Cholinergic Antagonists Flashcards
Cholinergic Antagonists Types
Antimuscarinic / Ganglionic blockers / Neuromuscular blockers
Atropine
Competitive Antimuscarinic
Atropine Eye Actions
Mydriasis + Cycloplegia + unresponsiveness to light
Atropine Uses
Ophthalmic examinations , sinus bradycardia , urinary urgency/ enuresis , antidote for AchE poisoning
Atropine GI effects
Antispasmodic , antisecretory ( saliva , lacrimation , sweat) , decreases bladder hypermotility (urinary retention)
Atropine CVP effects
Tachycardia , bronchodilation (reduced secretions)
Atropine CNS effects
Excitatory , restlessness , irritability
Atropine Adverse Effects
urinary retention , mydriasis , constipation , xerostomia
Atropine CI
Glaucoma , prostate enlargement
Scopolamine
Oral Antimuscarinic
Scopolamine Uses
helps with motion sickness (sedation + dryness)
Ipratropium
Inhaler ; antimuscarinic
Ipratropium Uses
Asthma & COPD
Tropicamide
topical antimuscarinic
Tropicamide Uses
Mydriasis (short duration)
Nicotine, Hexamethonium, Tubocurarine
Ganglionic blockers ( Nn-R)
Nicotine, Hexamethonium, Tubocurarine
MOA
Causes stimulation then paralysis of all ganglia
Succinylcholine
Neuromuscular Blocking Drug - Depolarizing Agonist
Succinylcholine MOA
Acts like Ach (longer action) ; depolarization , transient fasciculations , flaccid paralysis , repolarization , desensitized receptors.
Succinylcholine Uses
Endotracheal intubation (muscle relaxation)
Succinylcholine Adverse Effects
Hyperthermia (halothane) , apnea (AchE def.) , hyperkalemia (burn)
Diazepam & Dantrolene
Neuromuscular Blocking Drugs (muscle relaxants)
Tubocurarine/Pancuronium
Non-Depolarizing Antagonists (Competitive)
Non-Depolarizing Antagonists MOA
Act on Nm to prevent binding of ACh : inhibit depolarization & contraction (use neostigmine to counteract this effect)
