What is the treatment for an external ear infection?

Treatment of External Ear Infection (Acute Otitis Externa)

Topical antimicrobial therapy is the definitive first-line treatment for uncomplicated acute otitis externa—oral antibiotics should NOT be used initially. 1, 2, 3

Initial Management Steps

Before prescribing any drops, the ear canal must be cleared of debris, cerumen, and inflammatory material through gentle suction, dry mopping, or irrigation to ensure medication reaches infected tissues. 4, 1, 3 This step is critical—failure to remove debris is a common cause of treatment failure. 1

For patients with intact tympanic membranes, any FDA-approved topical preparation is acceptable, with choice based on cost, dosing frequency, and prior allergic reactions. 1 All topical agents achieve 65-90% clinical cure rates within 7-10 days regardless of specific drug. 1, 3

For patients with perforated tympanic membranes or tympanostomy tubes, use ONLY non-ototoxic fluoroquinolone preparations such as ofloxacin 0.3% or ciprofloxacin 0.2%. 1, 3, 5 Never use aminoglycoside-containing drops (like neomycin) in these patients due to ototoxicity risk. 1, 3

Recommended Topical Antibiotics

First-Line Options:

• Ofloxacin 0.3%: 5 drops once daily for children (6 months to <13 years), 10 drops once daily for adolescents/adults, for 7 days 6, 7
• Ciprofloxacin 0.2%: 0.25 mL (contents of one single-dose container) twice daily for 7 days 5
• Neomycin/polymyxin B/hydrocortisone: 3-4 drops 3-4 times daily for 7-10 days (only if tympanic membrane is intact) 4, 7

The fluoroquinolones (ofloxacin, ciprofloxacin) provide excellent coverage against Pseudomonas aeruginosa (20-60% of cases) and Staphylococcus aureus (10-70% of cases), which cause 98% of bacterial otitis externa. 4, 2, 3

Proper Drop Administration Technique

Instruct patients to: 1, 3

• Warm the bottle in hands for 1-2 minutes to prevent dizziness
• Lie with affected ear upward
• Fill the ear canal with drops
• Maintain position for 3-5 minutes (minimum 1 minute for ciprofloxacin) 5
• Apply gentle to-and-fro movement of pinna or tragal pumping to eliminate trapped air 1
• Have someone else administer drops if possible—only 40% of patients self-administer correctly 1

Pain Management

Pain assessment and appropriate analgesic therapy is essential—otitis externa pain can be severe and disproportionate to visual findings. 4, 1, 3

• Mild-to-moderate pain: Acetaminophen or NSAIDs 1, 3
• Severe pain: Consider short-term opioid-containing analgesics for initial 48-72 hours 3
• Pain typically improves within 48-72 hours of starting topical therapy 1, 2, 3

Avoid topical anesthetic drops (benzocaine)—they are not FDA-approved for active infections and can mask delayed treatment response. 1

When to Use Systemic Antibiotics

Reserve oral antibiotics for specific circumstances ONLY: 1, 2, 3

• Extension of infection beyond the ear canal (periauricular cellulitis)
• Diabetes mellitus or immunocompromised status
• Topical therapy cannot reach infected area (severe canal edema despite wick placement)
• Treatment failure after 48-72 hours

When systemic antibiotics are indicated, use fluoroquinolones (ciprofloxacin 750 mg twice daily) for coverage against P. aeruginosa and S. aureus. 1, 8 Most oral antibiotics prescribed for otitis externa are inactive against P. aeruginosa, making them ineffective. 1

Special Populations Requiring Modified Management

Diabetic or Immunocompromised Patients:

• Monitor carefully for necrotizing otitis externa 1, 2, 3
• Avoid aggressive irrigation—use atraumatic suctioning under microscopic guidance instead 1
• Consider adding systemic antibiotics even for uncomplicated cases 1
• Higher risk for fungal infections (otomycosis) 1, 2

Patients with Severe Canal Edema:

Place a compressed cellulose wick if severe edema prevents drop entry or if most of the tympanic membrane cannot be visualized—the wick expands when exposed to moisture, facilitating drug delivery. 1

Treatment Failure: Reassessment at 48-72 Hours

If no improvement occurs within 48-72 hours, consider: 1, 2, 3

• Inadequate drug delivery due to canal obstruction—repeat aural toilet
• Poor adherence to therapy—review administration technique
• Fungal co-infection (otomycosis)—suspect if white fuzzy exudate with pruritus; treat with topical antifungals and debridement 1
• Allergic contact dermatitis from topical agents—neomycin causes reactions in 5-15% of patients with chronic otitis externa 1
• Incorrect diagnosis—consider other conditions

Prevention Strategies

To reduce recurrence: 2, 3

• Remove obstructing cerumen
• Use acidifying ear drops (2% acetic acid) before/after swimming 9
• Dry ear canal with hair dryer on low setting
• Use ear plugs while swimming
• Avoid inserting cotton swabs or other objects into ear canal 1

Common Pitfalls to Avoid

• Overuse of oral antibiotics for uncomplicated cases—approximately 20-40% of patients inappropriately receive oral antibiotics 1
• Using ototoxic preparations (aminoglycosides) when tympanic membrane integrity is compromised 1, 2
• Inadequate pain management—pain can be severe and requires appropriate analgesics 1, 2
• Failure to remove debris before administering drops—prevents medication from reaching infected tissues 1, 2
• Missing fungal infections—especially in diabetic patients or those failing antibacterial therapy 1, 2
• Prescribing antibiotics with inadequate Pseudomonas coverage 1

Expected Clinical Course

Complete the full 7-day course even if symptoms resolve earlier to prevent relapse. 1 If symptoms persist beyond 7 days, continue drops until resolution for a maximum of 7 additional days (total 14 days maximum). 1 Clinical cure rates with appropriate topical therapy are 65-90% within 7-10 days. 1, 3