CPOA Ocular Pharmacology 4 — Questions and Answers
Question 1: Which ophthalmic agent is contraindicated in patients with a known sulfa drug allergy?
- Timolol
- Dorzolamide (Correct answer)
- Latanoprost
- Brimonidine
Correct answer: Dorzolamide
Dorzolamide is a carbonic anhydrase inhibitor with a sulfonamide chemical structure, making it contraindicated in patients with sulfa allergies.
Question 2: A patient using brimonidine (Alphagan) should be monitored for which systemic side effect, especially in infants and young children?
- Hypertension
- CNS depression and apnea (Correct answer)
- Hypoglycemia
- Tachycardia
Correct answer: CNS depression and apnea
Brimonidine, an alpha-2 agonist, can cross the blood-brain barrier in young children, causing CNS depression, somnolence, and potentially apnea.
Question 3: Which mydriatic agent also produces cycloplegia (loss of accommodation)?
- Phenylephrine 2.5%
- Hydroxyamphetamine
- Cyclopentolate 1% (Correct answer)
- Epinephrine
Correct answer: Cyclopentolate 1%
Cyclopentolate is an anticholinergic that blocks muscarinic receptors in both the iris sphincter (causing mydriasis) and the ciliary muscle (causing cycloplegia).
Question 4: What is the duration of action of tropicamide 1% for mydriasis?
- 15-30 minutes
- 4-6 hours (Correct answer)
- 24 hours
- 2-3 days
Correct answer: 4-6 hours
Tropicamide 1% produces mydriasis lasting approximately 4-6 hours, making it one of the shorter-acting anticholinergic mydriatics.
Question 5: Fluorescein sodium strips should be moistened with which solution before use?
- Tap water
- Hydrogen peroxide
- Sterile saline or sterile water (Correct answer)
- Proparacaine solution
Correct answer: Sterile saline or sterile water
Fluorescein strips should be moistened with sterile saline or sterile water to prevent contamination and ensure patient safety.
Question 6: Which glaucoma medication works by increasing uveoscleral (alternative) outflow of aqueous humor?
- Timolol
- Acetazolamide
- Latanoprost (Correct answer)
- Pilocarpine
Correct answer: Latanoprost
Prostaglandin analogs like latanoprost remodel the ciliary muscle extracellular matrix, increasing uveoscleral outflow of aqueous humor.
Question 7: An antibiotic eye drop prescribed for bacterial conjunctivitis belongs to which drug category when it ends in '-floxacin'?
- Aminoglycoside
- Fluoroquinolone (Correct answer)
- Macrolide
- Tetracycline
Correct answer: Fluoroquinolone
The '-floxacin' suffix indicates a fluoroquinolone antibiotic (e.g., ciprofloxacin, moxifloxacin), which work by inhibiting bacterial DNA gyrase and topoisomerase IV.
CPOA Ocular Pharmacology 4
Which ophthalmic agent is contraindicated in patients with a known sulfa drug allergy?