Indirect Acting Cholinomimetics Flashcards
What is the mechanism of action of acetylcholinesterase inhibitors?
Reversible inhibition of acetylcholinesterase, causing ACh to accumulate in the synapse and enhance cholinergic function
They actually bind to AChase and take longer to be hydrolyzed than Ach so they just let more of the natural ligand be around to activate the receptor
What type of drug is neostigmine?
ACHase inhibitor
What is the primary clinical use of neostigmine?
Treats GI and urinary bladder paralysis, glaucoma, myasthenia gravis, and anticholinergic effects caused by some drugs like phenothiazides
Neostigmine does not pass the blood-brain barrier (BBB).
What type of drug is donepezil?
ACHase inhibitor
What condition is donepezil primarily used to treat?
Alzheimer’s disease associated with loss of cholinergic control of short-term memory
Donepezil passes the BBB and can cause dizziness and headaches but is not curative.
What is sarin classified as?
An irreversible acetylcholinesterase inhibitor and nerve gas
Sarin covalently binds and inactivates AChE, leading to excessive acetylcholine and cholinergic crisis.
What is the treatment required for life-threatening cholinergic crisis caused by sarin or parathione?
pralidoxime (PAM) - breaks chemical bonds between drugs and ACHase
Sarin is not used therapeutically and is a chemical warfare nerve agent.
What type of substance is parathione?
An irreversible acetylcholinesterase inhibitor and insecticide
Exposure can lead to severe cholinergic toxicity, and an antidote with pralidoxime is required.
True or False: Neostigmine can pass the blood-brain barrier.
False
Neostigmine does not have central effects due to its inability to pass the BBB.
Fill in the blank: Donepezil is used to treat _______.
symptoms of Alzheimer’s disease
What are the potential effects of donepezil due to its ability to pass the BBB?
Can cause dizziness and headaches
Donepezil produces central effects but is not curative.
What is the antidote for parathione poisoning?
Pralidoxime
breaks chemical bonds between drugs and ACHase
What is the acronym mnemonic for a cholinergic crisis?
DUMBELS
Diaphoresis/diarrhea/defecation
Urination
Miosis/muscle weakness
Bradycardia/bronchospasm/Bronchorrhea
Emesis
Lacrimation
Salivation
What is important to know about side effects for indirect acting cholinomimetics?
SE: can cause generalized exaggerated PNS side effects
