Cholinoceptor Blockers Flashcards
competitively blocks all muscarinic receptors
drug of choice for organophosphate poisoning
mydriatic, cycloplegic, bradycardia, hypersalivation
Atropine
Homatropine, Cyclopentolate, Tropicamide
competitively blocks all muscarinic receptors
restores neurotransmitter balance in basal ganglia
used for Parkinson’s Disease
(reduces tremors more than bradykinesia/rigidity)
Benztropine
Biperiden, Trihexyphenidyl
blocks muscarinic receptors in bronchial smooth muscle
prevents vagal-stimulated bronchoconstriction
for asthma, COPD (especially in those with COPD and heart disease)
Ipratropium
Tiotropium
competitively blocks all muscarinic receptors
antagonizes histamine and serotonin
used for motion sickness, decrease acid secretion in GIT
Scopolamine
competitively blocks M3 receptors
used for IBS, minor diarrhea, decrease acid secretion in GIT
relatively short half life (6 hours)
Dicylomine
Hyoscyamine, Glycopyrolate
slightly blocks M3 receptors
reduces detrusor muscle tone
used for urge incontinence, post-operative spasms
Oxybutynin
Darifenacin, Solifenacin, Tolteradine, Trospium
Atropine Toxicity
HOT AS HARE: atropine fever (hyperthermia)
RED AS BEET: atropine flush (cutaneous vasodilation)
DRY AS BONE: decreased secretions
BLIND AS BAT: blurred vision
MAD AS A HATTER: CNS toxicity
tachycardia, arrhythmias (interventricular conduction block)
constipation
Contraindications to muscarinic blockers
- infants
- acute angle closure glaucoma
- benign prostatic hyperplasia
competitively blocks Nn nicotinic Ach receptors
previously used for HTN (obsolete), hypertensive emergencies
SIDE EFFECT: postural hypotension, dry mouth, blurred vision, constipation, sexual dysfunction
Hexamethonium
Trimethaphan, Mecamylamine
produces complete skeletal muscle relaxation in surgery
Neuromuscular blockers
Non-Depolarizing Neuromuscular Blockers
Tubocurarine
Pancuronium
Atracurium
Vecuronium
Depolarizing Neuromuscular Blockers
Succinylcholine
