What is the treatment for conjunctivitis (pink eye)?

Treatment of Conjunctivitis (Pink Eye)

Treatment depends entirely on the underlying cause: viral conjunctivitis requires only supportive care, bacterial conjunctivitis may benefit from topical antibiotics (though most cases self-resolve), allergic conjunctivitis responds to topical antihistamines with mast cell stabilizers, while gonococcal and chlamydial conjunctivitis mandate systemic antibiotics. 1, 2

Immediate Red Flags Requiring Ophthalmology Referral

You must refer immediately if any of these are present 1, 2:

• Visual loss (suggests corneal involvement or intraocular pathology)
• Moderate to severe pain (indicates possible keratitis, uveitis, or acute angle-closure glaucoma)
• Severe purulent discharge (raises concern for gonococcal infection)
• Corneal involvement (requires specialist management)
• Conjunctival scarring (suggests chronic or cicatricial disease)
• History of HSV eye disease (risk of recurrence requiring specialist care)
• Immunocompromised state (increased risk of atypical or severe infections)
• Recurrent episodes or lack of response to therapy

Viral Conjunctivitis (Most Common Overall)

Viral conjunctivitis accounts for 80% of acute conjunctivitis cases and requires no specific treatment—only supportive care. 3, 4

Clinical Features

• Watery discharge (not purulent) 5
• Burning, gritty sensation 6
• Often bilateral involvement
• May have preauricular lymphadenopathy 4
• Adenovirus causes approximately 80% of viral cases 4

Treatment Approach

• Artificial tears for symptomatic relief 2, 5
• Cold compresses 2, 5
• Topical antihistamines for comfort 5
• Strict hand hygiene to prevent transmission 5, 4

Critical Pitfall

Never use topical corticosteroids indiscriminately—they can prolong adenoviral infections and worsen HSV infections. 2 If you suspect HSV conjunctivitis (vesicular rash on eyelids or nose), refer immediately before considering any steroid use. 1

Bacterial Conjunctivitis (Second Most Common)

Most uncomplicated bacterial conjunctivitis resolves spontaneously in 1-2 weeks without antibiotics, but topical antibiotics can shorten duration and allow earlier return to work/school. 3, 6

Clinical Features Suggesting Bacterial Etiology

• Mucopurulent discharge with eyelids matted shut on waking 5, 3
• Lack of itching 3
• No history of previous conjunctivitis 3
• More common in children 5, 6

Treatment Algorithm

1. For mild cases: Consider watchful waiting or delayed antibiotic prescribing (similar symptom control to immediate treatment) 5

2. For moderate-to-severe cases: Topical broad-spectrum antibiotics 7

   • Moxifloxacin 0.5% three times daily for 5-7 days (first-line fluoroquinolone) 7
   • Alternative options: other fluoroquinolones, aminoglycosides, or bacitracin 7, 8
   • Clean eyelids with warm water before applying medication 7

3. Follow-up: Advise return in 3-4 days if no improvement 1, 2, 7

4. If persistent despite therapy: Obtain conjunctival cultures to rule out MRSA (increasingly common, especially in nursing home residents and resistant to many topical antibiotics) 1, 7

Special Populations

• Elderly patients: Higher risk of MRSA and giant fornix syndrome; require close monitoring 7
• Contact lens wearers: Always treat with antibiotics and refer to ophthalmology to evaluate for corneal ulcers 3, 6
• Infants in NICU: Higher incidence of gram-negative organisms resistant to gentamicin; may require compounded vancomycin 1

Gonococcal Conjunctivitis (Medical Emergency)

Gonococcal conjunctivitis requires systemic antibiotics—topical therapy alone is inadequate. 1, 2

Treatment Protocol

• Systemic antibiotic therapy is mandatory (see specific regimens in ophthalmology guidelines) 1, 2
• Saline lavage for comfort and rapid resolution 1
• Daily follow-up until resolution with visual acuity and slit-lamp examination at each visit 1, 2
• If corneal involvement present, add topical treatment as for bacterial keratitis 1
• Treat sexual contacts concurrently 1, 2
• Consider sexual abuse in children with gonococcal infection 1, 2
• Rule out Neisseria meningitidis before concluding N. gonorrhoeae is responsible 1

Hospitalization

Hospitalization is mandatory for neonatal gonococcal conjunctivitis and may be necessary for severe cases in adults. 2

Chlamydial Conjunctivitis

Chlamydial conjunctivitis requires systemic antibiotics because more than 50% of infants have concurrent infection at other sites (nasopharynx, genital tract, lungs). 1, 2

Clinical Features

• Follicular conjunctivitis persisting for several weeks 1

Treatment Approach

• Systemic antibiotic therapy (topical therapy alone is insufficient) 1, 2
• No data supports adding topical therapy to systemic treatment 1
• Re-evaluate after treatment (treatment failure rate up to 19%) 1
• Treat sexual contacts concurrently 1, 2
• Consider sexual abuse in children 1, 2
• In low-to-middle income countries with limited antibiotic access: povidone-iodine 1.25% ophthalmic solution 1, 2

Allergic Conjunctivitis

Topical antihistamines with mast cell-stabilizing properties are the treatment of choice for allergic conjunctivitis. 2, 3

Clinical Features

• Itching is the most consistent sign 3, 9
• Bilateral involvement 5
• Watery discharge 5
• Mucoid discharge, chemosis, eyelid edema 9
• Encountered in up to 40% of population 3

Treatment Algorithm

1. First-line measures 2:

   • Wearing sunglasses as barriers to airborne allergens
   • Cold compresses
   • Refrigerated artificial tears

2. Pharmacologic treatment 2, 3:

   • Topical antihistamines with mast cell-stabilizing properties (treatment of choice)
   • For persistent/recurrent cases: mast cell stabilizers alone

3. Severe cases 2:

   • Brief course (1-2 weeks) of topical corticosteroids with low side-effect profile
   • Use cautiously and for limited duration only

4. Identify and avoid allergen triggers 2

Neonatal Conjunctivitis (Ophthalmia Neonatorum)

Erythromycin ophthalmic ointment is used for prophylaxis of ophthalmia neonatorum due to N. gonorrhoeae or C. trachomatis. 10

Critical Considerations

• For infants born to mothers with clinically apparent gonorrhea: intravenous or intramuscular aqueous crystalline penicillin G (50,000 units for term infants, 20,000 units for low birth weight)—topical prophylaxis alone is inadequate 10
• Effectiveness against penicillinase-producing N. gonorrhoeae is not established 10

Prevention and Hygiene Measures

• Strict hand hygiene and frequent handwashing to prevent transmission 7, 5
• Do not share towels, pillows, or cosmetics 2
• Contact lens wearers must discontinue use until complete resolution 2