What are the recommended oral antibiotics (abx) for eye infections?

Oral Antibiotics for Eye Infections

For most eye infections, oral antibiotics are NOT first-line therapy—topical antibiotics are preferred for bacterial conjunctivitis and corneal infections. 1, 2 However, oral antibiotics are specifically indicated for chlamydial conjunctivitis, gonococcal conjunctivitis, and certain systemic infections affecting the eye.

When Oral Antibiotics ARE Indicated

Chlamydial Conjunctivitis (Inclusion Conjunctivitis/Trachoma)

Oral azithromycin or doxycycline is the standard treatment for chlamydial eye infections. 1, 3

• First-line option: Oral azithromycin as a single dose 1
• Alternative: Doxycycline 100 mg orally twice daily for 7 days in adults and children ≥8 years 3
• For pregnant women: Use erythromycin or amoxicillin instead of doxycycline 3
• For children <8 years: Use erythromycin or azithromycin instead of doxycycline 3

Critical pitfall: Sexual partners must be treated to prevent reinfection, and patients should be retested approximately 3 months after treatment 3

Gonococcal Conjunctivitis

Systemic antibiotic therapy with ceftriaxone is the first-choice treatment. 1

• First-line: Ceftriaxone (systemic) 1
• Alternative if ceftriaxone unavailable: Doxycycline 100 mg orally twice daily for 7 days 3
• Adjunctive therapy: Add saline lavage to promote comfort and faster resolution 1
• If co-infection suspected: Treat both gonorrhea and chlamydia appropriately 3

Critical pitfall: Obtain conjunctival cultures and Gram staining before initiating treatment for moderate to severe infections, especially if gonococcal infection is suspected 1

When Topical Antibiotics Are Preferred (NOT Oral)

Standard Bacterial Conjunctivitis

Topical antibiotics like azithromycin are first-line treatment, NOT oral antibiotics. 1

• Recommended: 5-7 day course of broad-spectrum topical antibiotic 1
• Specific agent: Topical azithromycin accelerates clinical and microbiological remission 1
• Alternatives: Topical gentamicin, tetracycline, or ofloxacin 1

Bacterial Keratitis

Topical fluoroquinolones are recommended, with systemic antibiotics considered only for lesions close to the limbus. 1

Periocular Infections Requiring Oral Antibiotics

Preseptal Cellulitis

Oral antibiotics can be used for preseptal cellulitis in adults and older children if the orbit and optic nerve are not involved and the patient is otherwise healthy. 4

Critical pitfall: Orbital or optic nerve involvement demands orbital imaging and more aggressive intervention—oral antibiotics alone are insufficient 4

Algorithmic Approach to Oral Antibiotics for Eye Infections

1. Identify the infection type:

   • Chlamydial conjunctivitis → Oral azithromycin (single dose) OR doxycycline 100 mg twice daily × 7 days 1, 3
   • Gonococcal conjunctivitis → Systemic ceftriaxone (first choice) OR doxycycline 100 mg twice daily × 7 days (alternative) 1, 3
   • Standard bacterial conjunctivitis → Topical antibiotics (NOT oral) 1
   • Preseptal cellulitis (no orbital involvement) → Oral antibiotics acceptable 4

2. Check for contraindications:

   • Pregnant? → Avoid doxycycline; use erythromycin or amoxicillin 3
   • Child <8 years? → Avoid doxycycline; use erythromycin or azithromycin 3

3. Ensure appropriate follow-up:

   • Chlamydial infections → Treat sexual partners and retest at 3 months 3
   • Severe infections → Obtain cultures before treatment 1