What is the best treatment for a patient with acute otitis externa (swimmer's ear)?

Best Treatment for Swimmer's Ear (Acute Otitis Externa)

Topical antibiotic ear drops are the definitive first-line treatment for uncomplicated swimmer's ear—oral antibiotics should NOT be used initially. 1, 2

First-Line Treatment: Topical Antimicrobial Drops

The cornerstone of treatment is topical antimicrobial therapy, which achieves clinical cure rates of 65-90% within 7-10 days regardless of which specific FDA-approved agent you choose. 2 These drops deliver drug concentrations 100-1000 times higher than oral antibiotics and provide superior outcomes. 2

Selecting the Right Topical Agent

Your choice depends primarily on tympanic membrane integrity:

• If the eardrum is intact or you're certain there's no perforation: Any FDA-approved topical preparation works equally well. 2 Options include:

  • Ofloxacin 0.3% (non-ototoxic fluoroquinolone) 2
  • Ciprofloxacin 0.2% 3
  • Neomycin/polymyxin B/hydrocortisone 1

• If the eardrum is perforated, you see a tympanostomy tube, or integrity is uncertain: Use ONLY non-ototoxic fluoroquinolone preparations (ofloxacin 0.3% or ciprofloxacin). 1, 2 Never use aminoglycoside-containing drops (like neomycin) in these situations due to ototoxicity risk. 2

Critical Pre-Treatment Step: Clean the Ear Canal

Before administering any drops, you must remove debris, cerumen, and inflammatory material from the ear canal—this ensures medication actually reaches the infected tissue. 1, 2 Use gentle suction, dry mopping, or irrigation with body-temperature water/saline. 2

Important caveat: In diabetic or immunocompromised patients, avoid irrigation entirely (it can trigger necrotizing otitis externa) and use only atraumatic suctioning under microscopic guidance instead. 2, 4

Proper Drop Administration Instructions

Give patients these specific instructions to maximize effectiveness (only 40% self-administer correctly otherwise): 2

• Warm the bottle in your hands for 1-2 minutes to prevent dizziness 1, 2
• Have someone else instill the drops if possible 1, 2
• Lie with affected ear upward and fill the ear canal completely 1, 2
• Stay in this position for 3-5 minutes (use a timer—this is critical for penetration) 1, 2
• Apply gentle to-and-fro movement of the ear or press the tragus in/out to eliminate trapped air 1, 2

Treatment Duration

Prescribe drops for a minimum of 7 days, 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 (14 days total maximum). 1

Pain Management is Essential

Pain from swimmer's ear can be severe and disproportionate to visual findings. 2

• Prescribe appropriate analgesics (acetaminophen or NSAIDs) based on pain severity 1, 2
• Inform patients that pain typically improves within 48-72 hours of starting drops 1, 2
• Do NOT use topical anesthetic drops (benzocaine)—they're not FDA-approved for active infections and can mask treatment failure 1, 2

When to Use Oral Antibiotics (Rarely)

Approximately 20-40% of patients inappropriately receive oral antibiotics, which are often inactive against the causative pathogens (Pseudomonas aeruginosa and Staphylococcus aureus). 2

Reserve systemic antibiotics ONLY for: 1, 2

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

When systemic therapy is needed, use fluoroquinolones (like ciprofloxacin) for Pseudomonas and Staph aureus coverage. 2

Special Populations Requiring Modified Management

Diabetic or Immunocompromised Patients

• Monitor carefully for necrotizing otitis externa 2, 4
• Avoid ear canal irrigation—use only atraumatic suctioning 2, 4
• Consider adding systemic antibiotics even for seemingly uncomplicated cases 2, 4
• Watch for fungal co-infection (otomycosis), which is more common in this population 2

Suspected Fungal Infection

If you see white fuzzy exudate with pruritus or if the patient fails antibacterial therapy, suspect fungal otitis externa. 2 Treat with thorough debridement and topical antifungals 3-4 times daily for 7-10 days. 2 Avoid antibacterial drops that promote fungal overgrowth. 1, 2

When to Place a Wick

If severe canal edema prevents drop entry or you cannot visualize most of the tympanic membrane, place a compressed cellulose wick. 1, 2 The wick expands when exposed to moisture, facilitating drug delivery and reducing edema. 2 It may fall out on its own as inflammation resolves—this is a good sign. 1

Patient Education and Activity Restrictions

• Keep the ear dry during treatment 1, 2
• Cover the ear canal with an earplug or petroleum jelly-coated cotton before showering 1
• Avoid inserting anything into the ear canal, including cotton swabs 1
• Check with you regarding swimming—generally avoid during active infection 1
• If the patient tastes the drops, there's likely a tympanic membrane perforation—notify you immediately 1

When to Reassess

Patients should return if no improvement occurs within 48-72 hours. 1, 2 Consider these causes of treatment failure: 2

• Inadequate drug delivery (canal obstruction)
• Poor adherence to therapy
• Fungal co-infection
• Allergic contact dermatitis (especially from neomycin, which affects 5-15% of patients with chronic otitis externa) 2
• Incorrect diagnosis

Common Pitfalls to Avoid

• Prescribing oral antibiotics for uncomplicated cases (they're inferior to topical therapy) 2
• Using ototoxic preparations when tympanic membrane integrity is compromised 1, 2
• Failing to clean the ear canal before administering drops 1, 2
• Inadequate pain management 1, 2
• Missing fungal infections, especially in diabetics or treatment failures 1, 2
• Using ear candles—they cause harm (perforation, hearing loss, canal obstruction) and have zero efficacy 1