The 16-year-old boy who took an Amoxicillin capsule and immediately complained of swelling to his tongue and lips, difficulty breathing with wheezing was suffering from an anaphylactic reaction to the antibiotic. Anaphylaxis is a systemic hypersensitivity reaction to an antigen mediated by the immunoglobulin E (IgE) antibody (Reber et al., 2017). Anaphylaxis is the most severe type of allergic reaction requiring immediate emergency medical attention to prevent death from respiratory failure (Justiz-Vaillant et al., 2021).
Genetics may have predisposed him to this type of allergy. Children with one parent with an IgE allergy have a 40% chance of developing an allergy. If both of the child’s parents have this type of allergy, the chance may increase to 80% (McCance & Huether, 2019).
The immediate symptoms of swelling to the lips and tongue with audible wheezing is due to a massive histamine release. H1 receptors are mainly on smooth muscle in the bronchi and will cause constriction, cough, wheezing, dyspnea, and hypoxia; the H2 receptors will cause inflammation (Reber et al., 2017).
The physiologic response with an anaphylactic reaction is sudden, unexpected, catastrophic if untreated. Peavy & Metcalf (2008) report this type of allergy usually starts from the activation of mast cells and basophils that crosslink with IgE. When an antigen is present along with the presence of IgE antibodies, mast cells and basophils release histamine and leukotrienes which are mostly responsible for all of the symptoms (Peavy & Metcalf, 2008). Even though histamine is the major cause of the symptoms, the primary treatment is injectable epinephrine. The epinephrine will cause vasoconstriction, increase heart rate, and block further histamine release. H1/H2 antihistamines and corticosteroids are used, but not as the primary treatment (Reber et al., 2017).
This scenario is classic of a severe anaphylactic reaction. Even if it started later, which is rare but it can, the presence of swelling to the tongue, and audible wheezing is indicative of this diagnosis, leading me to the same response.
Justiz Vaillant, A. A., Vashisht R., Zito. P. M. (2021). Immediate hypersensitivity reactions. In: StatPearls. Treasure Island, FL: StatPearls Publishing. Retrieved from
McCance, K. L. & Huether, S. E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed.). St. Louis, MO: Mosby/Elsevier.
Peavy, R. D., & Metcalfe, D. D. (2008). Understanding the mechanisms of anaphylaxis. Current Opinion in allergy and clinical immunology 8(4), 310–315.
Reber, L. L., Hernandez, J. D., Galli, S. J. (2017). The pathophysiology of anaphylaxis. The Journal of allergy and clinical immunology, 140(2), 335–348.