A plausible mechanism of apnea and airway obstruction in these patients is a functional anesthesia of the larynx with inability to clear a stimulus resulting in tissue edema and airway obstruction.

1.9% of hereditary angioedema attacks involved the larynx, which could be fatal. Patients took sebetralstat 11.5 minutes after these attacks began. 96% of patients saw relief after one dose of ...