ALLERGIC EMERGENCIES Kristina Dawson, PharmD, BCPS Objectives for Pharmacists Describe the immunologic pathways to cause an allergic response Identify the most common triggers to cause Choose the appropriate treatment for The speaker has no conflicts of interest to disclose Objectives for Technicians Describe what causes an allergic reaction Identify the most common triggers to cause Describe possible treatments for Patient Case SM is a 31 y/o female with a PMH of atopia, allergic rhinitis, asthma, eczema, and depression. Immunization Hx: influenza vaccine every year x 8 years Received influenza vaccine then briskly walked to office (~5 min walk) ~15 min later Subjective symptoms: impending doom feeling Objective symptoms: red rash on neck and chest, chest tightness, throat tightness, shortness of breath, altered mental status Anaphylaxis Lifetime prevalence ~0.05%-2% Potentially underestimated Definition of is complex; difficult to assess in epidemiological studies Several guidelines World Allergy Organization (WAO) American Academy of Allergy, Asthma and Immunology (AAAAI) and American College of Allergy, Asthma and Immunology (ACAAI) European Academy of Allergy and Clinical Immunology (EAACI) Definition of Anaphylaxis WAO AAAAI / ACAAI EAACI A serious lifethreatening generalize or systemic hypersensitivity An acute lifethreatening systemic reaction with varied mechanisms, clinical reaction and a presentations, ti & serious allergic severity that results reaction that is rapid in from the sudden onset & might cause release of mediators death from mast cells & basophils A severe lifethreatening generalize or systemic hypersensitivity reaction Lieberman P, et al. J Allergy Clin Immunol. 2010;126:477-480; Camargo CA, et al. J Allergy Clin Immunol. 2007;120:131-136; Sheehan WJ, et al. J Allergy Clin Immunol. 2009;124:850-852. Simons et al. International consensus on (ICON). WOA Journal. 2014; 7:9 1
Triggers Influencing Factors Pathophysiology Clinical Presentation Onset: Any allergen: within 2 hours Food allergen: within 30 min Parenteral medication or insect sting: < 30 min Multiple organ systems affected: Skin/urticaria (80-90%) Respiratory tract (70%) More common in pediatrics Gastrointestinal tract (30-45%) Cardiovascular (10-45%) More common in adults Central nervous system (10-15%) Top Health. Food Allergy Doctor insights on Top Health. https://www.healthtap.com/topics/food-allergy. Accessed May 1, 2015. Biphasic Allergic Reaction A second reaction occurring after initial recovery Occur: 1 to 72 hours later Usually: 4 to 12 hour Occurs in up to 20% presenting with More severe than initial reaction Account for 25% of fatal/near-fatal food reactions and 23% of drug/biologic reactions Rarely occurs without initial hypotension or airway obstruction Marco HK, et al. Clinical Spectrum of Food Allergies: a comprehensive review. Clinic Rev Allerg Immunol. 2014; 43: 225-40 Marco HK, et al. Clinical Spectrum of Food Allergies: a comprehensive review. Clinic Rev Allerg Immunol. 2014; 43: 225-40 2
Signs and Symptoms Signs and Symptoms Gastrointestinal Abdominal pain, nausea, vomiting, diarrhea, dysphagia Cardiovascular system Chest pain Tachycardia, bradycardia (less common), other arrhythmias, palpitations Hypotension, feeling faint, urinary or fecal incontinence, shock Cardiac arrest Central nervous system Aura of impending doom, uneasiness, throbbing headache (pre-epinephrine), p p altered mental status, dizziness, confusion, tunnel vision Other Metallic taste Cramps & uterine bleeding from contractions in pregnancy Skin, subcutaneous tissue, mucosa Flushing, itching, urticaria, angioedema, morbilliform rash, pilor erection Periorbital itching, erythema & edema, conjunctival erythema, tearing Itching of lips, tongue, palate, and external auditory canals; and swelling of