Panic Attack:

A panic attack is the sudden onset of intense apprehension and fearfulness in the absence of actual danger, accompanied by physical symptoms, like heart palpitations, difficulty breathing, chest pain or discomfort, choking or smothering sensations, sweating, and dizziness. The attack occurs in a discrete period of time and often involves fears of going crazy, losing control, or dying. Attacks may occur in the context of any of the anxiety disorders or other mental disorders (mood disorders, substance-related disorders). See Panic Disorder