Anaphylaxis: the acute episode and beyond

#### Summary points Anaphylaxis is an alarming medical emergency,1 2 3 not only for the patient or caregiver, but also sometimes for the healthcare professionals involved. Although it is thought of as uncommon, the lifetime prevalence is estimated at 0.05-2%,4 5 and the rate of occurrence is increasing. Hospital admissions, although uncommon, are also increasing, as are admissions to critical care units.6 7 Many anaphylaxis episodes now occur in community settings.8 Accurate community based population estimates are difficult to obtain because of underdiagnosis, under-reporting, and miscoding, as well as use of different anaphylaxis definitions and different methods of case ascertainment in the populations studied.5 Although death from anaphylaxis seems to be uncommon, it is under-reported.9 In this article, we draw on evidence from randomised controlled trials, quasi-experimental and other observational studies, and systematic reviews. We also reference key evidence based international and national anaphylaxis guidelines and their updates.1 2 10 11 #### Sources and selection criteria We based this review on Medline and …