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Pilocarpine
- -direct-acting cholinergic receptor agonist
- -activates parasympathetic system -> constricts iris and ciliary muscle, used for glaucoma
- -resistant to cholinesterases
- -Adverse effects: CNS disturbances, profuse sweating and salivation
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Physostigmine
- reversible inhibitor of cholinesterases -> activates PNS
- -bind at carbamylate active site and more resistant to hydration so longer duration (30-120mins)
- -used to treat glaucoma, myasthenia gravis, Alzheimers
- -adverse effects: enter CNS -> convulsions
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Neostigmine
- similar to physostigmine, a carbamate ester, BUT water soluble so does NOT enter CNS
- -reversibly inhibits cholinesterase -> mitotic agent to treat glaucoma short term (30-120 mins)
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Edrophonium
- -reversible antagonist of cholinesterase
- -class: quaternary alcohol
- -short duration (10-20 mins) mitotic for glaucoma
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Isofluorophate
- -irreversible inhibitor of cholinesterase (covalently phosphorylate cholinesterase) -> activates PNS
- -used as intense, prolonged mitotic agents for treatment of glaucoma
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Epinephrine
- -Non-selective alpha-adrenoceptor agonist -> stimulates SNS
- -dilation of iris (small effect)
- -increases AH outflow (major effect) and decreses AH secretion -> Tx for glaucoma
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Timolol
- -Beta adrenoceptor blocker
- -decreases AH production
- -Tx for glaucoma
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Atropine
- -Antimuscarinic (AchR antagmonist) -> Mydriasis and cycloplegia -> Measure refractive errors of young children without
- accommodation capacity, retinal examinations
- -long acting (7-10 days)
- Tx: physostigmine
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Clinical uses of antimuscarinics
- -Inhibits PNS (so SNS is in effect)
- -mydriasis, decrease synechia in anterior uveitis
- -antispasmodics (GI activity decreases)
- -anesthetic
- -opens bronchioles
- -urinary incontinence
- -increase HR
- -antidote for cholinergic agents
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