From Jen: Autonomic/Cholinergic

Question 1

carbachol

Answer 1

Muscarinic agonist

MOA: binds and activates AChR
(parasympathomimetic)

Tx: glaucoma, pupillary contraction, release intraocular pressure

Contraindication: asthma, coronary insufficiency, ulcers, incontinence

Question 2

scopalamine

Answer 2

Muscarinic antagonist

MOA: competitive antagonist at AChR (M1 in particular)

Tx: CNS- motion sickness, post-op N/V

Question 3

methscopalamine
pirenzepine
propantheline

Answer 3

Muscarinic antagonist

Tx: GI- peptic ulcer

Question 4

atropine

Answer 4

Muscarinic antagonist

Tx: SLUDGE

• salivation
• lacrimation
• urination
• diaphoresis
• GI motility
• emesis

Eye- produce mydriasis, cycloplegia

Question 5

pyridostigmine

Answer 5

AChE inhibitor
-increase endogenous ACh
(lasts 6-8hrs)

DOES NOT CROSS BBB
(quaternary amine)

Tx: Myasthethia gravis
***slower onset and longer duration of action than neostigmine

Question 6

physostigmine

Answer 6

AChE inhibitor
-increase endogenous ACh

CROSS BBB
(tertiary amine)

Tx: Glaucoma, Atropine overdose

Question 7

methacholine

Answer 7

Muscarinic agonist
-stimulates musc receptor when inhaled

Use: challenge for asthma

Question 8

oxybutynin

Answer 8

Muscarinic antagonist

GU- reduce urgency in mild cystitis, reduce bladder spasm

Question 9

glycopyrrolate

Answer 9

Muscarinic antagonist

Pre-op- reduce respiratory secretions, w/neostigmine- reduce muscarinic effects (bradycardia)

GI- decrease acid secretion/ulcers

Question 10

bethanechol

Answer 10

Selective muscarinic agonist
(no nicotinic receptor effect)

Resistant to AChE (long duration of action)

Post-op- neurogenic ileus, urinary retention
Activates bowel and bladder smooth muscle

Question 11

benztropine

Answer 11

Muscarinic antagonist
Dopaminergic agonist

MOA: selective M1 receptor antagonist, increase DA by blocking reuptake

CNS- 2nd line for Parkinson’s
(Park your Benz)
-improve tremor
-no change in rigidity, bradykinesia

Improve extrapyramidal sx w/ antipsychotics

Question 12

AChE inhibitor poisoning

Answer 12

Causes SLUDGE

• salivation
• lacrimation
• urination
• diaphoresis
• GI motility
• emesis

Tx: atropine (muscarinic antagonist)

Question 13

Actions of atropine

Answer 13

Muscarinic antagonist

Eye: mydriasis (dilation)
Airway: decrease secretions
GI: decrease stomach acid secretion, decrease motility
Bladder: decrease spasm/urgency

Question 14

neostigmine

Answer 14

Reversible AChE inhibitor
-increase endogenous ACh
Lasts 2-4 hrs

DOES NOT CROSS BBB
(quaternary amine)

Myasthenia gravis
***faster onset and shorter duration than pyridostigmine

Post-op: neurogenic ileus, urinary retention, reversal of NMJ blockade

Ogilvie syndrome- colonic pseudoobstruction

Question 15

Pilocarpine

Answer 15

Muscarinic agonist
Resistant to AChE (long duration of action)

Uses: stimulate sweat, tears, saliva
contract ciliary muscle of eye

Question 16

Echothiophate

Answer 16

AChE inhibitor
-increase endogenous ACh

Tx: glaucoma

Question 17

Ipratropium

Answer 17

Muscarinic antagonist

DOES NOT CROSS BBB
(quaternary amine)

Respiratory- Asthma, COPD

Question 18

Hexamethonium

Answer 18

Nicotinic antagonist
ganglionic blocker
-preganglionic

Ganglionic blocker: prevent vagal reflex (reflex bradycardia from NE)

Toxicity: Orthostatic hypotension, blurred vision, constipation, sexual dysfunction

Question 19

Edrophonium

Answer 19

AChE inhibitor
-increase endogenous ACh

Dx: myasthenia gravis
**Extremely short acting

Question 20

Atropine Toxicity

Answer 20

HOT- increase temp
BLIND- blurry vision, pupil dilation
DRY- mouth and skin
MAD- confusion, hallucinations
RED- vasodilation

• **elderly: acute angle glaucoma
• **men w/ BPH: urinary retention
• **infants: hyperthermia

Question 21

Echothiophate

Answer 21

AChE inhibitor
-increase endogenous ACh

Tx: glaucoma