lips, tongue, & uvula Itching of genitalia, palms, & soles Respiratory Nasal itching, congestion, rhinorrhea, sneezing Throat itching & tightness, dysphonia, hoarseness, stridor, dry staccato cough Lower airways: increase respiratory rate, SOB, chest tightness, deep cough, wheezing/bronchospasm, decease peak expiratory flow Cyanosis Respiratory arrest Anaphylaxis Definition Differential Diagnosis 1. Acute onset of illness with cutaneous and/or mucosal involvement AND at least one of the following: a. Respiratory compromise b. Cardiovascular compromise 2. Two or more of the following occur rapidly after exposure to a likely allergen a. Involvement of skin or mucosa b. Respiratory compromise c. Cardiovascular compromise d. Persistent GI symptoms 3. Hypotension after exposure to known allergen Acute asthma Syncope Anxiety/panic attach Acute generalize urticaria Aspiration of a foreign body Cardiovascular event (MI, PE) Neurologic event (seizure, CVA) Shock Nonallergic angioedema Systemic capillary leak syndrome Red man syndrome Pheochromacytoma Flushing syndrome Ben-Shoshan M, Clarke AE. Anaphylaxis: past, present and future. Allergy. 2011; 66: 1 14 Epinephrine FIRST LINE TREATMENT Dosing: Adults: epinephrine (1:1000) 0.3 mg IM Pediatrics: epinephrine 0.01 mg/kg (up to 0.3 mg) IM Given intramuscular in the anterolateral thigh Mechanism of action: Epinephrine β2- α1- α2- Vasoconstriction Peripheral vascular resistance Mucosal edema Insulin release Bronchodilation Vasodilation Mediator release β1- Inotropy Chronotropy Simons, KJ et al. Epinephrine and its use in : current issues. Curr Opin Allergy Clin Immunol. 2010;10:354-361. 3
Intramuscular vs. Subcutaneous Epinephrine in Adults 6-way cross over study Healthy 18-35 y/o men Adverse Effects Pallor Tremors Palpitations HA Shivers Epinephrine Absorption in Pediatrics Single dose, parallelgroup 17 children (4-12 y/o) Ave age: 8 + 1 y/o Epinephrine SQ 0.01mg/kg (max 0.3 mg) Ave wt.: 32 + 3 kg Mean dose: 0.27 + 0.04 mg EpiPen IM 0.3 mg Ave wt.: 27 + 2 kg Estelle R, et al. Epinepherine absorption in adults: intramuscular versus subcutaneous injection. J Allergy Clin Immunol. 2001; 108: 871-3 Estelle F, et al. Epinephrine absorption in children with a history of. J Allergy Clin Immunol. 1998; 101:33-7 Epinephrine Absorption in Pediatrics Adverse Effects Tremor (16/17) Pallor (14/17) Headache (4/17) Tingling extremities (3/17) SubQ Epi IM Epi Epinephrine and Obesity Chart review of pts presenting to ED for Focus on total number of epinephrine doses and BMI categorization 321 pts in 4 different EDs 261 children 60 adults No difference in need for additional doses in: Adults vs. children (P=0.94) When administered adjunct medications (P=0.38) Including corticosteroids Obesity vs. non-obesity (OR 1.22; 95% CI 0.77-1.93; P=0.4) Adjusted for age and sex Estelle F, et al. J Allergy Clin Immunol. 1998; 101:33-7 Rudders, SA et al. Obesity is not a risk factor for repeat epinephrine use in the treatment of. J Allergy Clin Immunol 2012;130:1216-8 Outdated EpiPen Epinephrine is inherently unstable Oxidized by O 2 & light Turning pink - brown due to the formation of melanin 28 EpiPen & 6 EpiPen Jr 1-90 mo past expiration Bioavailability in rabbits Epinephrine content by spectrophotometric method SECOND SECOND-LINE TREATMENTS Estelle, F et al. Outdated EpiPen and EpiPen Jr autoinjectors: past their prime? J Allergy Clin Immunol. 2000; 105: 1025-30 4
