What is the appropriate prescription for a 21‑year‑old with acute otitis externa and no drug allergies?

Treatment of Acute Otitis Externa in a 21-Year-Old

Prescribe a topical fluoroquinolone ear drop—specifically ciprofloxacin 0.3%/dexamethasone 0.1% otic suspension, 4 drops into the affected ear twice daily for 7 days—combined with oral analgesics (ibuprofen 400–600 mg every 6 hours or acetaminophen 650–1000 mg every 6 hours) for pain control. 1

Why Topical Therapy Is the Definitive First-Line Treatment

• Topical antibiotic drops achieve clinical cure rates of 65–90% within 7–10 days for uncomplicated acute otitis externa, regardless of which FDA-approved agent is used. 1
• Topical therapy delivers drug concentrations 100–1,000 times higher at the infection site compared to oral antibiotics, explaining the superior outcomes (77–96% cure rate versus only 30–67% for oral antibiotics). 1
• Pseudomonas aeruginosa and Staphylococcus aureus cause approximately 98% of acute otitis externa cases, and topical fluoroquinolones provide excellent coverage against both pathogens. 1
• Oral antibiotics should NOT be prescribed as initial therapy for uncomplicated acute otitis externa—yet 20–40% of patients inappropriately receive them. 1

Specific Prescription Details

Topical Antibiotic Selection

• Ciprofloxacin 0.3%/dexamethasone 0.1% otic suspension is the preferred choice because it combines antimicrobial activity with anti-inflammatory effects that accelerate pain relief and reduce canal edema. 1, 2
• The steroid component (dexamethasone) is significantly more effective than antibiotic alone, with an odds ratio of 11 (95% CI 2.00–60.57) for clinical cure. 1
• Dosing: 4 drops into the affected ear twice daily for 7 days. 2
• Alternative if ciprofloxacin/dexamethasone is unavailable: ofloxacin 0.3% otic solution, 5 drops twice daily for 7–10 days. 1

Why This Specific Agent?

• In a 21-year-old with no drug allergies and presumably intact tympanic membrane, any FDA-approved topical preparation is acceptable—but ciprofloxacin/dexamethasone has demonstrated superior clinical and microbiologic cure rates (90.9% vs. 83.9%) compared to neomycin/polymyxin B/hydrocortisone in head-to-head trials. 3
• The twice-daily dosing of ciprofloxacin/dexamethasone improves adherence compared to three-times-daily regimens. 3

Essential Pre-Treatment Step: Aural Toilet

• Before prescribing drops, perform aural toilet to remove debris, cerumen, and inflammatory material—medication cannot penetrate through obstructing debris to reach infected tissue. 1
• Use gentle suction, dry mopping with cotton-tipped applicators, or irrigation with body-temperature water, saline, or hydrogen peroxide. 1
• If severe canal edema prevents drop entry or the tympanic membrane cannot be visualized, place a compressed cellulose wick to facilitate drug delivery. 1

Pain Management Is Essential

• Assess pain severity and prescribe appropriate analgesics—pain in acute otitis externa can be severe and requires systematic management. 1
• For mild-to-moderate pain: ibuprofen 400–600 mg every 6 hours or acetaminophen 650–1,000 mg every 6 hours. 1
• For severe pain: consider short-term opioid-containing analgesics for the initial 48–72 hours. 1
• Pain typically improves within 48–72 hours of starting topical therapy. 1
• Do NOT use topical anesthetic drops (e.g., benzocaine)—they are not FDA-approved for active infections and may mask treatment failure. 1

Patient Instructions for Proper Drop Administration

• Warm the bottle in your hands for 1–2 minutes before use to prevent dizziness from instilling cold drops. 1
• Have someone else administer the drops if possible—only 40% of patients self-administer correctly during the first 3 days. 1
• Lie with the affected ear upward and instill 4 drops to fill the ear canal completely. 1, 2
• Remain in this position for 3–5 minutes (use a timer) to allow penetration. 1
• Apply gentle to-and-fro movement of the pinna or press the tragus in/out to eliminate trapped air. 1
• After sitting up, wipe off excess drops but leave the canal open to dry—do not trap moisture. 1

Activity Restrictions and Patient Education

• Keep the ear dry during treatment—cover the ear canal with an earplug or petroleum jelly-coated cotton before showering or hair washing. 1
• Avoid swimming and water exposure until the infection resolves. 1
• Do not insert cotton swabs or any objects into the ear canal. 1
• Complete the full 7-day course even if symptoms resolve early to prevent relapse. 1
• If you taste the eardrops, inform your doctor immediately—this indicates a tympanic membrane perforation. 1

When Oral Antibiotics ARE Indicated (Not in This Case)

Reserve systemic antibiotics for specific circumstances only: 1

• Extension of infection beyond the ear canal (periauricular cellulitis or swelling)
• Diabetes mellitus or immunocompromised state
• Severe canal edema preventing adequate topical delivery despite wick placement
• Failure to improve after 48–72 hours of appropriate topical therapy

When systemic antibiotics are indicated, use oral fluoroquinolones (ciprofloxacin 500 mg twice daily) to cover P. aeruginosa and S. aureus. 1

Reassessment Criteria

• Reassess the patient within 48–72 hours if symptoms do not improve. 1
• Common causes of treatment failure include: 1
  • Inadequate drug delivery due to canal obstruction or poor adherence
  • Allergic contact dermatitis from topical agents (especially neomycin)
  • Fungal co-infection (otomycosis)
  • Incorrect diagnosis (e.g., chronic suppurative otitis media, necrotizing otitis externa)
• If symptoms persist beyond 7 days, continue drops until resolution for a maximum of 14 days total. 1

Critical Pitfalls to Avoid

• Do NOT prescribe oral antibiotics for uncomplicated acute otitis externa—this is the most common error. 1
• Do NOT skip aural toilet before prescribing drops—medication cannot penetrate debris. 1
• Do NOT use aminoglycoside-containing drops (neomycin/polymyxin B) if tympanic membrane integrity is uncertain—they are ototoxic. 1
• Do NOT provide inadequate pain management—this is a strong guideline recommendation. 1
• Do NOT use ear candles—they have no proven efficacy and can cause harm including hearing loss and tympanic membrane perforation. 1