Autonomic Drugs Flashcards
Mechanism of hemicholinium.
Blocks Na/Choline contransport by pre-synaptic axon
Mechanism of Vesamicol.
Blocks packaging of ACh in the pre-synaptic cholinergic neuron.
Mechanism of Botulinum.
Cleaves SNARE proteins that prevent docking of ACh vessicles in pre-synaptic neuron.
Mechanism of Metyrosine
Inhibits tyrosine hydroxylase (no L-DOPA formation) in adrenergic pre-synaptic neuron.
Mechanism of Reserpine
Blocks packaging of dopamine into neurosecretory vessicles. (in adrenergic neurons)
What drugs can increase NE release from pre-synaptic neuron?
Amphetamine, ephedrine, tyramine
What drugs can inhibit re-uptake of NE by pre-synaptic neuron?
TCA, cocaine, amphetamine
What are 2 enzymes that metabolize norepi?
COMT
MAO
What is metabolite of epinephrine?
metanephrine
Metabolite of NE
VMA
Metabolite of Dopmaine
Homovanillic acid
What are the 4 direct cholinergic agonists?
Bethanochol (ileus and urinary retention)
Pilocarpine (contracts ciliary muscle and pupillary sphincter) –> Glaucoma
Methacholine (challenge test for asthma)
Carbachol (miosis and relieves IOP in glaucoma)
What are the 6 acetylcholinesterase inhibitors?
Donepezil, galantamine, rivastigmine (PD)
Edrophonium (dx MG)
Neostigmine (MG, ileus, urinary retention)
Physostigmine (glaucoma)
Pyridostigmine (MG)
Echothiophage (glaucoma)
What 2 drugs are used in reversing organophosphate poisoning?
Atropine / Pralidoxime
What are the muscarinic antagonists used in the eye?
Atropine
Homatropine
Tropicamide (mydriasis and cycloplegia)
What are the muscarinic antagonists used in the CNS
Benztropine (Parkinsons) –> combats side effects of anti-psychotics
Which muscarinic antagonists are used in the respiratory system?
Ipratropium
Tiotropium (Bronchodilation in COPD / asthma)
LAMA
What are the muscarinic antagnoists used in urge urinary incontinence?
"On The Darn Toilet" Oxybutynin Tolterodine Darifenecin Trospium Solifenacin
What anti-muscarinic can be used in motion sickness?
Scopolamine
Non-depolarizing NMJ Blockers and their mode of action
Tubocurarine, atracurium, mivaruium, pancuronium, vecuronium, rocuronium
Compete with ACh for receptor at NMJ
Reverse with neostigmine + Atropine (prevent cholinergic side effects)
Depolarizing NMJ blocker and its mode of action
Succinylcholine
Strong ACh receptor agonist. Depolarizes and inhibits repolarization.
Phase 1 = prolonged depolarization
Phase 2 = repolarized but blocked –> ACh receptors available but desensitized
Cholinesterase inhibitors potentiate during phase 1 and block action during phase 2.