Glucocorticoid Steroids Adult: hydrocortisone 200 mg IV/IM x 1 or methylprednisolone 50 100 mg IV/IM x 1 Pediatrics: hydrocortisone 1-2 mg/kg IV/IM x 1 (max 100 mg) or methylprednisolone 1-2 mg/kg IV/IM x 1 (max 60 mg) Cochrane systemic review of randomized controlled trials Often used inappropriately as first-line medications in place of epinephrine in ED Potentially prevent biphasic Found zero randomized controlled trials assessing use in Cannot recommend for or against the use of steroids in Other Second-line Treatments Beta-2 agonist Adults and Pediatrics: albuterol 2-6 puffs or 2.5 mg nebulized q 20 min prn or 15 mg/hr continuous nebulization H1- and H2-antihistamines H1: Adults: diphenhydramine 50 mg IV/IM/PO x 1 H1: Pediatrics: diphenhydramine 1-1.25 mg/kg IV/IM/PO (max 50 mg) H2: Adults: famotidine 20 mg IV/IM/PO x 1 H2: Pediatrics: famotidine 0.5 mg/kg IV/IM/PO x 1 (max 20 mg) O2 supplementation Fluid resuscitation Choo KJL, et al. Glucocorticoids for treatment of.. Cochrane Database of Systematic Reviews. 2012; 4:CD007596 After- Management Consensus of all three guidelines: All patients should be given a script for epinephrine auto-injector Education from a trained healthcare professional Recognizing signs and symptoms Avoiding triggers Appropriate use of epinephrine auto-injector Medical alert ID Follow-up with an allergist/immunologist trained in Allergen sensitivity testing Desensitization protocols Self Assessment Question Which cell type is responsible for the monophasic or initial allergic response? A. Mast cell B. Histamine i C. Eosinophil D. Neutrophil Simons et al. International consensus on (ICON). WOA Journal. 2014; 7:9 Self Assessment Question In patient SM, who a 31 y/o female with a PMH of atopia, allergic rhinitis, asthma, eczema, depression. She just received the flu shot prior briskly walked back to her office prior and subsequently experiencing symptoms of an acute allergic emergency. What predisposing factor or trigger put her at risk for? A. Previous exposure to the flu vaccine B. Exercise C. Depression D. All of the above Self Assessment Questions What is the best treatment option for SM? A. Epinephrine 0.3 mg IM in anterolateral thigh and go back to work B. Epinephrine 0.3 mg SQ in anterolateral thigh and go straight to the emergency room C. Epinephrine 0.3 mg IM in anterolateral thigh and go to the emergency room D. This is not and should be treated with glucocorticoid steroids and an H1-antihistamine 5
References 1. Lieberman P, et al. The diagnosis and management of practice parameter: 2010 update.j Allergy Clin Immunol. 2010;126:477-480 2. Camargo CA, et al. Regional differences in EpiPen prescriptions in the United States: the potential role of vitamin D.J Allergy Clin Immunol. 2007;120:131-136; 3. Sheehan WJ, et al. Higher incidence of pediatric in northern areas of the United States.J Allergy Clin Immunol. 2009;124:850-852 4. Simons et al. International consensus on (ICON). WOA Journal. 2014; 7:9 5. Simons et al. World allergy organization guidelines for the assessment and management of. WAO Journal. 2011; 4:13-37 6. Top Health. Food Allergy Doctor insights on Top Health. https://www.healthtap.com/topics/food-allergy. Accessed May 1, 2015 7. Marco HK, et al. Clinical Spectrum of Food Allergies: a comprehensive review. Clinic Rev Allerg Immunol. 2014; 43: 225-40 8. Ben-Shoshan M, Clarke AE. Anaphylaxis: past, present and future. Allergy. 2011; 66: 1 14 9. Simons, KJ et al. Epinephrine and its use in : current issues. Curr Opin Allergy Clin Immunol. 2010;10:354-361 10. Estelle R, et al. Epinepherine absorption in adults: intramuscular versus subcutaneous injection. J Allergy Clin Immunol. 2001; 108: 871-3 11. Estelle F, et al. Epinephrine absorption in children with a history of. J Allergy Clin Immunol. 1998; 101:33-7 12. Rudders, SA et al. Obesity is not a risk factor for repeat epinephrine use in the treatment of. J Allergy Clin Immunol 2012;130:1216-8 13. Estelle, F et al. Outdated EpiPen and EpiPen Jr autoinjectors: past their prime? J Allergy Clin Immunol. 2000; 105: 1025-30 14. Choo KJL, et al. Glucocorticoids for treatment of. Cochrane Database of Systematic Reviews. 2012; 4:CD007596 ALLERGIC EMERGENCIES Kristina Dawson, PharmD, BCPS 6