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

Treatment for Pink Eye (Conjunctivitis)

Treatment depends entirely on the etiology: use supportive care alone for viral conjunctivitis, topical antibiotics for bacterial conjunctivitis only if moderate-to-severe, and topical antihistamine/mast cell stabilizers for allergic conjunctivitis. 1

Determine the Etiology First

You must differentiate between viral, bacterial, and allergic causes before initiating treatment, as indiscriminate antibiotic or corticosteroid use causes harm 1, 2:

Viral conjunctivitis presents with watery discharge, follicular reaction on inferior tarsal conjunctiva, preauricular lymphadenopathy, often starts unilateral then becomes bilateral, and may have concurrent upper respiratory infection 2

Bacterial conjunctivitis shows mucopurulent discharge with matted eyelids upon waking, papillary (not follicular) reaction, can be unilateral or bilateral, and lacks itching 2, 3

Allergic conjunctivitis is characterized by bilateral itching (the most consistent distinguishing feature), watery discharge, no preauricular lymphadenopathy, and often concurrent allergic rhinitis or asthma 2, 4

Viral Conjunctivitis Treatment

Do not prescribe antibiotics for viral conjunctivitis—they provide zero benefit and cause unnecessary toxicity and resistance. 1, 2

Supportive Care Only

• Refrigerated preservative-free artificial tears four times daily to dilute viral particles and inflammatory mediators 1
• Cold compresses for symptomatic relief 1
• Topical antihistamines (second-generation) for itching and discomfort 1
• Strict hand hygiene with soap and water to prevent transmission 1
• Avoid close contact for 7-14 days from symptom onset 1

Special Viral Subtypes Requiring Different Management

Herpes Simplex Virus (HSV) conjunctivitis requires topical ganciclovir 0.15% gel or trifluridine 1% solution, plus oral antivirals (acyclovir, valacyclovir, or famciclovir) 1. Never use topical corticosteroids in HSV without antiviral coverage, as they potentiate viral replication and can cause corneal perforation. 1

Severe adenoviral conjunctivitis with marked chemosis, severe lid swelling, epithelial sloughing, or membranous conjunctivitis may warrant a brief 1-2 week course of low side-effect profile topical corticosteroids (loteprednol, fluorometholone, or rimexolone), but requires close monitoring for elevated intraocular pressure and cataract 5, 1

Bacterial Conjunctivitis Treatment

Mild bacterial conjunctivitis is self-limited and resolves spontaneously in most cases, but topical antibiotics provide earlier clinical remission (62% cured by days 3-5 vs 28% with placebo) and allow faster return to work or school. 1, 6

First-Line Topical Antibiotics

Use topical moxifloxacin 0.5% three times daily for 5-7 days as the preferred first-line treatment for uncomplicated bacterial conjunctivitis, offering superior gram-positive coverage including some MRSA strains. 1

Alternative options if fluoroquinolones unavailable 1:

• Erythromycin ointment 1 cm applied to infected eye(s) up to six times daily 7
• Polymyxin B/trimethoprim drops
• Bacitracin ointment applied 1-3 times daily 8
• Ofloxacin 0.3% four times daily for 5-7 days

No single antibiotic demonstrates superiority over others for uncomplicated cases, so choose based on dosing convenience, cost, and local resistance patterns. 1

Special Bacterial Subtypes Requiring Systemic Treatment

Gonococcal conjunctivitis requires ceftriaxone 250 mg IM single dose PLUS azithromycin 1 g oral single dose, with daily monitoring until resolution, as it can cause corneal perforation if untreated 1. Obtain conjunctival cultures and Gram staining before initiating treatment 1.

Chlamydial conjunctivitis requires azithromycin 1 g oral single dose OR doxycycline 100 mg oral twice daily for 7 days, as topical therapy alone fails because Chlamydia trachomatis causes intracellular infection requiring systemic penetration 1. Screen for concurrent genital infections and treat sexual partners 1.

Suspected MRSA conjunctivitis unresponsive to moxifloxacin within 48-72 hours may require compounded topical vancomycin 1

Allergic Conjunctivitis Treatment

Use dual-action topical agents (antihistamine + mast cell stabilizer) such as olopatadine or ketotifen as first-line therapy, providing rapid onset for acute symptoms while preventing recurrent episodes. 4

First-Line Treatment Algorithm

• Topical antihistamine/mast cell stabilizers (olopatadine, ketotifen, epinastine, or azelastine) 5, 4
• Refrigerated preservative-free artificial tears four times daily to dilute allergens 5, 4
• Cold compresses for inflammation reduction 4
• Allergen avoidance: hypoallergenic bedding, eyelid cleansers, frequent clothes washing, showering before bed 5
• Avoid eye rubbing (can lead to keratoconus in atopic patients) 5, 4

Second-Line Treatment (If Symptoms Persist After 48 Hours)

Add a brief 1-2 week course of low side-effect profile topical corticosteroids (loteprednol etabonate) if symptoms do not improve with dual-action agents. 5, 4 Monitor intraocular pressure baseline and periodically, and perform pupillary dilation to evaluate for cataract 5, 4.

Third-Line Treatment (Severe/Refractory Cases)

Topical cyclosporine 0.05% at least four times daily or tacrolimus for severe cases not responding to above therapies 5, 4. Cyclosporine 0.1% is FDA-approved specifically for vernal keratoconjunctivitis in children and adults 5.

Critical Pitfalls to Avoid in Allergic Conjunctivitis

Avoid oral antihistamines as primary therapy—they worsen dry eye syndrome and disrupt the protective tear film barrier. 5, 4 Avoid chronic vasoconstrictor use beyond 10 days, as it causes rebound hyperemia 5, 4. Never use topical antibiotics for allergic conjunctivitis, as they cause unnecessary toxicity 4.

Red Flags Requiring Immediate Ophthalmology Referral

Refer urgently if any of the following are present 1, 2:

• Visual loss or decreased vision
• Moderate or severe pain
• Severe purulent discharge
• Corneal involvement (infiltrate, ulcer, opacity)
• Conjunctival scarring
• Lack of response to therapy after 3-4 days
• Recurrent episodes
• History of HSV eye disease
• Immunocompromised state
• Neonatal conjunctivitis (requires systemic treatment coordinated with pediatrician) 1

Special Pediatric Considerations

Fluoroquinolones (besifloxacin, levofloxacin, gatifloxacin, ciprofloxacin, moxifloxacin, ofloxacin) are approved for conjunctivitis in children older than 12 months. 1

Neonatal chlamydial conjunctivitis requires erythromycin base or ethylsuccinate 50 mg/kg/day oral divided into 4 doses for 14 days, as more than 50% have infection at other sites 1. Monitor for infantile hypertrophic pyloric stenosis in infants less than 6 weeks receiving oral erythromycin 1.

Neonatal gonococcal conjunctivitis requires ceftriaxone 25-50 mg/kg IV or IM single dose 1. Consider sexual abuse in children with gonococcal or chlamydial conjunctivitis 1.