AOC Pharmacology Fundamentals 2 — Questions and Answers
Question 1: Which class of drugs is used to reduce intraocular pressure by decreasing aqueous humor production through inhibition of carbonic anhydrase?
- Beta-blockers
- Prostaglandin analogs
- Carbonic anhydrase inhibitors (Correct answer)
- Alpha-2 agonists
Correct answer: Carbonic anhydrase inhibitors
Carbonic anhydrase inhibitors (e.g., dorzolamide, acetazolamide) reduce IOP by inhibiting the enzyme that produces aqueous humor in the ciliary body.
Question 2: A patient presents with angle-closure glaucoma. Which topical agent is CONTRAINDICATED due to risk of further pupillary dilation?
- Pilocarpine
- Tropicamide (Correct answer)
- Timolol
- Dorzolamide
Correct answer: Tropicamide
Tropicamide is a mydriatic/cycloplegic agent that dilates the pupil, which can worsen angle-closure glaucoma by pushing the iris against the trabecular meshwork.
Question 3: Which prostaglandin analog lowers IOP primarily by increasing uveoscleral outflow?
- Timolol
- Latanoprost (Correct answer)
- Brimonidine
- Brinzolamide
Correct answer: Latanoprost
Latanoprost (Xalatan) is a prostaglandin F2α analog that lowers IOP mainly by enhancing uveoscleral aqueous humor outflow.
Question 4: What is the mechanism of action of pilocarpine in the treatment of glaucoma?
- Decreases aqueous humor secretion
- Increases uveoscleral outflow
- Contracts the ciliary muscle to open the trabecular meshwork (Correct answer)
- Blocks beta-adrenergic receptors
Correct answer: Contracts the ciliary muscle to open the trabecular meshwork
Pilocarpine, a cholinergic agonist, contracts the ciliary muscle, which pulls on the scleral spur and opens the trabecular meshwork to enhance aqueous outflow.
Question 5: Which side effect is most commonly associated with topical prostaglandin analogs such as bimatoprost?
- Corneal edema
- Iris heterochromia and eyelash growth (Correct answer)
- Punctate keratitis
- Corneal ulceration
Correct answer: Iris heterochromia and eyelash growth
Prostaglandin analogs like bimatoprost can cause increased iris pigmentation (heterochromia) and enhanced eyelash growth due to melanocyte stimulation.
Question 6: Apraclonidine is an alpha-2 adrenergic agonist used to control acute IOP spikes. What is its primary limitation for long-term use?
- Rebound hypertension
- High rate of tachyphylaxis and ocular allergy (Correct answer)
- Irreversible corneal toxicity
- Systemic beta-blockade
Correct answer: High rate of tachyphylaxis and ocular allergy
Apraclonidine has a high rate of tachyphylaxis (loss of effect) and a significant incidence of ocular allergy, limiting its use to short-term situations.
Question 7: Which systemic side effect is most concerning when using topical timolol in pediatric patients?
- Hyperglycemia
- Bradycardia and bronchospasm (Correct answer)
- Hypertension
- Hepatotoxicity
Correct answer: Bradycardia and bronchospasm
Topical timolol, a non-selective beta-blocker, can cause systemic absorption leading to bradycardia and bronchospasm, which are especially dangerous in children.
AOC Pharmacology Fundamentals 2
Which class of drugs is used to reduce intraocular pressure by decreasing aqueous humor production through inhibition of carbonic anhydrase?