Immediate Fluoxetine Hypersensitivity With Predominant Airway and Oropharyngeal Symptoms in an Adolescent.

Fluoxetine is a widely prescribed selective serotonin reuptake inhibitor in children and adolescents. Hypersensitivity reactions are rare and poorly characterized in this population. We report the case of a 17-year-old female who developed acute throat tightness with perceived oropharyngeal swelling and respiratory symptoms within 30 minutes of the first dose of fluoxetine, in the absence of cutaneous manifestations. Symptoms improved with bronchodilator therapy. Basophil activation testing demonstrated drug-induced activation, and an oral drug provocation test reproduced symptoms, confirming hypersensitivity. Previously reported pediatric cases included delayed urticaria, angioedema, and drug rash with eosinophilia and systemic symptoms. In contrast, this case highlights an immediate reaction predominantly affecting the airway. This report expands the known clinical spectrum of fluoxetine hypersensitivity reactions and emphasizes that the absence of cutaneous manifestations does not exclude drug allergy.