Cholinergic Antagonists

Cholinergic antagonists

agents that bind to m or N AChRs and prevent effects of acetylcholine

Antimuscarinic agents

block mAChRs at postganglionic NMJ (PSNS)

little/no action at skeletal NMJ/autonomic ganglia

opposite of SLUDGE BAM (HRBMD)

Atropine

antimuscarinic agent

DOA: 4-6 hr

mydriasis

heart effects

bradycardia tx

cholinergic agonist antidote

Cyclopentolate

antimuscarinic agent

DOA: 6-24 hr

mydriasis

cycloplegia

Tropicamide

antimuscarinic agent

DOA: 6-7 hr

mydriasis

cycloplegia

Ipratropium

antimuscarinic agent

SAMA

maintenance tx COPD, acute asthma tx

Antimuscarinic agent

LAMA

maintenance tx COPD

“I Got Through Asthma”

glycopyrrolate

tiotropium (asthma)

aclidinium

Antimuscarinic agent

Parkinson’s tx

“The Brain”

Trihexyphenidyl

Benztropine

Antimuscarinic agent

M3 tx overactive bladder

“SOFTT blaDder”

solifenacin

oxybutynin

fesoterodine

tolterodine

trospium

darfenacin

Scopolamine

antimuscarinic agent

patch, prevents motion sickness

post-op n/v tx

Nicotine

ganglionic blocker

dose dependent

complex effects

smoking cessation

Neuromuscular blocking agents (nondepolarizing)

[low]:

blocks ACh at nAChRs

prevents skeletal muscle contraction

reversible by cholinesterase inhibitors

[high]:

cholinesterase inhibitors can’t reverse

cannot cross BBB

Cisatracurium

neuromuscular blocking agents (nondepolarizing)

mechanical ventilation in multisystem organ failure

Mivacurium

neuromuscular blocking agents (nondepolarizing)

eliminated by plasma cholinesterase

Pancurorium

neuromuscular blocking agents (nondepolarizing)

excreted unchanged

Neuromuscular blocking agents (nondepolarizing)

deacetylated in liver

excreted unchanged in bile

rocuronium

vecuronium

Depolarizing

constant receptor stimulation

useful for rapid intubation, ECT

Succinylcholine

depolarizing

rapid onset

short DOA

AE: hyperthermia, apnea d/t paralysis of diaphragm, hyperkalemia

Cholinergic antagonist general effects

“HRBMD”

Hot as a hare-increased temp d/t decreased sweating

Red as a beet-flushing (skin, decreased sweating)

Blind as a bat mydriasis (pupil dilation)

Mad as a hatter-delirium/confusion

Dry as a bone-dry mouth/eyes, decreased secretions