CPOA Ocular Pharmacology 5 — Questions and Answers
Question 1: Which topical ophthalmic agent is used to reverse the effects of phenylephrine-induced mydriasis?
- Pilocarpine (Correct answer)
- Atropine
- Tropicamide
- Timolol
Correct answer: Pilocarpine
Pilocarpine, a cholinergic miotic agent, constricts the pupil by stimulating the iris sphincter muscle, reversing sympathomimetic mydriasis.
Question 2: Atropine 1% has a longer duration of cycloplegia than cyclopentolate 1%. Approximately how long does atropine's cycloplegic effect last?
- 4-6 hours
- 12 hours
- 1-2 weeks (Correct answer)
- Up to 2-3 weeks
Correct answer: 1-2 weeks
Atropine's cycloplegic effect can persist for 7-14 days (up to 2 weeks), making it useful in pediatric refraction but inconvenient for routine dilation.
Question 3: Sodium hyaluronate and carboxymethylcellulose are common active ingredients in which type of ocular product?
- Glaucoma drops
- Artificial tears / lubricating eye drops (Correct answer)
- Antibiotic eye drops
- Antifungal eye drops
Correct answer: Artificial tears / lubricating eye drops
Sodium hyaluronate and carboxymethylcellulose are viscosity-enhancing agents that lubricate and moisturize the ocular surface, used in artificial tear preparations.
Question 4: A patient reports a severe allergic reaction to an ophthalmic medication. Which finding would indicate anaphylaxis requiring emergency response?
- Mild itching of the eyelids
- Localized conjunctival redness
- Difficulty breathing and hypotension (Correct answer)
- Slight watering of the eye
Correct answer: Difficulty breathing and hypotension
Anaphylaxis presents with systemic symptoms including respiratory distress and cardiovascular collapse (hypotension), requiring immediate emergency intervention.
Question 5: Which antiviral medication is used topically to treat herpes simplex keratitis?
- Neomycin
- Natamycin
- Trifluridine (Viroptic) (Correct answer)
- Voriconazole
Correct answer: Trifluridine (Viroptic)
Trifluridine (trifluorothymidine) is a topical antiviral that inhibits viral DNA synthesis and is the first-line treatment for HSV epithelial keratitis.
Question 6: When a patient is using multiple eye drops, what is the recommended minimum waiting time between instillation of different drops?
- 30 seconds
- 2-3 minutes (Correct answer)
- 10 minutes
- No wait time needed
Correct answer: 2-3 minutes
A minimum interval of 2-5 minutes between drops is recommended to allow each medication to be absorbed before the next drop washes it out.
Question 7: Natamycin ophthalmic suspension is used to treat which type of ocular infection?
- Bacterial conjunctivitis
- Fungal keratitis (Correct answer)
- Viral keratitis
- Chlamydial conjunctivitis
Correct answer: Fungal keratitis
Natamycin is a polyene antifungal that binds to ergosterol in fungal cell membranes and is the only FDA-approved topical antifungal for fungal keratitis.
CPOA Ocular Pharmacology 5
Which topical ophthalmic agent is used to reverse the effects of phenylephrine-induced mydriasis?