What is the best course of treatment for a patient with ongoing conjunctivitis (pink eye)?

Treatment of Ongoing Conjunctivitis

For ongoing conjunctivitis, first determine the etiology through specific clinical features—watery discharge with follicles suggests viral (supportive care only), mucopurulent discharge with matted eyelids indicates bacterial (topical moxifloxacin 0.5% three times daily for 5-7 days), and itching with mucoid discharge points to allergic (topical antihistamine/mast cell stabilizers)—then escalate to systemic antibiotics only if gonococcal or chlamydial infection is suspected. 1

Diagnostic Algorithm for Persistent Conjunctivitis

Key Clinical Features to Differentiate Etiology

Viral conjunctivitis indicators:

• Watery or serofibrinous discharge 2
• Follicular reaction on palpebral conjunctiva 1
• Preauricular lymphadenopathy 1
• Bilateral presentation (often starts unilateral then spreads) 2
• Recent upper respiratory infection or sick contacts 3

Bacterial conjunctivitis indicators:

• Mucopurulent discharge with eyelids matted shut on waking 3, 4
• Lack of itching 4
• No history of previous conjunctivitis 4
• More commonly unilateral or asymmetric 1

Allergic conjunctivitis indicators:

• Itching is the most consistent sign 4, 5
• Mucoid discharge 5
• Chemosis and eyelid edema 5
• Concurrent allergic rhinitis or asthma 1
• Bilateral presentation 1

Red Flags Requiring Immediate Ophthalmology Referral

Refer urgently if any of the following are present:

• Visual loss or decreased vision 1, 3
• Moderate to severe pain not relieved by topical anesthetics 1, 6
• Severe purulent discharge (suggests gonococcal infection) 1
• Corneal involvement (infiltrate, ulcer, opacity, or epithelial defects) 1, 3
• History of HSV eye disease 1
• Immunocompromised state 1, 3
• Vesicular rash on eyelids or nose (suggests herpes zoster) 3
• Recent ocular surgery 3
• Conjunctival scarring or lack of response to therapy 1

Treatment by Etiology

Viral Conjunctivitis Management

Adenoviral conjunctivitis (most common, 80% of viral cases):

• Supportive care only—refrigerated preservative-free artificial tears four times daily 1
• Cold compresses for symptomatic relief 1, 3
• Topical antihistamines for itching and discomfort 1
• Avoid topical antibiotics as they provide no benefit and risk adverse effects and resistance 1
• Strict hand hygiene with soap and water to prevent transmission 1
• Avoid close contact for 7-14 days from symptom onset 1

Topical corticosteroids may be considered only in severe cases with:

• Marked chemosis 1
• Severe lid swelling 1
• Epithelial sloughing 1
• Membranous conjunctivitis 1
• Requires close monitoring for elevated intraocular pressure and cataract 1

HSV conjunctivitis:

• Topical ganciclovir 0.15% gel three to five times daily OR trifluridine 1% solution five to eight times daily 1
• Add oral antivirals (acyclovir, valacyclovir, or famciclovir) 1
• Never use topical corticosteroids without antiviral coverage as they potentiate viral replication 1
• Prolonged trifluridine use beyond 2 weeks causes epithelial toxicity 1

Bacterial Conjunctivitis Management

First-line treatment for uncomplicated bacterial conjunctivitis:

• Topical moxifloxacin 0.5% three times daily for 5-7 days 1
• Provides superior gram-positive coverage including some MRSA strains 1
• Achieves 81% complete resolution at 48 hours and 84-94% microbiological eradication 1

Alternative topical antibiotics if moxifloxacin unavailable:

• Ofloxacin 0.3% four times daily for 5-7 days 1
• Levofloxacin 0.5% (superior to ofloxacin in children) 1
• Gentamicin or tetracycline 1

Important caveat: Mild bacterial conjunctivitis is self-limited, resolving spontaneously in 64% of cases by days 6-10 without treatment 1. However, topical antibiotics provide earlier clinical remission (68.2% vs 55.5% with placebo by days 4-9) and allow faster return to work or school 1.

