What is the treatment for otitis externa?

Treatment of Otitis Externa

Topical antimicrobial preparations are the treatment of choice for uncomplicated acute otitis externa, with systemic antibiotics reserved only for specific situations. 1

Diagnosis and Assessment

Before initiating treatment, it's important to:

• Confirm diffuse acute otitis externa (AOE) by identifying:

  • Rapid onset of ear canal inflammation
  • Tenderness of tragus, pinna, or both (often disproportionate to visual findings)
  • Ear canal edema and erythema
  • Otorrhea (if present)

• Assess for modifying factors that may alter management:

  • Non-intact tympanic membrane or tympanostomy tubes
  • Diabetes
  • Immunocompromised state
  • Prior radiotherapy
  • Extension of infection beyond the ear canal

First-Line Treatment

1. Topical Antimicrobial Therapy

• Prescribe topical antimicrobial preparations for initial therapy of uncomplicated AOE 1
• Common options include:
  • Fluoroquinolone preparations (e.g., ofloxacin 0.3% otic solution)
  • Aminoglycoside combinations with hydrocortisone
  • Acetic acid preparations

Dosing for Ofloxacin 0.3% Otic Solution 2:

• Children (6 months to 13 years): Five drops once daily for 7 days
• Adolescents and adults (≥13 years): Ten drops once daily for 7 days

2. Pain Management

• Assess pain severity and prescribe appropriate analgesics 1
• Options based on pain severity:
  • Mild to moderate: Acetaminophen or NSAIDs
  • Moderate to severe: NSAIDs plus opioid (limited quantity for 48-72 hours)
• NSAIDs have been shown to significantly reduce pain compared to placebo during acute phase 1

3. Aural Toilet (When Needed)

• If ear canal is obstructed, perform:
  • Gentle cleaning/suctioning to remove debris
  • Consider placing a wick to facilitate medication delivery in severely swollen canals 1

Special Considerations

Non-intact Tympanic Membrane

• Use only non-ototoxic preparations (e.g., fluoroquinolones like ofloxacin) 1, 2
• Ofloxacin is FDA-approved for use with perforated tympanic membranes 2

When to Use Systemic Antibiotics

• Do not use systemic antibiotics as initial therapy for uncomplicated AOE 1
• Reserve systemic antibiotics only for:
  • Extension of infection beyond the ear canal
  • Diabetic patients
  • Immunocompromised patients
  • After radiotherapy
  • When topical therapy cannot reach the infection site 1

Fungal Otitis Externa (Otomycosis)

• Suspect if patient fails to respond to initial antibacterial therapy
• Treatment includes:
  • Debridement
  • Topical antifungal therapy
  • Avoid topical antibiotics as they may promote fungal overgrowth 1

Patient Instructions

1. Medication administration:

   • Warm drops by holding bottle in hand for 1-2 minutes
   • Lie with affected ear upward
   • Instill prescribed number of drops
   • Maintain position for 5 minutes 2

2. Duration of therapy:

   • Continue treatment for full 7 days even if symptoms improve sooner 1
   • Expect improvement within 48-72 hours

3. Water precautions:

   • Cover ear canal with earplug or cotton with petroleum jelly when showering
   • Avoid swimming until infection resolves 1

Follow-up

• If no improvement within 48-72 hours, reassess to:

  • Confirm diagnosis
  • Ensure proper medication delivery
  • Consider alternative diagnoses or resistant organisms
  • Consider culture of ear drainage 1

• Complete resolution typically occurs within 7-10 days with appropriate therapy 3

Clinical Efficacy

Ofloxacin otic solution has demonstrated high clinical cure rates (>90%) in clinical trials, with eradication rates of 96% for common pathogens including Pseudomonas aeruginosa and Staphylococcus aureus 3, 4. Once-daily dosing has shown equivalent efficacy to more frequent administration regimens, potentially improving patient adherence 5.