Cholinomimetic Drugs Flashcards
Bethanechol
Direct agonist
Activates bowel and bladder smooth muscle
Resistant to AChE
No nictonic activity
*Used for: post-op ileus, neurogenic ileus, urinary retention
Carbachol
Direct agonist
Carbon copy of ACh
Resistant to AChE
*Constricts pupil and relieves intraocular pressure in open-angle glaucoma
Methacholine
Direct agonist
Stimulates muscarinic receptors in airway when inhaled
*Challenge test for diagnosis of asthma
Pilocarpine
Direct agonist
Contracts ciliary muscle of eye (open-angle glaucoma) and pupillary sphincter (closed-angle glaucoma)
Resistant to AChE
Can cross BBB (tertiary amine)
- Potent stimulator of sweat, tears, and saliva (cry/drool/sweat on pilo)
- Open-angle and closed-angle glaucoma, xerostomia (Sjogren syndrome)
Galantamine
Indirect agonist (anticholinesterase) Increase ACh
*Alzheimer disease
Donepezil
Indirect agonist (anticholinesterase) Increase ACh
*Alzheimer disease
Rivastigmine
Indirect agonist (anticholinesterase) Increase ACh
*Alzheimer disease
Edrophonium
Indirect agonist (anticholinesterase) Increase ACh
*Historically used to diagnose MG-replaced by anti-AChR Ab test
Neostigmine
Indirect agonist (anticholinesterase)
Increase ACh
NO CNS penetration (quaternary amine)
*Post-op and neurogenic ileus and urinary retention, MG, reversal of NMJ blockade post-op
Physostigmine
Indirect agonist (anticholinesterase)
Increase ACh
Physostigmine “phyxes” atropine overdose
Freely cross BBB (tertiary amine)
*Antidote for anticholinergic toxicity
Pyridostigmine
Indirect agonist (anticholinesterase)
Increase ACh
Increase muscle strength
Does NOT penetrate CNS (quaternary amine)
*Long-acting MG treatment
Cholinesterase inhibitor poisoning
Irreversible inhibition of AChE = TOO much ACh
*Diarrhea, Urination, Miosis, Bronchospasm, Bradycardia, Excitation of skeletal muscle and CNS, Lacrimation, Sweating, Salivation
May lead to respiratory failure if untreated
*Antidote = atropine (competitive inhibitor) + pralidoxime (regenerates AChE if given early)