If no improvement in 48-72 hours, consider:

• MRSA infection—may require compounded topical vancomycin 1
• Gonococcal or chlamydial infection—requires systemic antibiotics 1
• Obtain conjunctival cultures and Gram staining 1

Gonococcal and Chlamydial Conjunctivitis (Requires Systemic Treatment)

Gonococcal conjunctivitis in adults:

• Ceftriaxone 250 mg IM single dose PLUS azithromycin 1 g oral single dose 1
• Daily monitoring until resolution 1
• Can cause corneal perforation if untreated 1
• Obtain conjunctival cultures and Gram staining before treatment 1

Chlamydial conjunctivitis in adults:

• Azithromycin 1 g oral single dose OR doxycycline 100 mg oral twice daily for 7 days 1
• Topical therapy alone fails because Chlamydia causes intracellular infection requiring systemic penetration 1

Critical considerations:

• Screen for concurrent genital infections and treat sexual partners 1
• Consider sexual abuse in children with gonococcal or chlamydial conjunctivitis 1
• Retest approximately 3 months after treatment 1

Neonatal gonococcal conjunctivitis:

• Ceftriaxone 25-50 mg/kg IV or IM single dose 1
• Requires immediate pediatric consultation 1

Neonatal chlamydial conjunctivitis:

• Erythromycin base or ethylsuccinate 50 mg/kg/day oral divided into 4 doses for 14 days 1, 7
• Monitor for infantile hypertrophic pyloric stenosis in infants <6 weeks 1
• More than 50% have concurrent infection at other sites, necessitating systemic therapy 1

Allergic Conjunctivitis Management

First-line treatment:

• Second-generation topical antihistamines with mast cell-stabilizing properties 1
• Examples include olopatadine, ketotifen, or azelastine 1

Adjunctive measures:

• Cold compresses 1
• Refrigerated preservative-free artificial tears 1
• Sunglasses as allergen barrier 1

Second-line treatment if symptoms persist:

• Brief 1-2 week course of low side-effect profile topical corticosteroids (e.g., loteprednol 0.5%) 1
• Monitor intraocular pressure and for cataract 1

Avoid:

• Chronic use of topical vasoconstrictors (cause rebound vasodilation) 1
• Oral antihistamines (may worsen dry eye and exacerbate allergic conjunctivitis) 1

Contact Lens-Related Keratoconjunctivitis

Immediate management:

• Discontinue contact lens wear until cornea returns to normal 8
• Brief 1-2 week course of topical corticosteroids 8
• Longer-term topical cyclosporine 0.05% 8

At follow-up, review:

• Contact lens fit, type, and care regimen 8
• Consider nonpreserved lens care systems, daily disposable lenses, high DK/T ratio materials 8
• Consider alternatives to contact lenses (eyeglasses or refractive surgery) once resolved 8

Giant Papillary Conjunctivitis

Treatment approach:

• Discontinue contact lens use in conjunction with topical anti-inflammatory agents 8
• Replace lenses more frequently or switch to daily disposable lenses 8
• Use preservative-free lens care systems 8
• Administer mast-cell stabilizing agents 8
• Treat associated aqueous tear deficiency and meibomian gland dysfunction 8

If corticosteroids used:

• Measure intraocular pressure at baseline and periodically 8
• Perform pupillary dilation to evaluate for cataract 8

Common Pitfalls and How to Avoid Them

Pitfall 1: Using topical antibiotics for viral conjunctivitis

• Viral conjunctivitis (80% of acute cases) does not respond to antibacterial agents 1
• Antibiotics induce toxicity and promote resistance 1
• Solution: Confirm viral etiology through watery discharge, follicles, and preauricular lymphadenopathy before withholding antibiotics 1

Pitfall 2: Using topical corticosteroids in HSV conjunctivitis without antiviral coverage

• Corticosteroids potentiate HSV infection and worsen outcomes 1
• Solution: Always add topical or oral antivirals when treating HSV conjunctivitis 1

Pitfall 3: Treating gonococcal or chlamydial conjunctivitis with topical antibiotics alone

• Topical therapy fails because these organisms require systemic bactericidal levels 1
• Delayed referral leads to poor outcomes including vision loss 1
• Solution: Obtain cultures if severe purulent discharge present, and initiate systemic antibiotics immediately 1

Pitfall 4: Failing to consider sexual abuse in children with gonococcal or chlamydial conjunctivitis

• This has serious legal and child protection consequences 1
• Solution: Document diagnosis by standard culture and involve appropriate authorities 1

Pitfall 5: Prescribing oral antibiotics for routine bacterial conjunctivitis

• Oral antibiotics are reserved exclusively for gonococcal and chlamydial conjunctivitis 1
• Unnecessary systemic exposure promotes resistance and causes adverse effects 1
• Solution: Use topical antibiotics or supportive care alone for routine bacterial conjunctivitis 1

Pitfall 6: Missing medication-induced or preservative-induced keratoconjunctivitis

• Chronic conjunctivitis may be caused by topical glaucoma medications or preservatives 8
• Solution: Review all topical medications and consider switching to preservative-free formulations 8