine at cholinergic nerve terminals is reduced, which in turn amplifies the activity of the transmitter. Interacts with the esteratic and anionic sites that are present in the enzyme. Carbamylation has occurred in the esterase.


Absorption / Distribution / Elimination  
In order to reverse the neuromuscular block, it is administered intravenously. For myasthenia gravis, it is used orally. It is primarily ionized, which results in a low oral bioavailability and a limited capacity to penetrate the blood–brain barrier. The half-life is one hour.


Use in clinical settings 
Myasthenia gravis is a condition. Inversion of a neuromuscular block that does not depolarize the muscle. Post-operative urine retention is occurring. Myasthenia gravis is treated with pyridostigmine. Physostigmine helps treat glaucoma.


Adverse Effects 
May make asthma symptoms worse. Atropine has the ability to lessen the effects of unwanted parasympathomimetic activities.