What are the signs of severe contrast allergic reactions?

Severe allergic reactions to contrast media can present with signs that indicate a serious and potentially life-threatening event. Among these, facial edema, or swelling of the face, is a common manifestation, as it reflects an intense immune response. Anaphylactic shock is a critical condition characterized by a sudden drop in blood pressure and severe respiratory distress, making it a hallmark of extreme allergic reactions. Hypotension, or low blood pressure, occurs as part of the systemic vascular response during anaphylaxis, where the body releases a barrage of chemical mediators that lead to vasodilation and increased vascular permeability.

In the context of severe reactions, it is crucial to recognize these signs promptly to enable immediate medical intervention. Understanding these symptoms allows healthcare professionals to act swiftly to manage the situation, including administering medications like epinephrine that can counteract the effects of anaphylaxis.

The other options include symptoms that may indicate allergic reactions, but they do not describe the severity associated with life-threatening conditions. Moderate urticaria and facial swelling alone may indicate a less severe reaction, while diffuse erythema, throaty irritation, and dyspnea suggest an allergic response but not necessarily the intense crisis posed by anaphylaxis. Wheezing, nasal stuffiness, and