Eye drugs 5.15 Flashcards
What is the action of a sympathomimetic drug - which receptors do they act on?
Mimic / induce sympathetic system - act on alpha receptors - cause mydriasis: dilate pupil
Phenylephrine is what type of drug
sympathomimetic - stim sympath system
How long might phenylephrine effects last
5-7 hrs
What effect to antimuscarinics have on nerv.sys
Block parasympathetic system - cause mydriasis
Egs of antimuscarinics (3)
Atropine, cyclopentolate, tropicamide
Give a use for each of the following antimuscarinics: Atropine, cyclopentolate,
Atropine - stimulating mydriasis rapidly (in 15mins)
Cyclopentolate - Cycloplegia (paralysis of cilliary muscles) eg in uveitis (v painful)
SE of sympathomimetics (4)
Photophobia
blurred vision
Less effective in DM, dark iris or elderly
SE of antimuscarinics
Photophobia
blurred vision
Raised IOP - avoid with glaucoma
Stinging on application
How do parasympathomimetics work - what used for
Act on muscarinic receptors - mimic Ach action
Open up drainage channels in trabecular meshwork
Reverse mydriasis within 30mins
What condition are parasympathomimetics use for
Glaucoma (open up trabec drainage channels)
Pilocarpine is a parasympathomimetic - SE(4)
Headache
Stinging on instillation
Myopia
Risk of retinal detachment
What is flourescein used for
Orange dye - for examining eye - cornea / conjunctiva damage
Proxymetacaine and lidocaine are used for what
anaesthatizing eye
What treatment would be used for superficial eye infections
Chloramphenicol eye drops 0.5% (OTC med)
Digoxin causes disturbance of what in the vision
Colour vision
