Contributor: Ricky Dhaliwal, MD Educational Pearls: Angioedema in anaphylaxis Histamine and mast cell-mediated pathway Treatment: First line: epinephrine for vasoconstriction and bronchodilation Second line: H1 and H2 antihistamines such as Benadryl and famotidine ACE inhibitor-induced angioedema Different pathway from anaphylaxis ACE inhibitor-induced angioedema is mediated by bradykinins Therefore, anaphylaxis medications are not beneficial in patients with ACE inhibitor-induced angioedema Leading cause of drug-induced angioedema in the US Patients most commonly present with swelling of the lips, tongue, or face Treatment: Airway management: varies depending on the severity and progression of the presentation If awake nasointubation is required, LMX is a 5% lidocaine water-soluble solution that provides anesthesia to the oropharynx Medications: Icatibant is a synthetic bradykinin B2-receptor antagonist that can be used in acute treatment Tranexamic acid (TXA) inhibits the plasmin-dependent formation of bradykinin, but the data on this treatment are mixed and limited Fresh frozen plasma (FFP) is thought to degrade high levels of bradykinin with subsequent resolution of angioedema Discontinue ACE inhibitor References Bork K, Wulff K, Hardt J, Witzke G, Staubach P. Hereditary angioedema caused by missense mutations in the factor XII gene: clinical features, trigger factors, and therapy. J Allergy Clin Immunol. 2009 Jul;124(1):129-34. doi: 10.1016/j.jaci.2009.03.038. Epub 2009 May 27. PMID: 19477491. Bova M, Guilarte M, Sala-Cunill A, Borrelli P, Rizzelli GM, Zanichelli A. Treatment of ACEI-related angioedema with icatibant: a case series. Intern Emerg Med. 2015 Apr;10(3):345-50. doi: 10.1007/s11739-015-1205-9. Epub 2015 Feb 10. PMID: 25666515. Karim MY, Masood A. Fresh-frozen plasma as a treatment for life-threatening ACE-inhibitor angioedema. J Allergy Clin Immunol. 2002 Feb;109(2):370-1. doi: 10.1067/mai.2002.121313. PMID: 11842313. Pathak GN, Truong TM, Chakraborty A, Rao B, Monteleone C. Tranexamic acid for angiotensin-converting enzyme inhibitor-induced angioedema. Clin Exp Emerg Med. 2024 Mar;11(1):94-99. doi: 10.15441/ceem.23.051. Epub 2023 Aug 1. PMID: 37525579; PMCID: PMC11009700. Simons FE. First-aid treatment of anaphylaxis to food: focus on epinephrine. J Allergy Clin Immunol. 2004 May;113(5):837-44. doi: 10.1016/j.jaci.2004.01.769. Erratum in: J Allergy Clin Immunol. 2004 Jun;113(6):1039. Dosage error in article text. PMID: 15131564. Summarized by Meg Joyce, MS2 | Edited by Meg Joyce & Jorge Chalit, OMS4 Donate : https://emergencymedicalminute.org/donate/
