Vision and Ophthalmology Pharmacology and Medications

Question 1

Timolol, a beta-blocker used to treat glaucoma, lowers IOP by:

Accepted Answer

Decreasing aqueous humor production by the ciliary body

Answer

Timolol is a non-selective beta-adrenergic blocker that reduces IOP by decreasing aqueous humor production from the ciliary body epithelium.

Question 2

Prostaglandin analogs (e.g., latanoprost) lower IOP primarily by:

Accepted Answer

Increasing uveoscleral and trabecular outflow

Answer

Prostaglandin analogs are the most potent topical IOP-lowering agents, working primarily by enhancing uveoscleral outflow through the ciliary muscle.

Question 3

Which class of glaucoma medication is contraindicated in patients with sulfonamide allergy?

Accepted Answer

Carbonic anhydrase inhibitors

Answer

Carbonic anhydrase inhibitors (dorzolamide, brinzolamide topically; acetazolamide orally) are sulfonamide derivatives and may cause cross-reactivity in sulfonamide-allergic patients.

Question 4

Tropicamide eye drops are used to dilate the pupil for fundus examination. What is their mechanism?

Accepted Answer

Anticholinergic (muscarinic antagonist)

Answer

Tropicamide blocks muscarinic acetylcholine receptors in the iris sphincter and ciliary muscle, causing mydriasis and cycloplegia.

Question 5

Pilocarpine eye drops are used in acute angle-closure glaucoma. What is their mechanism of action?

Accepted Answer

Stimulate muscarinic receptors to cause miosis and open the drainage angle

Answer

Pilocarpine is a muscarinic agonist that constricts the pupil (miosis) and contracts the ciliary muscle, pulling the peripheral iris away from the trabecular meshwork to open the angle.

Vision and Ophthalmology Practice Test

Vision and Ophthalmology Practice Test

Vision and Ophthalmology Pharmacology and Medications