What is the treatment for a red eye without discharge?

Treatment of Red Eye Without Discharge

For a red eye without discharge, first rule out vision-threatening emergencies through targeted assessment, then treat based on the most likely etiology—typically viral conjunctivitis (supportive care only), allergic conjunctivitis (topical antihistamine/mast cell stabilizers), or non-infectious causes like dry eye or blepharitis (treat the underlying condition). 1

Immediate Red Flag Assessment

Before initiating any treatment, you must identify features requiring urgent ophthalmology referral within 24 hours: 1

• Visual loss or decreased visual acuity 1
• Moderate to severe ocular pain (not relieved by topical anesthetics) 1, 2
• Corneal opacity or loss of corneal transparency 1
• Photophobia 1, 3
• History of herpes simplex virus eye disease 1
• Immunocompromised status 1
• Unilateral presentation with pain (suggests corneal pathology, anterior uveitis, acute angle-closure glaucoma, or HSV) 1

If any of these are present, do not treat empirically—refer immediately. 1, 2

Diagnostic Approach for Red Eye Without Discharge

The absence of discharge narrows your differential significantly and makes bacterial conjunctivitis less likely: 4, 5

Key Historical Features to Elicit:

• Unilateral vs bilateral presentation (unilateral suggests non-conjunctival pathology) 1
• Itching as predominant symptom (strongly suggests allergic etiology) 5, 6
• Recent upper respiratory infection (suggests viral conjunctivitis) 5
• Contact lens wear (raises concern for keratitis) 4
• Environmental/seasonal triggers (suggests allergic conjunctivitis) 4, 6
• Associated symptoms: photophobia, pain, vision changes 1, 3

Physical Examination Findings:

• Follicular reaction on inferior tarsal conjunctiva (viral conjunctivitis) 5
• Papillary reaction (allergic conjunctivitis) 5, 6
• Preauricular lymphadenopathy (viral > bacterial) 5
• Subconjunctival hemorrhage (viral conjunctivitis or trauma) 5
• Corneal clarity (must be preserved; opacity requires referral) 1

Treatment Algorithm by Etiology

1. Viral Conjunctivitis (Most Common with No Discharge)

Viral conjunctivitis requires supportive care only—antibiotics provide no benefit and should be avoided. 4, 1, 5

Treatment: 1, 5

• Preservative-free artificial tears 4 times daily 1, 5
• Cold compresses for symptomatic relief 4, 6
• Topical antihistamines (e.g., ketotifen) for symptomatic relief if itching present 5
• Patient education: highly contagious for 10-14 days; frequent handwashing, avoid sharing towels, avoid close contact 5

Critical pitfall: Do not prescribe topical antibiotics—they cause unnecessary toxicity and do not shorten disease course. 4, 1, 5 Viral conjunctivitis is self-limited, resolving in 5-14 days. 5

When to consider topical corticosteroids: Only in severe cases with pseudomembranes or subepithelial infiltrates affecting vision, and only with close ophthalmology follow-up for IOP monitoring. 5 Corticosteroids can prolong viral shedding and worsen HSV infections. 4, 5

2. Allergic Conjunctivitis (If Itching Predominates)

Itching is the hallmark distinguishing feature of allergic conjunctivitis. 5, 6

First-line treatment: 6

• Dual-action topical agents (antihistamine + mast cell stabilizer): olopatadine, ketotifen, epinastine, or azelastine 6, 7
  • Ketotifen dosing: 1 drop in affected eye(s) twice daily, every 8-12 hours 7
• Environmental modifications: sunglasses as allergen barrier, cold compresses, refrigerated preservative-free artificial tears 4x/day 4, 6
• Avoid eye rubbing (can lead to keratoconus in atopic patients) 6
• Allergen avoidance: hypoallergenic bedding, eyelid cleansers, frequent clothes washing, shower before bed 4, 6

Second-line (if inadequate response in 48-72 hours): 6

• Short course (1-2 weeks) of low-potency topical corticosteroid (loteprednol etabonate) 4, 6
• Baseline and periodic IOP monitoring plus pupillary dilation to evaluate for glaucoma/cataract 4, 6

Critical pitfall: Avoid chronic vasoconstrictor use (>10 days)—causes rebound hyperemia. 6 Avoid oral antihistamines as primary therapy—they worsen dry eye. 6

3. Non-Infectious Causes (Dry Eye, Blepharitis, Irritation)

Red eye without discharge may represent underlying dry eye or blepharitis rather than conjunctivitis. 4

Treatment directed at underlying condition: 4

• Dry eye: preservative-free artificial tears, warm compresses, lid hygiene, treat meibomian gland dysfunction 4
• Blepharitis: lid scrubs, warm compresses, topical antibiotics if indicated 4
• Medication/preservative-induced: discontinue offending agent, use preservative-free formulations 4

4. Subconjunctival Hemorrhage

Benign, self-limited condition requiring reassurance only. 2, 8

• No treatment necessary; resolves spontaneously in 1-2 weeks 2, 8
• Rule out trauma, bleeding disorders, or severe hypertension if recurrent 8

When to Refer to Ophthalmology

Refer if: 1, 5

• Lack of response to therapy after 3-4 days 1
• Recurrent episodes 1
• Conjunctival scarring 1
• Corneal involvement 1
• Any red flag features (pain, vision loss, photophobia, corneal opacity) 1

Follow-Up Strategy

• Viral conjunctivitis: Re-evaluate in 1 week if severe; return if symptoms persist >2-3 weeks 5
• Allergic conjunctivitis: Reassess in 48-72 hours to confirm symptom improvement 6
• Patients on topical corticosteroids: Regular IOP monitoring and pupillary dilation 4, 6

Common Pitfalls to Avoid

• Do not prescribe antibiotics for viral conjunctivitis—no benefit, potential harm 4, 1, 5
• Do not use topical corticosteroids indiscriminately—can prolong adenoviral infections, worsen HSV, cause glaucoma/cataracts 4, 5
• Do not miss unilateral red eye with pain—this is not simple conjunctivitis and requires urgent evaluation 1
• Do not overlook chronic/recalcitrant cases—may indicate underlying malignancy (sebaceous or squamous cell carcinoma) 4, 5