AOC Pharmacology Fundamentals 3 — Questions and Answers
Question 1: Which cycloplegic agent has the longest duration of action and is used primarily for therapeutic cycloplegia in amblyopia treatment?
- Tropicamide
- Cyclopentolate
- Atropine (Correct answer)
- Phenylephrine
Correct answer: Atropine
Atropine has the longest duration (up to 2 weeks) among cycloplegics and is used in penalization therapy for amblyopia by blurring the fellow eye.
Question 2: Fluorescein sodium, used in clinical practice, primarily serves which diagnostic purpose?
- Measuring corneal thickness
- Detecting corneal epithelial defects under cobalt-blue light (Correct answer)
- Assessing retinal vasculature without imaging
- Measuring intraocular pressure
Correct answer: Detecting corneal epithelial defects under cobalt-blue light
Fluorescein stains areas of disrupted corneal epithelium and fluoresces bright green under cobalt-blue light, revealing abrasions, ulcers, and punctate defects.
Question 3: A patient on oral acetazolamide for IOP control reports tingling in the fingers and toes. What is the most likely cause?
- Peripheral neuropathy from drug toxicity
- Hypokalemia from metabolic acidosis
- Paresthesias due to systemic carbonic anhydrase inhibition (Correct answer)
- Allergic reaction
Correct answer: Paresthesias due to systemic carbonic anhydrase inhibition
Systemic carbonic anhydrase inhibition by acetazolamide causes metabolic acidosis and electrolyte shifts, producing the classic side effect of peripheral paresthesias.
Question 4: Which preservative found in many topical ophthalmic medications is associated with corneal toxicity with prolonged use?
- Sodium chloride
- Benzalkonium chloride (BAK) (Correct answer)
- Polyethylene glycol
- Hydroxypropyl methylcellulose
Correct answer: Benzalkonium chloride (BAK)
Benzalkonium chloride (BAK) is a detergent preservative that disrupts the lipid layer of the tear film and can cause corneal epithelial toxicity with chronic exposure.
Question 5: Rose bengal dye is used in ophthalmic practice to stain which specific tissue type?
- Healthy corneal epithelium
- Dead or devitalized epithelial cells and mucus (Correct answer)
- Corneal stroma
- Conjunctival vessels
Correct answer: Dead or devitalized epithelial cells and mucus
Rose bengal stains dead and devitalized epithelial cells and mucus strands, making it useful for evaluating dry eye disease and herpetic dendrites.
Question 6: What is the preferred route of administration for achieving high intravitreal drug concentrations for posterior segment disease treatment?
- Topical drops
- Oral systemic route
- Intravitreal injection (Correct answer)
- Sub-Tenon injection
Correct answer: Intravitreal injection
Intravitreal injection delivers drug directly into the vitreous cavity, achieving high local concentrations at the retina while minimizing systemic exposure.
Question 7: Sodium hyaluronate ophthalmic solutions are classified as which type of therapeutic agent?
- Antibiotic
- Lubricant and viscosurgical device (Correct answer)
- Cycloplegic
- Antifungal
Correct answer: Lubricant and viscosurgical device
Sodium hyaluronate is a viscoelastic substance used as a lubricant in artificial tears and as an ophthalmic viscosurgical device (OVD) during intraocular surgery.
AOC Pharmacology Fundamentals 3
Which cycloplegic agent has the longest duration of action and is used primarily for therapeutic cycloplegia in amblyopia treatment?