FA Cholinomimetics Flashcards
Bethanechol
Direct muscarinic receptor agonist; activates bowel and bladder smooth muscle; resistant to AChE;
Carbachol
Carbon copy of ACh;
CU bethanechol
postoperative ileus, neurogenic ileus, urinary retention
CU carbechol
glaucoma, pupillary constriction, relief of IOP
CU pilocarpine
potent stimulator of sweat, tears and saliva; open and closed angle glaucoma
CU methacholine
challenge test for diagnosis of asthma
Pilocarpine
Contracts ciliary muscle of eye (open-angle glaucoma), contracts pupillary sphincter (closed-angle glaucoma);
“you cry, drool, and sweat on your pillow”
Methacholine
Stimulates muscarinic receptors in airway when inhaled
CU neostigmine
postoperative and neurogenic ileus and urinary retention, Myasthenia gravis, reversal of NMJ blockage (postoperative)
Neostigmine
anticholinesterase (neo CNS = no CNS)
CU pyridostigmine
Myasthenia gravis (long acting); does not penetrate CNS
Pyridostigmine
anticholinesterase –> inc ACh and strength; does not penetrate CNS
CU Physostigmine
anticholinergic toxicity (ie jimson weed, atropine overdose); crosses BBB –> CNS
physostigmine
anti cholinesterase that crosses BBB
Name three AChE inhibitors that work for Alzheimer’s
rivastigmine, galantamine, donepezil
Historically, dx of myasthenia gravis (extremely short acting). MG now diagnosed by anti-ChR aAB test.
Edrophonium
General toxicities of all indirect and direct cholinomimetics
exacerbation of COPD, asthma, PUD
4 direct cholinomimetics
bethanechol, carbachol, pilocarpine, methacholine
7 indirect cholinomimetics
Neo-, pyrido-, physio- stigmine
rivastigmine, galantamine, donepezil
Cholinesterase inhibitor poisoning (often due to organophosphates (parathion) that irreversibly inhibit AChE –> too much ACh)
DUMBBELS Diarrhea Urination Miosis Bronchospasm Bradycardia Excitation of skeletal muscle and CNS Lacrimation, Sweating Salivation
Antidote to organophosphate poisoning
atropine (competitive inhibitor) + pralidoximine (regenerates AChE if given early)
Atropine, homatropine, tropic amide effect on eye
mydriasis (pupil dilation) and cycloplegia (paralysis of the ciliary muscle of the eye –> loss of accommodation)
benztropine
muscarinic antagonist for Parkinson’s disease
scopolamine
muscarinic antagonist for motion sickness
ipratropium, tiotropium
muscarinic antagonist for COPD, asthma
oxybutynin,
darifenacin,
solifenacin
reduce urgency in mild cystitis and reduce bladder spasms
Other agents: tolterodine, fesoterodine, trospium
Glycopyrrolate
Affects GI and respiratory systems.
Parenteral: postoperative use to reduce airway secretions
Oral: drooling, peptic ulcer
atropine effect on airway
decreases secretions
atropine effect on stomach
decreases acid secretion
atropine effect on gut motility
decreases
atropine effect on bladder
decreases urgency in cystitis
atropine effects
inc pupil dilation, cycloplegia
dec AW secretions, stomach acid, gut motility, urgency in cystitis
Atropine toxicity
Hot as a hare (inc temp due to dec sweating)
Dry as a bone (dry mouth + skin)
Red as a beet (flushed skin)
Blind as a bat (cycloplegia, mydriasis)
mad as a hatter (disorientation… and constipation)
special populations to worry about with atropine toxicity
acute angle-closure glaucoma in elderly (mydriasis),
urinary retention in men w/ BPH,
hyperthermia in infants
