Which term describes a severe allergic reaction requiring emergency treatment?

Anaphylaxis is a life-threatening allergic reaction that occurs rapidly after exposure to an allergen. This reaction can cause a range of symptoms, including difficulty breathing, swelling of the throat and mouth, a rapid drop in blood pressure, hives, and gastrointestinal symptoms. Because of the severity and the potential for rapid progression, anaphylaxis requires immediate medical attention, typically in the form of epinephrine administration and emergency services.

The other terms provided do not involve allergic reactions. Akathisia refers to a state of restlessness and an inability to stay still, often as a side effect of certain medications. Addiction describes a chronic condition characterized by compulsive drug seeking and use, even in the face of negative consequences. Abuse typically refers to the harmful or hazardous use of substances. None of these terms convey the urgency or seriousness of a severe allergic reaction like anaphylaxis does.