What is the recommended treatment for a patient presenting with conjunctivitis (pink eye)?

Treatment of Conjunctivitis (Pink Eye)

The treatment of conjunctivitis depends entirely on the underlying etiology: viral conjunctivitis requires only supportive care with artificial tears and cold compresses, bacterial conjunctivitis may benefit from topical antibiotics (though mild cases are self-limited), and allergic conjunctivitis responds best to dual-action topical antihistamine/mast cell stabilizers like olopatadine or ketotifen. 1

Step 1: Determine the Etiology Based on Clinical Presentation

The key to appropriate treatment is accurate diagnosis, as indiscriminate antibiotic use should be avoided 1:

Viral Conjunctivitis Features:

• Watery discharge with abrupt onset, often starting unilateral but becoming sequentially bilateral 1
• Follicular reaction on the inferior tarsal conjunctiva (not papillary) 1
• Preauricular lymphadenopathy, especially with adenoviral infections 1
• Concurrent upper respiratory infection symptoms 1
• May have subconjunctival hemorrhages, chemosis, and eyelid swelling 1
• Self-limited course, typically resolving within 5-14 days 1

Bacterial Conjunctivitis Features:

• Mucopurulent discharge with matted eyelids upon waking 1, 2
• Papillary reaction (not follicular) 1
• Can be unilateral or bilateral 1
• Lack of itching and no history of prior conjunctivitis favor bacterial etiology 3
• May be associated with concurrent otitis media, sinusitis, or pharyngitis in children 1

Allergic Conjunctivitis Features:

• Itching is the most consistent and distinguishing feature 1, 3
• Bilateral presentation with watery discharge 1
• Often seasonal or perennial depending on allergen exposure 1
• Absence of preauricular lymphadenopathy and matted eyelids 1
• May have concurrent allergic rhinitis or asthma 1

Step 2: Treatment by Etiology

Viral Conjunctivitis Management

Avoid antibiotics entirely, as they provide no benefit and may cause unnecessary toxicity 1:

• Artificial tears (preferably preservative-free and refrigerated) for symptomatic relief, used four times daily 1
• Cold compresses to reduce inflammation 1
• Topical antihistamines for symptomatic relief if needed 1
• Patient education about high contagiousness: minimize contact with others for 10-14 days from symptom onset 1
• Strict hand hygiene with soap and water, avoid sharing towels/pillows, disinfect surfaces 1, 2

For severe cases with marked chemosis, lid swelling, or pseudomembranes: Consider a short course of topical corticosteroids (e.g., loteprednol) with close ophthalmology follow-up 1. However, corticosteroids require baseline and periodic intraocular pressure monitoring and pupillary dilation to evaluate for glaucoma and cataracts 4, 1. Critical warning: Corticosteroids may prolong viral shedding and can worsen herpes simplex virus infections 1.

Bacterial Conjunctivitis Management

Mild bacterial conjunctivitis is usually self-limited and may resolve without specific treatment 1:

• Most uncomplicated cases resolve in 1-2 weeks without intervention 3
• For moderate to severe cases: A 5-7 day course of broad-spectrum topical antibiotic is usually effective 1
• No specific antibiotic agent has demonstrated superiority—choose the most convenient or least expensive option 1
• Common options include polymyxin-bacitracin ointment 5, 6 or erythromycin ointment 5, applied 1-6 times daily depending on severity 5, 7
• Topical antibiotics shorten the duration of clinical disease and enhance bacterial eradication 6

Special bacterial cases requiring systemic treatment:

• Gonococcal conjunctivitis: Requires systemic therapy in addition to topical treatment, with hospitalization for parenteral therapy, daily follow-up, and treatment of sexual contacts 1
• Chlamydial conjunctivitis: Requires systemic treatment (topical therapy alone is inadequate) and evaluation/treatment of sexual partners 1

Allergic Conjunctivitis Management

First-line therapy: Dual-action topical agents (antihistamine + mast cell stabilizer) 8:

• Olopatadine, ketotifen, epinastine, or azelastine provide rapid onset and treat acute symptoms while preventing recurrence 8
• Environmental modifications: Wear sunglasses as barrier to airborne allergens, use cold compresses, apply refrigerated preservative-free artificial tears four times daily 8, 9
• Avoid eye rubbing, as it worsens symptoms and can lead to keratoconus, especially in atopic patients 8, 9
• Allergen avoidance strategies: hypoallergenic bedding, frequent clothes washing, showering before bed 8

For inadequate response within 48 hours:

• Short course (1-2 weeks) of topical corticosteroids with low side-effect profile (e.g., loteprednol) 8
• Requires baseline and periodic intraocular pressure monitoring and pupillary dilation 8

For refractory cases:

• Topical immunomodulators (cyclosporine 0.05% or tacrolimus) 8
• Consider referral to allergist for immunotherapy 8

Step 3: Red Flags Requiring Urgent Ophthalmology Referral

Refer immediately if any of the following are present 1:

• Visual loss or decreased vision
• Moderate or severe pain
• Severe purulent discharge (concern for gonococcal infection)
• Corneal involvement (infiltrate, ulcer, or dendritic lesions)
• Conjunctival scarring
• Lack of response to therapy
• History of herpes simplex virus eye disease
• Immunocompromised state
• Neonatal conjunctivitis (requires prompt evaluation and may need hospitalization)
• Contact lens wearers (evaluate for corneal ulcers) 10

Step 4: Follow-Up Recommendations

• Viral conjunctivitis: Re-evaluate within 1 week if severe; return if symptoms persist beyond 2-3 weeks 1
• Bacterial conjunctivitis: Follow up if no improvement within 5-7 days of antibiotic therapy 1
• Allergic conjunctivitis: Reassess within 48-72 hours to confirm symptom improvement 8
• Patients on topical corticosteroids: Regular monitoring of intraocular pressure and periodic pupillary dilation 4, 1

Critical Pitfalls to Avoid

• Never use antibiotics for viral conjunctivitis—they provide no benefit and cause unnecessary toxicity 1
• Avoid indiscriminate use of topical corticosteroids without ophthalmology follow-up, as they can elevate intraocular pressure, cause cataracts, prolong adenoviral infections, and worsen HSV infections 1
• Do not use punctal plugs in allergic conjunctivitis, as they prevent flushing of allergens and inflammatory mediators 8
• Avoid chronic use of topical vasoconstrictors (>10 days), which can cause rebound hyperemia 8
• Do not miss gonococcal conjunctivitis, as it can cause corneal perforation and requires immediate systemic treatment 1
• Avoid contact lens wear during any form of infectious conjunctivitis 1