What is the treatment for an external ear infection?

Treatment of External Ear Infection (Otitis Externa)

The first-line treatment for external ear infection (otitis externa) is topical therapy with a fluoroquinolone preparation with corticosteroid, such as ciprofloxacin 0.3%/dexamethasone 0.1%, administered as 3-4 drops twice daily for 7 days. 1

Initial Assessment and Preparation

Before initiating treatment:

• Check for non-intact tympanic membrane or tympanostomy tubes
• Identify if patient has diabetes or is immunocompromised
• Determine if patient has received prior radiotherapy 1

Treatment Algorithm

Step 1: Ear Canal Cleaning

• Perform gentle ear canal cleaning to remove debris that blocks medication delivery
• Methods include:
  • Gentle lavage with body-temperature water/saline
  • Suction
  • Dry mop technique (blotting with cotton-tipped applicator) 2, 1
• Caution: Avoid ear canal lavage in diabetic or immunocompromised patients as it may contribute to malignant otitis externa 1

Step 2: Topical Antimicrobial Therapy

• For intact tympanic membrane:

  • First choice: Fluoroquinolone preparation with corticosteroid (ciprofloxacin 0.3%/dexamethasone 0.1%) 1
  • Alternative: Neomycin/polymyxin B/hydrocortisone preparation 3
  • Acetic acid preparations can also be effective for mild cases 4

• For perforated tympanic membrane or tympanostomy tubes:

  • Use only non-ototoxic preparations (fluoroquinolones)
  • Avoid aminoglycoside-containing products (neomycin/polymyxin B) 1

Step 3: Proper Drop Administration

1. Lie down with affected ear up
2. Fill ear canal with prescribed drops
3. Remain in position for 3-5 minutes
4. Use gentle to-and-fro movement of pinna or tragal pumping to help drops penetrate
5. Wipe off excess drops
6. Keep ear dry during treatment 2, 1

Step 4: Pain Management

• Assess pain severity and treat accordingly:
  • Mild to moderate pain: Acetaminophen or NSAIDs
  • Severe pain: Consider short-term opioids (48-72 hours) 1

Special Considerations

Treatment Failure

If no improvement after 48-72 hours:

1. Reassess adherence to therapy
2. Consider fungal infection (otomycosis)
3. Consider alternative topical therapy
4. Obtain culture of ear canal discharge 2, 1

Systemic Antibiotics

Only indicated when:

• Infection extends beyond the ear canal
• Patient has diabetes or is immunocompromised
• Concurrent acute otitis media requires systemic treatment

If needed, choose antibiotics active against both Pseudomonas aeruginosa and Staphylococcus aureus 1

Prevention of Recurrence

• Keep ears dry
• Use ear protection when showering or washing hair
• Consider acidifying ear drops after swimming if recurrent episodes occur
• Avoid inserting foreign objects into the ear canal 1

Efficacy of Treatment Options

Topical treatments are highly effective with cure rates of:

• Fluoroquinolone preparations: 91-96% 5, 6
• Neomycin/polymyxin B combinations: 94-97% 6, 7

The neomycin/polymyxin B combination shows synergistic effects against common pathogens, particularly P. aeruginosa 7, but fluoroquinolone preparations avoid the risk of ototoxicity associated with neomycin 6.

Common Pitfalls to Avoid

1. Failing to clean the ear canal before administering drops
2. Using ototoxic preparations in patients with perforated tympanic membranes
3. Inadequate pain management
4. Unnecessary use of systemic antibiotics
5. Improper drop administration technique
6. Self-cleaning by patients, which can damage the ear canal 2, 1