A muscarinic receptor antagonist is an agent that reduces the activity of the muscarinic acetylcholine receptor . Most of them are synthetic, but scopolamine atropine are belladonna alkaloids, and are naturally extracted.
Additional recommended knowledge
Important[1] muscarinic agonists include atropine , hyoscine, ipratropium , tropicamide, cyclopentolate and pirenzepine .
Comparison table
Substance
Trade names
Mechanism[2]
Clinical use[2]
Adverse effects[2]
Atropine (D/L-Hyoscyamine )
non-selective antagonism, CNS stimulation
in anaesthesia
anticholinesterase poisoning
bradycardia
antispasmodic in gastrointestinal hypermotility
urinary retention
xerostomia
blurred vision
Scopolamine (L-Hyoscine)
non-selective antagonism, CNS depression
as atropine
motion sickness
Ipratropium
non-selective antagonism, without any mucociliary excretion inhibition.
Tropicamide
short acting non-selective antagonism, CNS depression
produce mydriasis and cycloplegia in diagnostics
may cause ocular hypertension
Pirenzepine
M1 receptor-selective antagonist
inhibits gastric secretion
in peptic ulcer (not much anymore)
(fewer than non-selective ones)
Diphenhydramine
Benadryl
Dimenhydrinate
Dramamine
dicyclomine
flavoxate
oxybutynin
tiotropium
Spiriva
cyclopentolate
short acting non-selective antagonism, CNS depression
produce mydriasis and cycloplegia in diagnostics
may cause ocular hypertension
atropine methonitrate
non-selective antagonism, blocks transmission in ganglia
trihexyphenidyl
Artane
tolterodine
Detrusitol
solifenacin
Vesicare
darifenacin
Enablex
benztropine
Cogentin
See also
References
^ Rang, H. P. (2003). Pharmacology . Edinburgh: Churchill Livingstone. ISBN 0-443-07145-4 . Page 147
^ a b c Unless else specified in table boxes, then ref is: Rang, H. P. (2003). Pharmacology . Edinburgh: Churchill Livingstone. ISBN 0-443-07145-4 . Page 147
Urologicals (G04 ) Acidifiers Ammonium chloride , Calcium chloride Urinary antispasmodics (primarily antimuscarinics ) Darifenacin , Emepronium , Flavoxate , Meladrazine, Oxybutynin , Propiverine , Solifenacin , Terodiline , Tolterodine , TrospiumFor erectile dysfunction Alprostadil , Apomorphine , Moxisylyte, Papaverine , Phentolamine , Yohimbine , PDE5 inhibitors (Avanafil , Sildenafil , Tadalafil, Udenafil , Vardenafil )Other urologicals Acetohydroxamic acid , Collagen , Dimethyl sulfoxide , Magnesium hydroxide, Pentosan polysulfate, Phenazopyridine, Phenyl salicylate, Succinimide For benign prostatic hypertrophy 5α-reductase inhibitors : Dutasteride , Finasteride
Alpha blockers : Alfuzosin , Doxazosin , Tamsulosin , Terazosin
Herbals: Pygeum africanum , Serenoa repens