Treatment of Otitis Externa
The recommended first-line treatment for uncomplicated otitis externa is topical fluoroquinolone ear drops, such as ciprofloxacin 0.2% or ofloxacin 0.3%, administered once daily for 7 days. 1
Diagnostic Features
- Rapid onset (within 48 hours) in the past 3 weeks
- Symptoms: otalgia (ear pain), itching, fullness
- Signs: tenderness of tragus/pinna, ear canal edema/erythema
- Predominantly bacterial etiology (98% of cases in North America)
Treatment Algorithm
1. First-Line Treatment for Uncomplicated Otitis Externa
- Topical antibiotic therapy:
- Fluoroquinolone ear drops (ciprofloxacin 0.2% or ofloxacin 0.3%)
- Dosing for ofloxacin 0.3%: 2
- Children (6 months to 13 years): 5 drops once daily for 7 days
- Adults (≥13 years): 10 drops once daily for 7 days
- Administration technique:
- Warm solution by holding bottle in hand for 1-2 minutes
- Patient should lie with affected ear upward
- Maintain position for 5 minutes after instillation
2. Pain Management
- Acetaminophen or NSAIDs for immediate pain relief
- Pain typically improves within 48 hours of starting treatment
3. Special Considerations
- Fungal otitis externa: Azole antifungals (clotrimazole or miconazole)
- Necrotizing (malignant) otitis externa: Systemic antibiotics and close monitoring
- Systemic antibiotics: Reserved for:
- Infection spread beyond ear canal
- Patients at risk of rapidly progressing infection
Treatment Efficacy
- Fluoroquinolone ear drops have cure rates of 77-96% 1
- Once-daily ofloxacin for 7 days has shown 91% cure rate (95% in children, 88% in adolescents/adults) 3
- 68% of patients are cured within 7 days of starting treatment 3
Important Considerations and Pitfalls
Avoid These Common Mistakes:
- Neomycin-containing products as first-line therapy: Can cause sensitization in 5-15% of patients with chronic otitis externa 1
- Inserting cotton-tipped swabs into ear canal: Can cause trauma and worsen infection 1
- Using oral antibiotics for uncomplicated cases: Results in lower cure rates, more systemic side effects, and contributes to antibiotic resistance 1
- Discontinuing treatment prematurely: Complete the full 7-day course even if symptoms improve earlier 1
- Using ear candles: No proven benefit and can cause harm 1
Risk Factors Requiring Special Attention:
- Diabetes: Higher risk for severe infections, fungal otitis, delayed healing
- Immunocompromised state
- Prior head/neck radiation: Requires delicate debridement, higher risk of poor healing
- Coagulopathy
- Narrow ear canal
- Eardrum perforation
Prevention of Recurrence
- Avoid excessive moisture in ear canal
- Dry ears thoroughly after water exposure
- Consider prophylactic acidifying solutions after water exposure
- Avoid inappropriate cleaning methods
Evidence Considerations
The recommendation for fluoroquinolone ear drops is strongly supported by the American Academy of Otolaryngology-Head and Neck Surgery guidelines 1. While older studies showed efficacy of neomycin/polymyxin B combinations 4, more recent evidence indicates declining susceptibility to these agents 5, with fluoroquinolones maintaining consistent efficacy 3, 6. Once-daily dosing of ofloxacin has demonstrated excellent compliance (98%) and efficacy comparable to more frequent dosing regimens 3.