Eye Drops for Pink Eye (Conjunctivitis)
The recommended eye drops depend entirely on the type of conjunctivitis: for allergic conjunctivitis, use dual-action antihistamine/mast cell stabilizers like olopatadine or ketotifen as first-line treatment; for bacterial conjunctivitis, topical antibiotics like erythromycin or bacitracin can be used but are often unnecessary as most cases self-resolve; for viral conjunctivitis, no specific eye drops are needed—only supportive care with artificial tears. 1, 2, 3, 4, 5
Determining the Type of Conjunctivitis
The clinical presentation guides treatment selection:
- Bacterial conjunctivitis: Mucopurulent discharge with eyelids matted shut upon waking, lack of itching, no history of prior conjunctivitis 4, 6, 5
- Viral conjunctivitis: Watery discharge, burning/gritty sensation, often bilateral, may have preauricular lymphadenopathy 4, 5
- Allergic conjunctivitis: Bilateral itching (most consistent sign), watery discharge, seasonal pattern 1, 4, 5
Treatment Algorithm by Type
Allergic Conjunctivitis
First-line treatment:
- Dual-action antihistamine/mast cell stabilizers are the most effective first-line option: olopatadine, ketotifen, epinastine, or azelastine provide both immediate relief and ongoing protection 1, 7
- Ketotifen: 1 drop in affected eye(s) twice daily (every 8-12 hours) for adults and children ≥3 years 7
- Store drops in refrigerator for additional cooling relief 1
Adjunctive non-pharmacological measures:
- Cold compresses for immediate symptomatic relief 1, 4
- Refrigerated preservative-free artificial tears 4 times daily to dilute allergens 1
- Wear sunglasses as physical barrier against airborne allergens 1
- Avoid eye rubbing (can lead to keratoconus in atopic patients) 1
If inadequate response after 48 hours:
- Add loteprednol etabonate (low side-effect corticosteroid) for 1-2 weeks maximum 1, 8
- Critical: Measure baseline intraocular pressure and perform periodic monitoring plus pupillary dilation to evaluate for glaucoma and cataract 1
Severe or refractory cases:
- Topical cyclosporine 0.05% at least 4 times daily for vernal or atopic keratoconjunctivitis 1
- Topical tacrolimus 0.03% or 0.1% as alternative 1
Critical pitfalls to avoid:
- Never use punctal plugs in allergic conjunctivitis—they prevent flushing of allergens from the ocular surface 1
- Avoid chronic vasoconstrictor use (>10 days causes rebound hyperemia) 1
- Avoid oral antihistamines as primary treatment—they worsen dry eye 1
Bacterial Conjunctivitis
Most cases are self-limiting and resolve in 1-2 weeks without treatment 4, 5
When antibiotics are indicated:
- Contact lens wearers (must treat and refer for corneal ulcer evaluation) 4, 6
- Gonococcal or chlamydial conjunctivitis (requires systemic antibiotics plus topical therapy) 5
- Neonatal conjunctivitis 6
Topical antibiotic options:
- Erythromycin ointment: Apply approximately 1 cm directly to infected eye(s) up to 6 times daily depending on severity 3
- Bacitracin ointment: Apply directly into conjunctival sac 1-3 times daily 2
- Delayed antibiotic prescribing has similar symptom control as immediate prescribing in uncomplicated cases 4
Important caveat: Topical antibiotics can induce toxicity and contribute to antibiotic resistance—use judiciously 1
Viral Conjunctivitis
No specific antiviral eye drops are needed—treatment is entirely supportive 4, 5
Supportive care options:
- Artificial tears for lubrication 4, 9
- Cold compresses 4
- Topical antihistamine drops for symptomatic relief 4
Evidence note: One study showed dexamethasone 0.1%/povidone-iodine 0.4% reduced duration by 2.4 days compared to artificial tears, but caused more stinging 9. However, this is not standard practice and corticosteroids carry risks of elevated intraocular pressure and secondary infection 1.
Critical infection control: Strict handwashing is essential to prevent transmission 4
When to Refer to Ophthalmology
Immediate referral indicated for:
- Neonatal conjunctivitis 4
- Severe pain or decreased vision 4
- Recent ocular surgery 4
- Vesicular rash on eyelids or nose (suggests herpes) 4
- Immunocompromised state 4
- Contact lens wearers with suspected bacterial conjunctivitis 6
- Children <7 years requiring corticosteroids 10
- Symptoms not improving after 48 hours on appropriate therapy 1