Cimetidine in the treatment of refractory anaphylaxis

After preoperative intubation and administration of intravenous cefuroxime, a 48-year-old white female developed anaphylactic shock that was refractory to the usual therapeutic measures but was responsive to treatment with intravenous cimetidine. Beta-lactam sensitivity was subsequently confirmed by skin testing. Cimetidine, which antagonizes arterial H2 receptors, may be useful in the treatment of anaphylaxis refractory to the usual resuscitative measures.     

Cardiovascular aspects of anaphylaxis: implications for treatment and diagnosis

PURPOSE OF REVIEW: Anaphylactic cardiovascular collapse can be resistant to treatment with epinephrine (adrenaline) and, in some cases, diagnostic uncertainty compromises follow-up care. The purpose of this review is to examine recent studies relevant to the management and diagnosis of this condition. RECENT FINDINGS: Nausea, vomiting, incontinence, diaphoresis, dyspnoea, hypoxia, dizziness and collapse are associated with hypotension. Relative bradycardia (falling heart rate despite hypotension) is a consistent feature of hypotensive insect sting anaphylaxis and may represent a non-specific physiological response to severe hypovolaemia in conscious individuals. Upright posture has been found to be associated with death from anaphylaxis. Animal studies have found the intramuscular route for epinephrine is ineffective, intravenous boluses temporarily effective, but intravenous infusions of epinephrine are able to reverse anaphylactic shock. In one animal model, antihistamines were found to be harmful. A prospective human study provides evidence for the efficacy of treatment with intravenous epinephrine infusion and fluid (volume) resuscitation. Case reports support the use of the vasoconstrictors metaraminol, methoxamine and vasopressin if adrenaline is ineffective. Repeated measurements of mast cell tryptase are more sensitive and specific than a single measurement for the diagnosis of anaphylaxis. SUMMARY: Current evidence supports use of the supine/Trendelenburg position, epinephrine by intravenous infusion and aggressive volume resuscitation. If these fail, atropine should be considered for severe bradycardia and potent vasoconstrictors may be useful. To confirm the diagnosis of anaphylaxis, serial measurements of mast cell tryptase may be preferable to a single measurement.     

Emergency department anaphylaxis: A review of 142 patients in a single year.

BACKGROUND: There are few data on the incidence, clinical features, and management of patients with acute anaphylaxis presenting to the emergency department. We investigated all presentations to one department during the course of a year to improve current awareness of this medical emergency. OBJECTIVE: The purpose of the study was to describe the clinical features, management, and outcome of anaphylaxis presentations to a single Australian adult emergency department in a single year, 1998-1999. METHODS: This was a retrospective, case-based study of adult patients (>or=13 years of age) attending a single emergency department in Brisbane, Australia, during the year 1998-1999. The medical records of 304 patients satisfying the relevant discharge diagnostic codes were studied. We determined incidence, sex ratio, age, clinical features, management, disposal, asthma prevalence, and causes in patients presenting with acute allergic reactions and anaphylaxis. RESULTS: In all, 162 emergency department patients with acute allergic reactions and 142 emergency department patients with anaphylaxis, including 60 whose anaphylaxis was severe, were seen during the year, for an anaphylaxis presentation incidence of 1 in 439. One patient died; this gave a case fatality rate of 0.70%. Cutaneous features were present in 94% of the patients with anaphylaxis. Of those with severe anaphylaxis, 35% had dizziness/syncope before hospital presentation, 25% laryngeal edema, and 21.7% systolic hypotension on hospital presentation. A cause was recognized in 73% of the anaphylaxis cases; most commonly, the causative agent was a drug, insect venom, or food. Adrenaline was used in 57% of the severe cases before hospital presentation or in the hospital. The emergency department alone definitively cared for 94% of all patients, though only 43% severe anaphylaxis cases were referred for follow-up. CONCLUSION: The emergency department anaphylaxis presentation incidence of 1 in 439 cases is greater than previously recognized, though death remains rare. In three fourths of cases, a precipitant was identified, a fact that emphasizes the need for a detailed initial history. Definitive management in the emergency department alone is possible in most cases, provided that the appropriate use of adrenaline and the need for allergy clinic follow-up are appreciated.     

Successful treatment of cold-induced urticaria/anaphylaxis with anti-IgE

A case of a girl who presented at age 12 years with idiopathic cold urticaria is described. Her reactions to the cold became progressively more severe over a period of approximately 2 years, despite therapy with H1 antagonists and a type 1 receptor for cysteinyl leukotrienes receptor antagonist. She began to experience systemic symptoms on immersion in ocean water. She was atopic and had moderate persistent asthma. A trial of anti-IgE resulted in complete resolution of her urticaria and its associated manifestations. These findings should prompt a reexamination of the potential pathogenetic role played by IgE and its high-affinity receptor on mast cells in idiopathic cold urticaria.     

