What is the recommended treatment for otitis externa?

Treatment of Otitis Externa

Topical antibiotic preparations should be used as first-line therapy for diffuse, uncomplicated otitis externa rather than systemic antibiotics. 1, 2

Initial Assessment and Diagnosis

• Confirm diagnosis by looking for:

  • Ear canal tenderness
  • Diffuse ear canal edema and erythema
  • With or without otorrhea
  • Assess for modifying factors that alter management:
    • Non-intact tympanic membrane
    • Tympanostomy tubes
    • Diabetes
    • Immunocompromised state
    • Prior radiotherapy

• Pain assessment is essential:

  • Mild to moderate pain: acetaminophen or NSAIDs
  • Severe pain: short-term opioid analgesics may be considered 1, 2

First-Line Treatment

Topical Therapy

1. Fluoroquinolone drops (preferred option):

   • Ofloxacin 0.3% otic solution:
     • Children (6 months-13 years): 5 drops once daily for 7 days
     • Adults (≥13 years): 10 drops once daily for 7 days 3, 4
   • Ciprofloxacin 0.2% otic solution:
     • 0.25 mL (one single-dose container) twice daily for 7 days 5

2. Proper administration technique:

   • Warm solution by holding bottle in hand for 1-2 minutes
   • Patient should lie with affected ear upward
   • Instill drops and maintain position for 5 minutes
   • For non-intact tympanic membranes, pump tragus 4 times 3, 5

3. Aural toilet before medication administration:

   • Clear inflammatory debris and obstructing cerumen
   • Use gentle suctioning or dry mop technique
   • Avoid irrigation in patients with tympanostomy tubes 2

Special Considerations

Non-intact Tympanic Membrane

• Use only non-ototoxic preparations (fluoroquinolones)
• Avoid aminoglycoside-containing products due to risk of ototoxicity 1, 2

Fungal Otitis Externa

• Consider if not responding to antibacterial treatment
• Treat with azole antifungals (clotrimazole or miconazole)
• Apply twice daily for 7-14 days 2

When to Consider Systemic Antibiotics

Systemic antibiotics should only be used when:

• Infection extends beyond the ear canal
• Patient has diabetes mellitus
• Patient is immunocompromised
• Patient has history of radiotherapy
• Fluoroquinolones (ciprofloxacin) are first choice for oral therapy 1, 2

Follow-up and Monitoring

• Reassess within 48-72 hours if no improvement
• Consider fungal etiology if not responding to antibacterial treatment
• Monitor high-risk patients for necrotizing (malignant) otitis externa, particularly in diabetic or immunocompromised patients 2

Prevention of Recurrence

• Keep ears dry
• Use ear protection when showering or washing hair
• Avoid ear canal cleaning with cotton-tip applicators
• For patients with tympanostomy tubes, prevent water entry during periods of active otorrhea 2

Treatment Efficacy

Clinical studies demonstrate high efficacy rates for topical treatments:

• Ofloxacin otic solution: 91% cure rate (95% in children, 88% in adults) 4
• Ciprofloxacin otic solution: 70% cure rate after 7 days of treatment 5
• Topical antibiotics show superior clinical cure rates (77-96%) compared to systemic antibiotics (30-67%) 2

Once-daily ofloxacin otic solution is as effective as neomycin/polymyxin B/hydrocortisone administered four times daily, with the advantage of better compliance due to less frequent dosing 6, 7.