What is anaphylaxis?

Anaphylaxis is a severe allergic reaction characterized by a rapid onset of symptoms that can be life-threatening. It typically manifests with symptoms such as difficulty breathing due to airway constriction, swelling in areas like the face, throat, or lips, and a significant drop in blood pressure, which can lead to shock. The body's immune system reacts strongly to an allergen, causing the release of chemicals such as histamine that trigger these severe symptoms.

In contrast to the symptoms mentioned in the other options, which refer to milder reactions or unrelated conditions, anaphylaxis requires immediate medical intervention, commonly in the form of an epinephrine injection, to reverse the potentially fatal effects. Understanding this distinction is vital for quick recognition and response, as anaphylaxis escalates rapidly and can result in serious complications if not treated promptly.