What is the recommended treatment for otitis externa?

Treatment of Otitis Externa

The recommended first-line treatment for otitis externa is topical fluoroquinolone eardrops, such as ofloxacin 0.3% otic solution, administered once daily for 7 days, even if symptoms improve sooner. 1

Dosing and Administration

• For children (6 months to 13 years): Five drops (0.25 mL) instilled into the affected ear once daily for seven days 2
• For patients 13 years and older: Ten drops (0.5 mL) instilled into the affected ear once daily for seven days 2

Proper Administration Technique

1. Warm the bottle by holding it in hand for 1-2 minutes to prevent dizziness
2. Position patient lying with affected ear upward
3. Instill drops into ear canal
4. Maintain position for 5 minutes to facilitate penetration
5. Repeat for opposite ear if necessary 1, 2

Efficacy and Evidence

Topical fluoroquinolone eardrops have demonstrated clinical cure rates of 77-96% compared to oral antibiotics 1. A multicenter study showed that ofloxacin otic solution administered once daily for 7 days achieved a 91% cure rate overall (95% in children, 88% in adolescents/adults) 3. This regimen is as effective as neomycin/polymyxin B/hydrocortisone preparations but with better tolerability 4.

Adjunctive Measures

• Pain management: Acetaminophen or ibuprofen for pain relief during the first few days of treatment 1
• Ear care during treatment:
  • Keep ears dry
  • Use cotton with petroleum jelly to cover ear canal during showering
  • Avoid swimming until infection resolves
  • Avoid inserting anything into the ear canal (including cotton-tipped swabs) 1
• Aural toilet: Clear inflammatory debris and obstructing cerumen before medication administration using gentle suctioning or dry mop technique 1

Special Considerations

Fungal Otitis Externa

If fungal infection is suspected, consider topical azole antifungals like clotrimazole or miconazole 1

Perforated Tympanic Membrane

• Use non-ototoxic topical preparations
• Fluoroquinolone drops are generally considered safe for middle ear exposure 1

High-Risk Patients

• Diabetic or immunocompromised patients require closer monitoring
• Lower threshold for adding systemic antibiotics due to risk of necrotizing (malignant) otitis externa 1
• Consider ciprofloxacin for malignant external otitis, which has shown a 96.4% clinical cure rate 5

Treatment Duration

Continue eardrops for at least 7 days, even if symptoms improve sooner, to prevent relapse. If symptoms persist beyond 7 days, notify doctor and continue drops until symptoms resolve (maximum additional 7 days) 1.

Common Pitfalls to Avoid

1. Inadequate administration: Failure to properly instill drops can lead to treatment failure
2. Premature discontinuation: Stopping treatment before completing the full 7-day course increases risk of relapse
3. Anesthetic eardrops: Avoid these as they can mask symptoms of delayed response 1
4. Inappropriate use of systemic antibiotics: Reserve for complicated cases or high-risk patients
5. During pregnancy: Avoid aminoglycosides like gentamicin due to potential fetal risk 1

The once-daily dosing regimen of ofloxacin offers better patient adherence compared to more frequent dosing schedules, with studies showing 98% adherence rates 3.