What is the treatment for red eyes?

Treatment of Red Eyes

The treatment of red eyes depends entirely on the underlying cause, which must be identified through immediate assessment for red flags followed by etiology-specific therapy—viral conjunctivitis requires only supportive care with preservative-free artificial tears, bacterial conjunctivitis needs broad-spectrum topical antibiotics for moderate-to-severe cases, and allergic conjunctivitis responds to dual-action topical antihistamine/mast cell stabilizers. 1

Immediate Assessment for Red Flags Requiring Urgent Referral

Before initiating any treatment, you must screen for critical red flags that mandate same-day ophthalmology referral or emergency department evaluation 1:

• Visual loss or decreased visual acuity 1
• Moderate to severe ocular pain 1
• Corneal involvement (loss of transparency, opacity, or infiltrate) 1
• Severe purulent discharge 1
• History of herpes simplex virus eye disease 1
• Immunocompromised state 1
• Unilateral red eye with pain 1

Any single one of these features requires urgent ophthalmology consultation within 24 hours. 1

Etiology-Specific Treatment Algorithm

Viral Conjunctivitis

Do not prescribe antibiotics—they provide no benefit and may cause harm. 1, 2

• Supportive care only: Preservative-free artificial tears 4 times daily 1
• Cold compresses for symptomatic relief 1
• Patient education: Highly contagious for 10-14 days from symptom onset; avoid touching eyes, wash hands frequently, use disposable towels, avoid sharing personal items 2
• Natural course: Self-limited, typically resolves within 5-14 days 2

Critical pitfall: Topical corticosteroids should be avoided in routine viral conjunctivitis, as they prolong viral shedding and can worsen HSV infections. 2 They may only be considered in severe cases with marked chemosis, lid swelling, or subepithelial infiltrates causing vision impairment, but require close ophthalmology follow-up with regular IOP monitoring. 3, 1

Bacterial Conjunctivitis

• Mild cases: Usually self-limited and may resolve without treatment 2
• Moderate to severe cases: 5-7 day course of broad-spectrum topical antibiotic 1, 2
  • No specific agent has proven superiority—choose based on convenience and cost 2
  • Options include polymyxin B/trimethoprim 4 or erythromycin ointment 5
  • Dosing: Apply to affected eye(s) 4-6 times daily depending on severity 5

Special considerations:

• Gonococcal conjunctivitis: Requires systemic treatment in addition to topical therapy due to risk of corneal perforation; hospitalization for parenteral therapy 1, 2
• Chlamydial conjunctivitis: Requires systemic treatment and evaluation/treatment of sexual partners 1, 2

Allergic Conjunctivitis

First-line therapy:

• Dual-action topical agents (antihistamine + mast cell stabilizer) such as olopatadine or ketotifen, 1 drop twice daily 1, 6
• Environmental modifications: Wear sunglasses as barrier to airborne allergens, use cold compresses, refrigerated preservative-free artificial tears 4 times daily 6
• Avoid eye rubbing (can worsen symptoms and lead to keratoconus) 6

Second-line therapy for refractory cases:

• Short course (1-2 weeks) of low-potency topical corticosteroid such as loteprednol etabonate 1, 6
• Requires baseline and periodic IOP monitoring and pupillary dilation to evaluate for glaucoma and cataracts 1, 6

Critical pitfall: Avoid chronic use of topical vasoconstrictors (>10 days), which can cause rebound hyperemia. 6 Oral antihistamines are less effective than topical agents and can worsen dry eye. 6

Herpes Simplex Virus Conjunctivitis

Requires immediate ophthalmology referral. 1, 2 If treatment is initiated:

• Topical antiviral: Ganciclovir 0.15% gel 3-5 times daily 3
• Oral antiviral: Acyclovir 200-400 mg five times daily, valacyclovir 500 mg 2-3 times daily, or famciclovir 250 mg twice daily 3
• Avoid topical corticosteroids—they potentiate HSV epithelial infections 3
• Follow-up within 1 week with visual acuity measurement and slit-lamp biomicroscopy 3

Follow-Up Recommendations

• Patients without red flags and not on corticosteroids: Return if symptoms persist beyond 2-3 weeks 3
• Patients on topical corticosteroids: Regular monitoring of IOP and periodic pupillary dilation 3, 1
• Lack of response to therapy after 3-4 days: Refer to ophthalmology 1
• Recurrent episodes or conjunctival scarring: Refer to ophthalmology 1

Common Pitfalls to Avoid

• Never use topical corticosteroids indiscriminately—they can prolong adenoviral infections, worsen HSV infections, and cause elevated IOP and cataracts 2
• Avoid contact lens wear during any infectious conjunctivitis 2
• Do not prescribe topical antibiotics for viral conjunctivitis—they cause unnecessary toxicity without benefit 1, 2
• Do not miss gonococcal conjunctivitis—it can cause corneal perforation and requires immediate systemic treatment 2