Refer a patient with otitis externa to an ear, nose, and throat (ENT) specialist if there is suspected malignant otitis externa or a serious complication, depending on clinical judgement NICE CKS.
Seek specialist advice or arrange referral if symptoms persist despite optimal management in primary care, or if there is severe infection not responding to management, especially in elderly or immunocompromised patients NICE CKS.
If external ear canal occlusion due to discharge, swelling, or debris prevents effective topical treatment, or if cellulitis extends beyond the external ear canal which cannot be managed in primary care, referral is indicated NICE CKS.
Consider referral if contact sensitivity to neomycin or other aminoglycosides is suspected, and specialist tissue sampling or culture may be needed to rule out cholesteatoma or malignancy NICE CKS.
In cases of recurrent episodes of acute otitis externa or persistent symptoms despite adequate treatment, referral to ENT is recommended NICE CKS.
Additionally, if symptoms are not responding to management in primary care or are severe, or if there is external ear canal occlusion or cellulitis extending beyond the canal, referral should be considered NICE CKS.