Otitis externa is a common inflammatory (normally infective) condition affecting the external ear canal. It can usually be treated successfully in the primary care setting with ear drops.
Focus of the review
There is a wide range of available topical preparations used in clinical practice to treat otitis externa, including antiseptic agents, antibiotics, corticosteroids, antifungals, and combinations of these. The main purpose of this review is to identify the evidence base to support the use of these treatments in uncomplicated otitis externa.
Comments on evidence
We found numerous studies on the medical treatment of otitis externa but the majority are of poor quality, underpowered, lack blinding, or have inadequate follow-up to be of clinical value. There are also multiple potential interventions, which are often used in combination, so the evidence available to assess and compare individual interventions is generally limited.
Search and appraisal summary
The update literature search for this review was carried out from the date of the last search, October 2007, to October 2013. For more information on the electronic databases searched and criteria applied during assessment of studies for potential relevance to the review, please see the Methods section. After deduplication and removal of conference abstracts, 38 records were screened for inclusion in the review. Appraisal of titles and abstracts led to the exclusion of 28 studies and the further review of 10 full publications. Of the 10 full articles evaluated, one systematic review was added at this update.
This review also considers the improved efficacy of topical agents over oral antibiotics in uncomplicated otitis externa. In addition to topical ear drops, aural toilet (with microsuction or ear mopping) and the use of ear wicks to aid administration of topical therapy in patients with oedematous ear canals constitute common treatment interventions. Aural toilet is usually performed in the secondary care setting, often when topical treatment alone has failed. This treatment practice is included in this review. However, given the methodological difficulties of performing robust trials with a procedural intervention, the evidence is sparse.
Substantive changes at this update
Aluminium acetate (topical) One systematic review added. Evidence re-evaluated. Categorisation unchanged (likely to be beneficial).
Antibacterials (topical; likely to be beneficial with or without corticosteroids) One systematic review added. Evidence re-evaluated. Categorisation unchanged (likely to be beneficial).
Antifungals (topical; with or without corticosteroids) One systematic review added. Categorisation unchanged (unknown effectiveness).
Corticosteroids (topical) One systematic review added. Evidence re-evaluated. Categorisation changed from 'likely to be beneficial' to ''unknown effectiveness'.
Acetic acid (topical) One systematic review added. Categorisation unchanged (unknown effectiveness).
Antibiotics (oral) One systematic review added. Categorisation unchanged (unknown effectiveness).
Antibiotics (oral) plus anti-infective agents (topical) Title clarified. One systematic review added. Categorisation unchanged (unlikely to be beneficial [by consensus]).
Specialist aural toilet One systematic review added. Evidence re-evaluated. Categorisation changed from 'unknown effectiveness' to 'likely to be beneficial' by consensus.
INTRODUCTION: Otitis externa is thought to affect 10% of people at some stage, and can present in acute, chronic, or necrotising forms. Otitis externa may be associated with eczema of the ear canal, and is more common in swimmers, in humid environments, in people with narrow ear canals, in hearing-aid users, and after mechanical trauma. METHODS AND OUTCOMES: We conducted a systematic review and aimed to answer the following clinical question: What are the effects of empirical treatments for otitis externa? We searched: Medline, Embase, The Cochrane Library, and other important databases up to October 2013 (BMJ Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). RESULTS: Nine studies were included. We performed a GRADE evaluation of the quality of evidence for interventions. CONCLUSIONS: In this systematic review, we present information relating to the effectiveness and safety of the following interventions: oral antibiotics, specialist aural toilet, topical acetic acid, topical aluminium acetate, topical antibacterials, topical antifungals, topical corticosteroids, and combinations of these agents.