Ocular Pharmacology Flashcards
Name the 3 direct muscarinic agonists and their mechanism of action
Acetylcholine, Pilocarpine, Carbachol
cause pupillary constriction and increase aqueous outflow
What are the direct muscarinic agonists used to tx and what are their side effects
Tx: Cataract surgery, tx of glaucoma
Side Effects: SLUDGE + bronchospasm, sweating
Name the indirect muscarinic agonist, it’s mechanism of action and what it’s used to tx
1) Echothiophate iodide
2) MOA: irreversibly binds cholinesterase
3) Cycloplegia for eye exams, improves discomfort during active eye inflammation (uveitis)
Name the 5 antimuscarinic ocular drugs
Atropine, Scopolamine, Homatropine, Cyclopentolate, Tropicamide
What is the mechanism of action for the antimuscarinic drugs?
Pupillary dilation, paralysis of ciliary body
What do the antimuscarinic drugs tx?
Cycloplegia (paralysis of ciliary muscle) for eye exams, improve discomfort during active eye inflammation (uveitis)
What are the side effects of the antimuscarinic drugs?
Ataxia, nystagmus, restlessness, mental confusion, hallucination, violent and aggressive behavior, insomnia, photophobia, urinary retention
Which of the antimuscarinics has the longest recovery time and which has the shortest (and thus is most preferred in typical eye exams)?
1) longest = Atropine (7-10 day recovery)
2) shortest = Tropicamide (several hrs recovery)
What type of drug is Edrophonium? What’s it’s mechanism and what does it diagnose?
It’s a Nm agonist that destroys acetylcholinesterase. It’s used to diagnose myasthenia gravis
How does epinephrine act in the eye? What does it treat?
Epinephrine is a direct adrenergic agonist; it dilates the episcleral vessels to increase aqueous outflow; thus it treats glaucoma
What are the side effects of epinephrine? What is the name of an epinephrine prodrug?
Side effects include extrasystoles, palpitation, HTN, myocardial infarction, trembling, paleness, sweating.
Prodrug of epi is Dipivefrin HCl
Name two indirect adrenergic agonists and how they act?
1) Hydroxyamphetamine – releases NE
2) Cocaine – prevents reuptake of NE
How does Hydroxyamphetamine help diagnose Horner’s syndrome?
It separates 1st and 2nd from 3rd order neuron dysfunction. A positive dilation upon administration means 1st or 2nd order neuron problem (an ominous sign)
What type of drug is Apraclonidine and what is it used to treat?
It’s a direct alpha agonist (and an amino derivative of clonidine).
It does not cross BBB so has minimal effect on systemic blood pressure
What type of drug is Phenylephrine and what does it tx?
It’s a direct alpha 1 agonist used to dilate the pupil.
What type of drug is Clonidine and what is its MOA?
It’s a direct alpha 2 agonist.
It lowers IOP through CNS effects
What type of drug is Brimonidine tartrate and what is it’s MOA?
It’s a direct alpha 2 agonist. It suppresses aqueous humor production through action of cAMP in non-pigmented ciliary epithelium
When is Brimonidine tartrate contraindicated?
Contraindicated with follicular conjunctivitis; and when used with MAO inhibitor it can cause fatigue/drowsiness