Autonomic Drugs

Question 1

Mechanism of hemicholinium.

Answer 1

Blocks Na/Choline contransport by pre-synaptic axon

Question 2

Mechanism of Vesamicol.

Answer 2

Blocks packaging of ACh in the pre-synaptic cholinergic neuron.

Question 3

Mechanism of Botulinum.

Answer 3

Cleaves SNARE proteins that prevent docking of ACh vessicles in pre-synaptic neuron.

Question 4

Mechanism of Metyrosine

Answer 4

Inhibits tyrosine hydroxylase (no L-DOPA formation) in adrenergic pre-synaptic neuron.

Question 5

Mechanism of Reserpine

Answer 5

Blocks packaging of dopamine into neurosecretory vessicles. (in adrenergic neurons)

Question 6

What drugs can increase NE release from pre-synaptic neuron?

Answer 6

Amphetamine, ephedrine, tyramine

Question 7

What drugs can inhibit re-uptake of NE by pre-synaptic neuron?

Answer 7

TCA, cocaine, amphetamine

Question 8

What are 2 enzymes that metabolize norepi?

Answer 8

COMT

MAO

Question 9

What is metabolite of epinephrine?

Answer 9

metanephrine

Question 10

Metabolite of NE

Answer 10

VMA

Question 11

Metabolite of Dopmaine

Answer 11

Homovanillic acid

Question 12

What are the 4 direct cholinergic agonists?

Answer 12

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)

Question 13

What are the 6 acetylcholinesterase inhibitors?

Answer 13

Donepezil, galantamine, rivastigmine (PD)
Edrophonium (dx MG)
Neostigmine (MG, ileus, urinary retention)
Physostigmine (glaucoma)
Pyridostigmine (MG)
Echothiophage (glaucoma)

Question 14

What 2 drugs are used in reversing organophosphate poisoning?

Answer 14

Atropine / Pralidoxime

Question 15

What are the muscarinic antagonists used in the eye?

Answer 15

Atropine
Homatropine
Tropicamide (mydriasis and cycloplegia)

Question 16

What are the muscarinic antagonists used in the CNS

Answer 16

Benztropine (Parkinsons) –> combats side effects of anti-psychotics

Question 17

Which muscarinic antagonists are used in the respiratory system?

Answer 17

Ipratropium
Tiotropium (Bronchodilation in COPD / asthma)
LAMA

Question 18

What are the muscarinic antagnoists used in urge urinary incontinence?

Answer 18

"On The Darn Toilet"
Oxybutynin
Tolterodine
Darifenecin
Trospium 
Solifenacin

Question 19

What anti-muscarinic can be used in motion sickness?

Answer 19

Scopolamine

Question 20

Non-depolarizing NMJ Blockers and their mode of action

Answer 20

Tubocurarine, atracurium, mivaruium, pancuronium, vecuronium, rocuronium

Compete with ACh for receptor at NMJ

Reverse with neostigmine + Atropine (prevent cholinergic side effects)

Question 21

Depolarizing NMJ blocker and its mode of action

Answer 21

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.