Parasympathetic System - Direct acting Flashcards
Parasympathomimetics
Drugs that stimulate parasympathetic nervous system through modulation of cholinergic receptors or ACh.
what are the 3 muscarinic parasympathomimetics?
Acetylcholine
Muscarine
Policarpine
You would like to perform ocular surgery on a patient? Which drug would you use and why?
Acetylcholine to obtain miosis. It does however have bradycardia and hypotension as side effects.
A patient gets mushroom poisoning from muscarine ingestion. Which side effects would he present with?
SLUDGE BBB/ DUMBELLS
What is policarpine’s clinical indication?
It can be used to treat glaucoma and ocular hypertension by allowing excess fluid to drain from the eye. As a side effect it causes eye spasms.
What is the action of direct nicotinic drugs on recepetors?
Direct interaction with cholinergic receptors to promote parasympathetic activity
In the case of cessation of smoking would you use Nicotine or Varenicline drugs?
Nicotine because it’s side effects include allergic reactions, coughing and increased salivation whereas Varenicline induces vomiting, causes nausea and there is increased risk of suicidal ideation.
A patient is about to undergo surgery. Which drug would you administer and why?
syn. succinylcholine because it is a depolarizing neuromuscular blockade. Depolarizing neuromuscular blockers are drugs used to induce anesthesia and relax skeletal muscles (paralysis) during intubation, mechanical ventilation, and surgical procedures
How do indirect cholinesterases work?
Drugs that decrease the ACh metabolism
They blocks AChE-mediated metabolism
of ACh resulting in increased synaptic ACh, boosting cholinergic function.
To reverse the actions of a depolarizing neuromuscular blockade that can cross through the blood brain barrier, which drug would you use?
Donepezil
Which other clinical implication does Donepezil have?
It is used to treat Alzheimers disease as it’s a drug that targets the Central Nervous System.
What are the PERIPHERAL side effects of using neostigmine and pyridostigmine?
SLUDGE BBB/ DUMBELLS
For a longer reversal of depolarizing neuromuscular blockades, would you use neostigmine or pyridostigmine?
Pyridostigmine.
Does preventing neuromuscular junction transmission prevent pain?
No
To aid with pain prevention, add anesthetics and analgesics to help prevent anaesthesia awareness as well.
What is the difference between depolarized and non-depolarized neuromuscular blockades?
Non- depolarizing:
Paralyses muscles but does NOT depolarize motor endplate.
Depolarizing
Paralyses muscles by depolarising motor endplate
