Ocular Pharmacology and Therapeutics
Core concepts
Know the major drug classes used in ophthalmology: antibiotics, antivirals, antifungals, steroids, NSAIDs, glaucoma medications, and mydriatics/cycloplegics. Understand pharmacokinetics of topical drops, including punctal occlusion to reduce systemic absorption. Learn the side effects of steroids: cataract, glaucoma, and infection risk. Know the difference between mydriatics (phenylephrine) and cycloplegics (atropine, cyclopentolate). Understand the use of anti-VEGF agents and their risks.
Traps
Do not use steroids in herpetic keratitis without antiviral coverage. Be aware of systemic side effects of topical beta-blockers. Recognize that atropine has a long duration and can cause systemic anticholinergic effects. In children, be cautious with strong cycloplegics. Do not forget that topical NSAIDs can cause corneal melting.
Rule of thumb
For any topical drop with systemic risk, recommend punctal occlusion and eyelid closure. Steroids are contraindicated in active infectious keratitis unless specific coverage is given.
Worked example
A patient on topical prednisolone develops increased IOP and a posterior subcapsular cataract. This is steroid-induced; taper the steroid and manage IOP.