Neostigmine is used in the following except -
Ans. is 'd' i.e., Glaucoma ITSF.S OF ANTICHOLINESTERASESNeostigmineMyasthenia graviso In myasthenia gravis there is marked depletion of nicotine receptors at neuromuscular junction due to formation of autoantibodies against these receptors.o Neostigmine (or Pyridostigmine) helps by increasing the concentration of AcH at neuromuscular junction - AcH act on receptors over a large areas,o Neostigmine also has a direct action on Nm receptorsCurare poisoningo d-tubocurarine (active component of curare) is a competitive Nm blockers. Neostigmine is used to reverse the action of competitive Nm blockers.Postoperative parolytic ileus.o AcH (which is increased by Neostigmine) increases parastalasis due to increased motor activity.Cobra biteo Cobra venom has curare like neurotoxin.o Neostigmine acts in similar fashion as for reversal of competitive Nm blockers.Atony of bladdero AcH (which is increased by neostigmine) stimulate detrusor and relaxes trigone --> Micturation.PhvsostigmineGlaucomao It increases the concentration of AcH which causes contraction of smooth muscle of iris and ciliary muscles - the iris is pulled away from angle of anterior chamber and the trabecular mashwork at the base of ciliary' muscle is opened -| aqueus outflow into the canal of Schlemm from anterior chamber - | intraocular tension.o A more recent use of anticholinesterase drugs has been to improve cognitive function in patients with Alzheimer's disease - Drugs used are Donepezil and rivastigmine.About other optionsOption 'c'o Excessive dosing with an anticholinesterase can actually worsen the muscle weakness in mysthenics if the accumulation of acetylcholine at neuromuscular junction is sufficient to cause persistent depolarization (depolarizing block)--> cholinergic crisis.o Neostigmine wrill further increase the concentration of AcH - worsening of cholinergic crisis.Option 'd'o Neostigmine is not used in arrhythmias
Myasthenia gravis
Cobra bite
Atony of bladder
Glaucoma
Cholinergic System