What are the treatment options for an adult patient with no significant medical history presenting with allergic, bacterial, or viral conjunctivitis?

Treatment of Conjunctivitis: Allergic vs Bacterial vs Viral

The treatment approach for conjunctivitis depends entirely on the etiology: viral conjunctivitis requires only supportive care without antibiotics, bacterial conjunctivitis may benefit from topical antibiotics in moderate-to-severe cases, and allergic conjunctivitis responds to topical antihistamines with mast cell-stabilizing activity. 1

Initial Diagnostic Differentiation

Viral Conjunctivitis Features

• Watery discharge with follicular reaction on the inferior tarsal conjunctiva 2, 3
• Often starts unilateral but becomes sequentially bilateral 2
• Preauricular lymphadenopathy commonly present 2, 3
• May have concurrent upper respiratory infection 2
• Subconjunctival hemorrhages, chemosis, and eyelid swelling can occur 2

Bacterial Conjunctivitis Features

• Mucopurulent discharge with matted eyelids on waking 2, 3, 4
• Papillary (not follicular) conjunctival reaction 2
• Lack of itching 4
• May be associated with otitis media, sinusitis, or pharyngitis in children 1, 2
• Preauricular lymphadenopathy less common unless hypervirulent organisms 2

Allergic Conjunctivitis Features

• Itching is the most consistent and distinguishing feature 2, 4
• Bilateral presentation 2
• Watery discharge with mild mucous component 2
• History of atopy, asthma, or eczema 2
• Absence of preauricular lymphadenopathy and matted eyelids 2

Treatment by Etiology

Viral Conjunctivitis Management

Antibiotics should NOT be prescribed for viral conjunctivitis—they provide no benefit and may cause unnecessary toxicity. 1, 2

Supportive care includes:

• Artificial tears for symptomatic relief 2, 3
• Cold compresses 2
• Topical antihistamines for symptomatic relief 1
• Self-limited course, typically resolving within 5-14 days 5, 2

Patient education is critical:

• Highly contagious for 10-14 days from symptom onset 2
• Frequent handwashing with soap and water 2
• Avoid sharing towels and pillows 2
• Avoid touching eyes 2

Topical corticosteroids may be considered for severe cases with marked chemosis and lid swelling, but require close ophthalmology follow-up for monitoring intraocular pressure and cataract formation. 2 Corticosteroids may prolong viral shedding and worsen HSV infections. 2

Bacterial Conjunctivitis Management

Mild bacterial conjunctivitis is usually self-limited and may resolve without treatment, but topical antibiotics may decrease the duration of infection. 1, 2

For moderate to severe bacterial conjunctivitis:

• 5-7 day course of broad-spectrum topical antibiotic 1, 2
• No evidence demonstrates superiority of any particular topical antibiotic agent 1
• Options include erythromycin ointment, polymyxin B/trimethoprim drops, or fluoroquinolones 2
• Moxifloxacin 0.5% ophthalmic solution: one drop in affected eye 3 times daily for 7 days 6

Common pitfall: Indiscriminate use of topical antibiotics should be avoided as viral conjunctivitis will not respond to antibacterial agents. 1

Allergic Conjunctivitis Management

Topical antihistamines with mast cell-stabilizing activity are first-line treatment. 2, 4

Treatment options include:

• Olopatadine or ketotifen 2
• Environmental modifications: wearing sunglasses as barrier to airborne allergens 2
• Cold compresses and refrigerated artificial tears 2
• Avoid eye rubbing 2

For refractory cases:

• Short-term corticosteroids (brief 1-2 week course with low side-effect profile) 2
• Allergen-specific immunotherapy beneficial in reducing symptoms, more so in children than adults 2

Critical Red Flags Requiring Immediate Ophthalmology Referral

Refer urgently if any of the following are present: 2

• Visual loss or decreased vision
• Moderate or severe pain
• Severe purulent discharge
• Corneal involvement (always examine cornea with fluorescein staining in purulent conjunctivitis) 5
• Conjunctival scarring
• Lack of response to therapy
• Recurrent episodes
• History of HSV eye disease
• Immunocompromised state

Special High-Risk Situations

Gonococcal conjunctivitis:

• Can cause corneal perforation within 24-48 hours 5
• Requires immediate systemic antibiotics in addition to topical therapy 5, 2
• Presents with marked eyelid edema, marked purulent discharge, and preauricular lymphadenopathy 1, 2

Chlamydial conjunctivitis:

• Requires systemic treatment and evaluation of sexual partners 2
• Topical therapy alone is inadequate 2
• Distinctive sign: follicles on bulbar conjunctiva and semilunar fold 5

Neonatal conjunctivitis:

• Any purulent conjunctivitis in a neonate is an emergency until gonococcal and chlamydial causes are ruled out 5
• May require hospitalization for parenteral therapy 2

Follow-Up Recommendations

For viral conjunctivitis:

• Patients with severe cases should be re-evaluated within 1 week 2
• Those not on corticosteroids should return if symptoms persist beyond 2-3 weeks 2

For bacterial conjunctivitis:

• Re-evaluate if no improvement after 5-7 days of antibiotic therapy 2

For patients on topical corticosteroids:

• Regular monitoring of intraocular pressure required 2
• Periodic pupillary dilation 2

Infection Control Measures

For infectious conjunctivitis:

• Avoid contact lens wear during any form of infectious conjunctivitis 2
• Disinfect surfaces with EPA-registered hospital disinfectant 1, 2
• Dilute bleach soak (1:10 concentration) effective for tonometer disinfection 1
• 70% isopropyl alcohol no longer recommended for tonometer disinfection 1