What is the medical term for a severe allergic response that can be life-threatening?

The term for a severe allergic response that can be life-threatening is anaphylactic shock. This condition is characterized by a rapid onset of symptoms that can affect multiple body systems, including the respiratory and cardiovascular systems. Anaphylactic shock is often triggered by allergens, such as certain foods, medications, or insect stings, and requires immediate medical intervention, often with the administration of epinephrine.

While chronic allergy refers to prolonged allergic reactions, and type I hypersensitivity is the broader immunological mechanism behind such reactions, neither specifically denotes the acute, life-threatening nature of anaphylactic shock. Seasonal allergies refer to more common, less severe allergic reactions that occur at specific times of the year due to pollen or mold, making them distinct from the critical emergency that anaphylactic shock represents.