Direct acting cholinolytics Flashcards
What type of drug is atropine?
Anticholinergic muscarinic antagonist
cholinolytic = anticholinergic = cholinergic receptor antagonist
Blocks muscarinic receptors, reducing parasympathetic tone.
What is the mechanism of action of atropine?
Mechanism of action: competitive muscarinic cholinergic receptor antagonists
Binds to the muscarinic cholinergic receptor in the target tissue and blocks the action → decreased PNS response
cholinolytic = anticholinergic = cholinergic receptor antagonist
List three indications for atropine.
- Induces mydriasis (dilation)
- Reduces secretions
- Treatment of ventricular bradycardia
- Treatment of severe diarrhea and urinary bladder incontinence
Not commonly used for diarrhea or urinary incontinence due to systemic side effects.
What is scopolamine classified as?
Muscarinic antagonist
cholinolytic = anticholinergic = cholinergic receptor antagonist
Inhibits muscarinic receptors to decrease secretions and vestibular stimulation.
What is the MoA of scopolamine?
Inhibits cholinergic activation of emesis center;
inhibits muscarinic receptors to decrease secretions and vestibular stimulation
What are the uses of scopolamine?
- Treatment of motion sickness
- PONV prevention
What is solifenacin (Vesicare)?
Selective M3 cholinergic receptor antagonist
cholinolytic = anticholinergic = cholinergic receptor antagonist
Reduces PNS control over the contractile state of the detrusor muscle that lines the urinary bladder.
What is the MoA of solifenacin (Vesicare)?
is a selective M3 muscarinic cholinergic receptor antagonist that reduces PNS control over the contractile state of the detrusor muscle that lines the urinary bladder
What condition does solifenacin primarily treat?
Overactive bladder (OAB; detrusor instability or overactivity)
Affects up to 33% of the US population.
What is tolterodine classified as?
Muscarinic antagonist
cholinolytic = anticholinergic = cholinergic receptor antagonist
Blocks muscarinic receptors in the bladder, decreasing urgency and frequency.
What condition is tolterodine used to treat?
Overactive bladder
It decreases urgency and frequency of urination.
What are general SE of cholinolytics?
SE are opposite of PNS effects:
mydriasis, photophobia, anhidrosis bc sweat glands blocked, blurred vision, increased intraocular pressure, xerostomia, incr HR, tachycardia, bronchodilation, AMS/hallucinations, urinary retention, constipation
What’s the mneumonic for anticholinergic toxicity?
blind as a bat
dry as a bone
red as a beet
mad as a hatter
full as a flask
hot as a hare
Anticholinergic toxicity:
Can’t see, can’t —, can’t spit, can’t —.
Can’t see, can’t pee, can’t spit, can’t shit.
Anticholinergic toxicity:
Can’t —, can’t pee, can’t —, can’t shit.
Can’t see, can’t pee, can’t spit, can’t shit.
What’s the issue w/taking solifenacin (vesicare) or tolteridine with a CYP inducer or inhibitor?
Both metab by CYP3A4.
* If pt taking an inhibitor, metab of solifenacin slows down, increasing levels and possibly leading to anticholinergic toxicity.
* If pt taking inducer, metab of solifenacin speed up, decr drug levels, making it ineffective for txt for overactive bladder.
Why are antimuscaric drugs contraindicated w/glaucoma?
if the muscarinic receptor is blocked, ciliary muscle stays relaxed and schlem’s canal never cleared and intraocular pressure can get worse
Drug inter.s w/drugs not considered anticholin. can still –> blockade
What are some examples and how are they treated?
non anticholin that produce blockade:
* antihistamines
* phenothiazine antipsychotics
* TCA
Treat w/neostigmine
