Eye Flashcards
(17 cards)
What effect do antimuscarinic drugs have on the eye?
They dilate the pupil (mydriasis) and paralyse the ciliary muscle (cycloplegia).
Which antimuscarinic is a short-acting, relatively weak mydriatic used to facilitate fundus examination?
Tropicamide, with action lasting up to 6 hours.
Name two longer-acting antimuscarinic mydriatics.
Cyclopentolate hydrochloride (recovery up to 24 hours)
Atropine sulfate (action up to 7 days)
What is phenylephrine hydrochloride and how long does its effect last?
A sympathomimetic used for mydriasis in diagnostics or therapy; onset in 60–90 minutes, lasting 5–7 hours.
For what condition are mydriatics and cycloplegics commonly used as adjunct therapy?
Anterior uveitis, usually alongside corticosteroids.
What is the purpose of atropine sulfate or cyclopentolate hydrochloride in anterior uveitis treatment?
To prevent posterior synechiae (adhesions where the iris sticks to the lens behind it) and relieve ciliary spasm. When the pupil is dilated and the ciliary muscle is relaxed, the iris is pulled away from the lens, preventing those sticky adhesions from forming.
What are the two main parts of the eye relevant for drug administration?
Anterior segment and posterior segment.
Which route is most commonly used to treat anterior segment eye diseases?
Topical administration (eye drops and ointments).
When are intravitreal or periocular injections used in eye treatment?
For higher drug concentrations or diseases affecting the posterior segment of the eye.
How should eye drops be applied?
Into the lower eyelid pocket, followed by blinking to spread the medication.
How long should you wait between administering two different eye drops?
At least 5 minutes.
Why is punctal occlusion (pressing the tear duct) advised after eye drop administration?
To reduce systemic absorption of the drug through the nasal mucosa.
Why should ointments be applied after eye drops?
Because ointments can block absorption if applied first and cause blurred vision.
What type of solution is used for eye irrigation?
Sterile sodium chloride 0.9% or clean water in emergencies.
How long can multi-use eye drop containers be safely used after opening?
Usually up to 4 weeks unless otherwise stated.
Should contact lenses be worn when applying eye ointments?
No, ointments should not be used with contact lenses.
Name a few systemic drugs that can affect contact lens wear or eye moisture.
Oral contraceptives, antihistamines, sedative hypnotics, tricyclic antidepressants.
