About This Page
This is a clinician-written, evidence-based summary aligned to the 2026 MLA Content Map. It is intended for medical students and junior doctors preparing for the UKMLA. Always cross-reference with NICE guidance, local protocols, and clinical judgement.
The Bottom Line
- Inflammation of the external ear canal — most commonly bacterial (Pseudomonas aeruginosa, Staphylococcus aureus)
- Key clinical feature: tragal tenderness — distinguishes OE from AOM
- First-line: topical antibiotic/steroid drops (Otomize spray or ciprofloxacin/dexamethasone)
- Ear wick if canal too swollen to admit drops — remove after 48–72 hours
- Malignant (necrotising) OE: elderly/diabetic/immunocompromised — IV antibiotics + urgent ENT
- Keep ears dry, avoid cotton buds, non-ototoxic drops if TM perforation
Overview
Otitis externa is an inflammatory condition of the external auditory canal skin and subdermis. Acute OE (<3 weeks) is most commonly bacterial — Pseudomonas aeruginosa and Staphylococcus aureus predominate. Chronic OE (>3 months) may be fungal (Aspergillus, Candida) or secondary to eczema/psoriasis. Precipitated by disruption of the cerumen barrier from water exposure, cotton bud trauma, or hearing aid use.
Epidemiology
Affects 1–3% of the population annually. Peak in summer (water exposure). Risk factors: swimming, hearing aids, cotton buds, eczema, diabetes, immunosuppression. More common in adults than children. Recurrence in up to 30%.
Clinical Features
Symptoms
Otalgia — often severe, worse on jaw movement
Pruritus in the ear canal
Ear discharge
Conductive hearing loss from canal oedema
Rapid onset (within 48 hours)
Deep boring pain in elderly diabetic — suspect malignant OE
Cranial nerve palsies (VII, IX–XII) — necrotising OE
Signs
Tragal tenderness — pain on pressing tragus or pulling pinna
Canal erythematous, oedematous, narrowed with debris
TM usually normal — distinguishes from AOM
Fungal OE: white strands (Candida) or black dots (Aspergillus)
Granulation tissue at bony-cartilaginous junction — malignant OE
Investigations
First-line
Clinical diagnosisHistory and otoscopy — no routine investigations
Second-line
Ear swab (MC&S)If not responding after 7 days or malignant OE suspected
Specialist
CT temporal boneIf malignant OE suspected — bony erosion assessment
ESR/CRPRaised in malignant OE — monitoring treatment response
Management
NICE CKS Otitis Externa, 20241
Self-care
- Keep ears dry, avoid cotton buds
- Analgesia: paracetamol or ibuprofen
2
Topical treatment (first-line)
- Aural toilet (microsuction) to remove debris
- Otomize spray or ciprofloxacin/dexamethasone drops for 7 days
- If TM perforation: ciprofloxacin-based (avoid aminoglycosides)
- Acetic acid 2% spray (EarCalm) for mild cases
3
Swollen canal
- Ear wick if too oedematous for drops
- Apply drops onto wick 3–4 times daily, remove after 48–72 h
4
Refractory/severe
- Fungal: clotrimazole 1% drops after swab confirmation
- Oral antibiotics only if cellulitis beyond canal
- Malignant OE: urgent ENT — IV ciprofloxacin + piperacillin-tazobactam for 6–8 weeks
Complications
- Malignant OE: Life-threatening temporal bone infection in elderly/diabetic — Pseudomonas, cranial nerve palsies, osteomyelitis
- Chronic OE: Canal stenosis from repeated inflammation
- Perichondritis: Pinna cartilage infection
UKMLA Exam Tips
- 1Tragal tenderness = OE. No tragal tenderness + TM changes = AOM
- 2Malignant OE: elderly + diabetes + granulation tissue + CN palsies → Pseudomonas, IV abx, CT
- 3No aminoglycoside drops if TM perforated — use ciprofloxacin
- 4Aspergillus = black spores, Candida = white strands → clotrimazole
- 5Systemic antibiotics NOT needed for uncomplicated OE
- 6Ear wick for swollen canal — classic exam scenario
practicetest your knowledge on otitis externaApply what you've learnt with UKMLA-style questions from the iatroX Q-Bank — ent and beyond.
open q-bank regional clinical guidance
Otitis Externa: guidance by region
Recommendations, thresholds and pathways can differ. Open the page written for the jurisdiction you need.