Recommended Dosages and Treatment Durations for Bacterial Conjunctivitis

For children over 12 months and adults with uncomplicated bacterial conjunctivitis, use topical fluoroquinolones (moxifloxacin, levofloxacin, gatifloxacin, ciprofloxacin, or besifloxacin) administered four times daily for 5–7 days. 1

First-line therapy:

Apply topical fluoroquinolone (moxifloxacin 0.5%, levofloxacin, gatifloxacin, ciprofloxacin, or besifloxacin 0.6%) four times daily for 5–7 days. 1, 2
All fluoroquinolones listed are FDA-approved for children older than 12 months and provide effective coverage against Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae. 1
No single fluoroquinolone demonstrates superiority over others, so selection can be based on dosing convenience (moxifloxacin three times daily may improve adherence), cost, and local resistance patterns. 1
Fourth-generation fluoroquinolones (moxifloxacin, besifloxacin) offer superior gram-positive coverage, including activity against some MRSA strains. 1

Expected outcomes:

Topical antibiotics provide earlier clinical and microbiological remission (68% cure rate versus 55% with placebo by days 4–9), allowing faster return to school or work. 1
Complete resolution occurs in 81% of patients by 48 hours with moxifloxacin. 3
Approximately 64% of mild cases resolve spontaneously by days 6–10 without treatment, but antibiotics shorten symptom duration and reduce transmissibility. 1

Reserve fluoroquinolones for enhanced Pseudomonas coverage:

Use ofloxacin 0.3% or ciprofloxacin 0.3% four times daily for 5–7 days due to higher risk of Pseudomonas aeruginosa infection in contact-lens wearers. 1
Discontinue contact lens use during treatment and until complete resolution. 1

Immediate ophthalmology referral and systemic treatment are mandatory:

For gonococcal conjunctivitis (onset 1–7 days after birth):

Administer ceftriaxone 25–50 mg/kg IV or IM single dose (maximum 125 mg) PLUS topical antibiotics and saline lavage. 1, 2
Daily ophthalmology follow-up is required until complete resolution to prevent corneal perforation, which can occur within 24 hours. 1
Obtain conjunctival cultures and Gram stain before initiating therapy. 1
Evaluate and treat the mother and sexual partners; consider sexual abuse. 1

For chlamydial conjunctivitis (onset 5–12 days after birth):

Administer erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses for 14 days. 1, 2
Systemic therapy is mandatory because more than 50% of affected infants have concurrent nasopharyngeal, genital, or pulmonary infection. 1
Topical antibiotics provide no additional benefit beyond systemic therapy. 1
Monitor for infantile hypertrophic pyloric stenosis in infants younger than 6 weeks receiving erythromycin. 1
Re-evaluate after completing the 14-day course; approximately 80% achieve clinical cure, but a second course may be needed if eradication is not confirmed. 1

Second-line topical options:

Use topical gentamicin, tetracycline, or ofloxacin 0.3% four times daily for 5–7 days if fluoroquinolones are unavailable. 1
Povidone-iodine 1.25% ophthalmic solution may be as effective as topical antibiotics in settings with limited antibiotic access. 1, 2

For mild disease in resource-limited settings:

Supportive care alone (cold compresses, refrigerated preservative-free artificial tears four times daily) is appropriate, as mild bacterial conjunctivitis is self-limited in immunocompetent patients. 1

When standard fluoroquinolones fail:

Consider MRSA in patients from nursing homes, those with community-acquired infections, or those failing to respond within 48–72 hours. 1
Obtain conjunctival cultures before switching therapy. 1
Compounded topical vancomycin may be required, as MRSA isolates are generally resistant to fluoroquinolones and aminoglycosides but remain susceptible to vancomycin. 1, 2
Regional resistance data show that 42% of MRSA isolates exhibit concurrent fluoroquinolone resistance. 1

Instruct patients to return in 3–4 days if no improvement is observed. 1, 2

Immediate ophthalmology referral is required for:

Never use combination antibiotic-steroid drops (e.g., Tobradex) in pediatric conjunctivitis unless viral etiology—particularly HSV or adenovirus—has been definitively excluded, as steroids exacerbate viral infections and prolong viral shedding. 1
Oral antibiotics (e.g., Augmentin) are NOT indicated for routine bacterial conjunctivitis, as they cannot achieve therapeutic levels in the conjunctiva and are reserved exclusively for gonococcal and chlamydial infections. 1
Do not use topical antibiotics for viral conjunctivitis, as they provide no benefit and risk adverse effects and antimicrobial resistance. 1
In neonates, always consider sexual abuse when gonococcal or chlamydial conjunctivitis is diagnosed, and document with standard culture techniques. 1