Ocular Pharmacology: High-Yield Guide for Residents
Last updated: October 2026
You will prescribe eye drops every day of your career. This page summarises the drug groups residents use most, how they work, and the side effects and contraindications that examiners and patients care about.
Glaucoma medications
| Class (examples) | Mechanism | Key side effects / cautions |
|---|---|---|
| Prostaglandin analogues (latanoprost, bimatoprost, travoprost) | Increase uveoscleral outflow | Once daily at night. Iris darkening, eyelash growth, periorbital fat atrophy, conjunctival redness. Use with caution in active uveitis and eyes at risk of CME. |
| Beta-blockers (timolol, betaxolol) | Reduce aqueous production | Bronchospasm, bradycardia, heart block. Avoid in asthma, COPD and heart block; betaxolol (cardioselective) is safer for the lungs but less effective. |
| Alpha-2 agonists (brimonidine, apraclonidine) | Reduce aqueous production and increase uveoscleral outflow | Allergic follicular conjunctivitis, dry mouth, fatigue. Avoid brimonidine in infants and young children because of CNS depression. |
| Carbonic anhydrase inhibitors (topical dorzolamide, brinzolamide; oral acetazolamide) | Reduce aqueous production | Topical: stinging, bitter taste. Oral: tingling, fatigue, kidney stones, low potassium, sulfa-type allergy. |
| Rho kinase inhibitors (netarsudil) | Increase trabecular outflow | Conjunctival redness, corneal verticillata, small subconjunctival haemorrhages. |
| Miotics (pilocarpine) | Increase trabecular outflow; pull the iris away from the angle | Brow ache, dim vision, myopic shift, and a small risk of retinal detachment. |
| Hyperosmotic agents (IV mannitol, oral glycerol) | Draw fluid out of the vitreous | Emergency use only. Caution in heart and kidney failure; oral glycerol raises blood sugar. |
Fixed combinations reduce the number of drops and improve adherence. See also AAO cap colour codes.
Corticosteroids
- Prednisolone acetate 1% and dexamethasone are potent. Fluorometholone and loteprednol carry a lower risk of raising IOP.
- Steroid response: IOP may rise after a few weeks of use; check IOP regularly in anyone on long-term steroids.
- Long-term use causes posterior subcapsular cataract and increases the risk of infection.
- Never give topical steroids for an undiagnosed red eye: they can make herpes simplex and fungal keratitis much worse.
NSAIDs
- Ketorolac, nepafenac and bromfenac are used to reduce inflammation and the risk of cystoid macular oedema after cataract surgery.
- Long-term or excessive use can cause corneal melting, especially in dry or compromised corneas.
Anti-infectives
- Fluoroquinolones (moxifloxacin, gatifloxacin): broad-spectrum; first choice for many bacterial infections and prophylaxis.
- Aminoglycosides (tobramycin, gentamicin): good Gram-negative cover, but toxic to the epithelium with frequent use.
- Fortified antibiotics for severe bacterial keratitis (commonly prepared): cefazolin 50 mg/mL with tobramycin 14 mg/mL; vancomycin for resistant Gram-positive organisms. See microbial keratitis.
- Antifungals: natamycin 5% for filamentous fungi (first choice for Fusarium, per MUTT I); amphotericin B 0.15% for yeasts; voriconazole 1% as an alternative.
- Antivirals: acyclovir 3% ointment or ganciclovir 0.15% gel for HSV epithelial keratitis; oral acyclovir or valacyclovir for stromal disease prophylaxis and zoster.
- Intravitreal doses are listed in intravitreal dosage.
Mydriatics and cycloplegics
| Drug | Use | Notes |
|---|---|---|
| Tropicamide | Routine dilation | Short-acting; weak cycloplegia |
| Phenylephrine 2.5% / 10% | Dilation (adds to tropicamide) | 10% can raise blood pressure; prefer 2.5% in infants and patients with cardiovascular disease |
| Cyclopentolate | Cycloplegic refraction in children | Can cause CNS side effects (hallucinations, ataxia), especially in young children |
| Atropine | Strongest cycloplegia; uveitis; amblyopia penalisation; low-dose for myopia control | Effect can last up to about two weeks; watch for systemic toxicity in children |
Systemic drugs with ocular side effects
| Drug | Ocular effect | What to do |
|---|---|---|
| Hydroxychloroquine | Bull's-eye maculopathy (often pericentral in Asian patients) | Keep the dose at or below 5 mg/kg of real body weight per day; baseline exam, then annual screening after 5 years (sooner if high risk) with OCT and visual fields |
| Ethambutol | Optic neuropathy (central scotoma, colour vision loss) | Baseline and regular checks of vision and colour vision; stop the drug if it occurs |
| Tamsulosin and other alpha-1 blockers | Intraoperative floppy iris syndrome | Always ask before cataract surgery; stopping the drug does not reliably prevent it |
| Topiramate | Bilateral acute angle closure from ciliochoroidal effusion, with a myopic shift | Stop the drug. Laser iridotomy does not help, because the mechanism is not pupil block. |
| Amiodarone | Vortex keratopathy; rarely optic neuropathy | Keratopathy rarely affects vision |
| Systemic corticosteroids | Cataract, raised IOP, CSCR | Monitor IOP and lens; ask about all routes, including inhalers and creams |
| Vigabatrin | Concentric visual field loss | Visual field monitoring |
Related: types of eye drops explained (patient guide) and landmark trials.
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Looking for an eye specialist in Ahmedabad? Read our patient guide to eye drops or book a consultation with Dr. Dhaval Patel.