This page presents both the symptoms of a panic attack as well as the symptoms of the stress response (or flight or flight response). As you will see, the symptoms are almost identical because the underlying physiology is the same.
Definition and symptoms of a panic attack
A panic attack is defined as an abrupt surge of intense fear or intense discomfort that reaches a peak within minutes, and during which time 4 (or more of the following symptoms occur: palpitations, pounding heart, or accelerated heart rate; sweating; trembling or shaking; sensations of shortness of breath or smothering; feeling of choking; chest pain or discomfort; nausea or abdominal distress; feeling dizzy, unsteady, lightheaded, or faint; derealization (feelings of unreality) or depersonalization (being detached from oneself); fear of losing control or going crazy; fear of dying; numbness or tingling sensations; and/or chills or hot flushes.
The stress response (fight or flight)
The stress response is activated when an organism perceives it is in danger, and it better enables it to either fight or flee. Adrenaline is released which causes the following:
Accelerated heart rate (which can result in palpitations or a pounding heart).
Increased muscle tension (which can result in chest pain or discomfort, choking sensations, trembling or shaking, and/or numbness or tingling sensations).
Changes in breathing rate (e.g., faster and deeper) (which can result in hyperventilation and cause sensations of shortness of breath or smothering, feeling dizzy, unsteady, lightheaded, or faint, numbness or tingling sensations, and derealization (feelings of unreality) or depersonalization (being detached from oneself).
Redirection of blood flow from the extremities to the major muscle groups (resulting in chills or hot flushes).
Redirection of energy from the digestive system to systems necessary for fight or flight (resulting in nausea or abdominal distress).
Panic attack versus the stress response
Physiologically, panic attacks and the stress response are the same phenomenon. The only symptoms that are unique to a panic attack are a "fear of losing control or going crazy" and a "fear of dying," and these pertain to how a person interprets the possible implications of the other symptoms.