What is the recommended treatment for otitis externa?

Treatment of Otitis Externa

Topical antimicrobial therapy is the definitive first-line treatment for uncomplicated acute otitis externa, NOT oral antibiotics, with clinical cure rates of 65-90% within 7-10 days. 1

Initial Management Steps

Before prescribing any medication, perform aural toilet to remove debris, cerumen, and inflammatory material from the ear canal—this is essential because medication cannot reach infected tissues if the canal is obstructed. 1, 2 Use gentle suction, dry mopping, or irrigation with body-temperature water, saline, or hydrogen peroxide. 1

Critical caveat: In diabetic or immunocompromised patients, avoid aggressive irrigation as this can trigger necrotizing otitis externa—use atraumatic suctioning under microscopic guidance instead. 1

If severe canal edema prevents drop entry or you cannot visualize most of the tympanic membrane, place a compressed cellulose wick that expands when exposed to moisture, facilitating drug delivery. 1

Topical Antimicrobial Selection

Your choice depends on tympanic membrane integrity:

For Intact Tympanic Membrane (or Confirmed Intact)

Any FDA-approved topical preparation is acceptable, including: 1

• Neomycin/polymyxin B/hydrocortisone (most cost-effective)
• Ofloxacin 0.3%
• Ciprofloxacin 0.2%

However, avoid neomycin-containing preparations if the patient has any history of contact dermatitis—neomycin causes allergic reactions in 5-15% of patients with chronic external otitis. 1

For Perforated Tympanic Membrane, Tympanostomy Tubes, or Uncertain Integrity

Use ONLY non-ototoxic fluoroquinolone preparations: 1, 2, 3, 4

• Ofloxacin 0.3%: 5 drops once daily for 7 days (ages 6 months-12 years) or 10 drops once daily for 7 days (≥13 years) 3
• Ciprofloxacin 0.2%: 0.25 mL (one single-dose container) twice daily for 7 days 4

Never use aminoglycoside-containing drops (neomycin, gentamicin) when tympanic membrane integrity is compromised due to ototoxicity risk. 1, 2

Why Topical Therapy Works Better

Topical antibiotics deliver concentrations 100-1000 times higher than systemic therapy at the infection site and provide superior coverage against Pseudomonas aeruginosa (the causative pathogen in 20-60% of cases) and Staphylococcus aureus (10-70% of cases). 1, 5 Randomized trials show topical therapy achieves clinical cure rates of 77-96% versus only 30-67% for oral antibiotics. 1

Proper Drop Administration (Critical for Success)

Only 40% of patients self-administer drops correctly—improper technique is a major cause of treatment failure. 1 Instruct patients to:

1. Warm the bottle in hands for 1-2 minutes to prevent dizziness 3, 4
2. Lie with affected ear upward 1, 3
3. Fill the ear canal completely with drops 1
4. Maintain position for 3-5 minutes (not just seconds) 1, 3
5. Apply gentle to-and-fro movement of pinna or tragal pumping to eliminate trapped air 1
6. Have someone else administer drops if possible—this significantly improves adherence 1

Pain Management

Pain assessment and appropriate analgesics are essential—otitis externa pain can be severe due to the highly sensitive periosteum of underlying bone. 1, 5

• Mild-to-moderate pain: Acetaminophen or NSAIDs 1, 5
• Severe pain: Consider short-term opioid-containing analgesics for the initial 48-72 hours 1, 5
• Expected timeline: Pain typically improves within 48-72 hours of starting appropriate topical therapy 1, 2

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

When to Use Systemic Antibiotics

Oral antibiotics should NOT be used as initial therapy for uncomplicated otitis externa. 1, 2, 5 Approximately 20-40% of patients inappropriately receive oral antibiotics, and most prescribed oral antibiotics are inactive against P. aeruginosa. 1

Reserve systemic antibiotics ONLY for: 1, 2, 5

• Extension of infection beyond the ear canal (periauricular swelling/cellulitis)
• Diabetes mellitus or immunocompromised status
• Topical therapy cannot reach infected area (complete canal obstruction)
• Treatment failure after 48-72 hours of appropriate topical therapy

When systemic antibiotics are indicated, use fluoroquinolones (ciprofloxacin 500-750 mg PO twice daily) for coverage against Pseudomonas aeruginosa and Staphylococcus aureus. 1

Special Populations Requiring Modified Management

Diabetic or Immunocompromised Patients

• Monitor carefully for necrotizing otitis externa—can present initially with symptoms similar to uncomplicated otitis externa 1
• Consider adding systemic antibiotics even for uncomplicated cases 1, 2
• Higher susceptibility to fungal infections (otomycosis) 1
• Use atraumatic suctioning, not irrigation 1

Fungal Otitis Externa (Otomycosis)

Suspect if: 1

• White fuzzy exudate with pruritus and discharge
• Treatment failure with antibacterial drops
• Patient with diabetes or recent antibiotic use

Treatment: Thorough but gentle debridement of fungal debris + topical antifungal preparations 3-4 times daily for 7-10 days. Avoid antibacterial drops that promote fungal overgrowth. 1

Treatment Failure: Reassessment at 48-72 Hours

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

• Inadequate drug delivery due to persistent canal obstruction—repeat aural toilet
• Poor adherence to therapy—review administration technique
• Allergic contact dermatitis from topical agents (especially neomycin or hydrocortisone)—switch to fluoroquinolone alone
• Fungal co-infection—add antifungal therapy
• Incorrect diagnosis—consider chronic otitis externa from underlying dermatitis

Patient Education and Activity Restrictions

• Keep ear dry during treatment—cover canal with petroleum jelly-coated cotton or earplug before showering 1, 2
• Complete full 7-day course even if symptoms resolve early 1, 2
• If you taste the eardrops, notify your doctor immediately—this indicates tympanic membrane perforation 1
• Return for reassessment if no improvement within 48-72 hours 1
• NEVER use ear candles—they have no proven efficacy and can cause harm including canal obstruction, hearing loss, and tympanic membrane perforation 1, 2

Common Pitfalls to Avoid

• Prescribing oral antibiotics for uncomplicated cases 1, 2
• Using ototoxic aminoglycoside preparations when tympanic membrane integrity is unknown or compromised 1, 2
• Failing to perform aural toilet before administering drops 1, 2
• Inadequate pain management 1, 2
• Missing fungal infections, especially in diabetic patients or those failing antibacterial therapy 1, 2
• Prescribing neomycin-containing drops to patients with history of contact dermatitis 1