We present a patient with a non-IgE-mediated urticaria reaction to the morphine injection which was tinted blue due to prior injection of Patent Blue V dye into her left breast. Clinicians should be aware of these types of reaction to morphine.
K E Y W O R D Sdirect histamine release, morphine injection, non-IgE-mediated localized reaction, Patent Blue V F I G U R E 1 Localized blue wheals following morphine injection on the right arm 924 | KOUMAKI And ORTOn erythema, pruritus, and sometimes pseudoallergic anaphylactoid reactions. 1,2 In our case, the patient experienced a non-IgE-mediated urticarial reaction to the morphine injection which was tinted blue due to prior subareolar injection of Patent Blue V dye into her left breast.