What is the first‑line treatment for uncomplicated acute otitis externa (swimmer’s ear)?

Treatment of Acute Otitis Externa

Topical antimicrobial ear drops are the definitive first-line treatment for uncomplicated acute otitis externa—oral antibiotics should NOT be prescribed initially. 1, 2, 3

Essential Pre-Treatment Step: Aural Toilet

Before administering any ear drops, the canal must be cleared of debris, cerumen, and inflammatory material to ensure medication reaches infected tissue. 1, 2, 3 This can be accomplished through:

• Gentle suction or dry mopping (preferred method) 2, 3
• Irrigation with body-temperature water, saline, or hydrogen peroxide 2, 3
• Critical exception: In diabetic or immunocompromised patients, use only atraumatic suctioning under microscopic guidance—never irrigate, as this can trigger necrotizing otitis externa 2, 3

If severe canal edema prevents drop entry or the tympanic membrane cannot be visualized, place a compressed cellulose wick to facilitate drug delivery. 2, 3

Topical Antimicrobial Selection

When Tympanic Membrane Integrity is Uncertain or Compromised

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

• Ofloxacin 0.3% otic solution 2, 3
• Ciprofloxacin 0.2% otic solution 2, 3, 4

Never use aminoglycoside-containing drops (e.g., neomycin/polymyxin B) when membrane integrity is uncertain—these are ototoxic. 1, 2, 3

When Tympanic Membrane is Intact

Any FDA-approved topical preparation is acceptable, as all achieve 65-90% clinical cure rates within 7-10 days with no consistent superiority of one agent over another. 2, 3, 5 Options include:

• Fluoroquinolone drops (ofloxacin, ciprofloxacin) 2, 3
• Aminoglycoside/polymyxin B combinations with steroid 1, 2
• Acetic acid 2% (less effective beyond week 1) 2, 5

Topical antimicrobials containing steroids are significantly more effective than placebo (OR 11,95% CI 2.00-60.57). 5 The steroid component hastens pain relief in some trials. 1

Important caveat: Neomycin causes contact sensitivity in 13-30% of patients with chronic otitis externa—avoid in patients with history of contact dermatitis or eczema. 1, 2

Proper Drop Administration Technique

Instruct patients (or have someone else administer): 2, 3, 4

• Warm the bottle in hands for 1-2 minutes to prevent dizziness 2, 4
• Lie with affected ear upward 2, 4
• Fill the ear canal completely with drops 2, 4
• Maintain position for 3-5 minutes (use a timer) 2, 4
• Apply gentle tragal pumping or to-and-fro movement of pinna to eliminate trapped air 2, 3
• Keep ear dry during treatment—use earplug or petroleum jelly-coated cotton when showering 2, 3

Only 40% of patients self-administer drops correctly—having someone else apply them significantly improves adherence. 2, 3

Treatment Duration

Prescribe drops for a minimum of 7 days, even if symptoms resolve earlier. 2, 3, 4 If symptoms persist beyond 7 days, continue drops until resolution for a maximum of 7 additional days (14 days total maximum). 2, 5

Pain Management

Pain assessment and appropriate analgesia are essential—otitis externa pain can be severe. 1, 2, 3

• For mild-to-moderate pain: Acetaminophen or NSAIDs 1, 2, 3
• For severe pain: Short-term opioid-containing analgesics for the initial 48-72 hours 1, 2
• Pain typically improves within 48-72 hours of starting topical therapy 1, 2, 3

Do NOT use topical anesthetic drops (benzocaine)—they are not FDA-approved for active infections and can mask treatment failure. 1, 2

When Systemic Antibiotics ARE Indicated

Oral antibiotics should be reserved ONLY for: 1, 2, 3

• Extension of infection beyond the ear canal (periauricular cellulitis, swelling) 1, 2, 3
• Diabetes mellitus or immunocompromised status 1, 2, 3
• Severe canal edema preventing adequate topical drug delivery 2, 3
• Treatment failure after 48-72 hours of appropriate topical therapy 2, 3

When systemic therapy is indicated, use fluoroquinolones (e.g., ciprofloxacin 500 mg twice daily) to cover Pseudomonas aeruginosa and Staphylococcus aureus, which cause 98% of cases. 2, 3, 6

Evidence strongly supports topical-only therapy: Topical antibiotics achieve 77-96% cure rates versus only 30-67% for oral antibiotics, and deliver drug concentrations 100-1000 times higher at the infection site. 1, 2, 3 Yet 20-40% of patients inappropriately receive oral antibiotics. 2, 3

Reassessment and Treatment Failure

Reassess within 48-72 hours if no improvement occurs. 2, 3 Common causes of treatment failure include: 2, 3

• Inadequate drug delivery due to canal obstruction or poor adherence 2, 3
• Allergic contact dermatitis from topical agents (especially neomycin or hydrocortisone) 1, 2
• Fungal co-infection (otomycosis)—suspect if white fuzzy exudate with pruritus; requires antifungal therapy and debridement 2, 3
• Incorrect diagnosis (e.g., chronic suppurative otitis media, necrotizing otitis externa) 2, 3

Special Populations Requiring Modified Management

Diabetic or Immunocompromised Patients

• Monitor carefully for necrotizing otitis externa—a life-threatening complication 2, 3
• Use only atraumatic suctioning (never irrigate) 2, 3
• Consider adding systemic antibiotics even for seemingly uncomplicated cases 2, 3
• Higher susceptibility to fungal infections 2, 3

Patients with Tympanostomy Tubes or Prior Ear Surgery

• Use only non-ototoxic fluoroquinolones 2, 3, 7

Patients with Eczema or Contact Dermatitis History

• Avoid neomycin-containing preparations entirely 1, 2
• Use fluoroquinolone-only drops 2, 8

Common Pitfalls to Avoid

• Prescribing oral antibiotics for uncomplicated cases 1, 2, 3
• Using ototoxic preparations when tympanic membrane integrity is compromised 1, 2, 3
• Skipping aural toilet before drop administration—medication cannot penetrate debris 2, 3
• Inadequate pain management 1, 2, 3
• Irrigating the ear in diabetic/immunocompromised patients 2, 3
• Missing fungal infections, especially in diabetics or after antibiotic failure 2, 3
• Prescribing neomycin to patients with eczema or chronic otitis externa 1, 2