Impact of public health interventions for food allergy prevention on rates of infant anaphylaxis

BackgroundEleven percent of Australian infants have confirmed food allergy. We hypothesized earlier introduction may lead to higher rates of infant anaphylaxis, irrespective of whether the overall rate of food allergy in the population was ultimately reduced.ObjectiveTo determine whether a public health campaign, targeting earlier introduction of allergenic foods, affected rates of infant anaphylaxis.MethodsData were obtained from St John Ambulance (SJA) Western Australia and Western Australian emergency departments (ED) on infant (≤12 months) anaphylaxis over a 5-year period (July 1, 2015 to June 30, 2020). Adrenaline administration data were collected in the SJA dataset. Poisson regression was undertaken to assess trends in anaphylaxis over time. Segmented regression analysis was undertaken to assess differences in anaphylaxis rates before and after intervention.ResultsThe SJA and ED datasets included 172 and 294 events, respectively, coded as infant anaphylaxis. Rates of infant anaphylaxis increased over time for both SJA and ED datasets, with a 1-year increase rate ratio of 1.21 (95% confidence interval, 1.09-1.35; P value < .01) and 1.11 (95% confidence interval, 1.02-1.20; P = .01), respectively. Segmented regression indicated no significant difference in rates after intervention. Adrenaline was not coded as being administered in 109 of the 172 anaphylaxis events.ConclusionRates of infant anaphylaxis increased over the 5-year reporting period; however, there was no clear increase related to the timing of the public health campaign implementation. Reported adrenaline use was suboptimal. Assessing rates of food allergy in all age groups is required to determine whether there has been an overall reduction in food allergy owing to the intervention.     

Adrenaline for the treatment of anaphylaxis: cochrane systematic review

Background:  Anaphylaxis is a serious allergic reaction that is rapid in onset and may cause death. Adrenaline is recommended as the initial treatment of choice for anaphylaxis.
Objectives:  To assess the benefits and harms of adrenaline in the treatment of anaphylaxis.
Methods:  We searched the Cochrane Central Register of Controlled Trials (CENTRAL) ( The Cochrane Library 2007, Issue 1), MEDLINE (1966 to March 2007), EMBASE (1966 to March 2007), CINAHL (1982 to March 2007), BIOSIS (to March 2007), ISI Web of Knowledge (to March 2007) and LILACS (to March 2007). We also searched websites listing ongoing trials: http://www.clinicaltrials.gov/ , http://www.controlledtrials.com and http://www.actr.org.au/ and contacted pharmaceutical companies and international experts in anaphylaxis in an attempt to locate unpublished material. Randomized and quasi-randomized controlled trials comparing adrenaline with no intervention, placebo or other adrenergic agonists were eligible for inclusion. Two authors independently assessed articles for inclusion.
Results:  We found no studies that satisfied the inclusion criteria.
Conclusions:  On the basis of this review, we are unable to make any new recommendations on the use of adrenaline for the treatment of anaphylaxis. In the absence of appropriate trials, we recommend, albeit on the basis of less than optimal evidence, that adrenaline administration by intramuscular injection should still be regarded as first-line treatment for the management of anaphylaxis.     

First-aid treatment of anaphylaxis to food: focus on epinephrine

Avoiding food triggers for anaphylactic reactions (severe acute systemic allergic reactions) is easier said than done. Most episodes of anaphylaxis to food occur unexpectedly in the community in the absence of a health care professional. All individuals at risk should therefore have an emergency action plan in place. The cornerstone of first-aid treatment of anaphylaxis is epinephrine injected intramuscularly in the vastus lateralis muscle (lateral aspect of the thigh). In this review, we focus on epinephrine. We examine a therapeutic dilemma: the issue of epinephrine dose selection in an individual for whom no optimal fixed-dose auto-injector formulation exists, and a therapeutic controversy: the issue of epinephrine injection versus an oral H1-antihistamine in anaphylaxis episodes that appear to be mild. The pharmaceutical industry could address the first of these issues by providing a wider range of epinephrine fixed doses in easy-to-use auto-injectors, or by providing adjustable epinephrine doses in auto-injectors. The second issue could be addressed in part by development of alternative routes of epinephrine administration for the first-aid, out-of-hospital treatment of anaphylaxis.