Management of simple insect bites: where's the evidence?
Many insects bite in order to obtain a blood meal and, in the process, inject the victim with saliva that may contain a number of substances, some of which can be immunogenic. The consequences of insect bites include local reactions, immune (allergic) reactions including anaphylaxis, and secondary bacterial infections (e.g. impetigo, cellulitis). Although insect bites are perceived to be common in the UK, the exact incidence is difficult to estimate since most are likely to go unreported: only those causing the more serious reactions are seen in primary care settings. Simple insect bites are those that are not accompanied or followed by anaphylactic shock or systemic infection. Many preparations for the treatment of insect bites, including antihistamines and topical corticosteroids, are available for purchase over the counter (OTC) in the UK. However, there is a lack of evidence for the efficacy of these treatments and, in general, recommendations for treatment are based on expert opinion and clinical experience. This article reviews the evidence for the management of simple bites by insects commonly encountered in the UK, but excludes ticks, mites and lice.