Panic attacks are sudden episodes of intense anxiety, occurring when no real danger exists. The person feels overwhelmed with terror, as the body reacts with symptoms such as heart palpitations, chest pain, breathing difficulties, shaking, sweating, nausea, faintness, numbness, and weakness. Often, the individual fears that he or she is having a heart attack, going "crazy" or "losing control".

Typically, when symptoms first begin, the person goes to the hospital emergency room or to the family physician, and is told that there is nothing physically wrong. Without proper help, the condition progresses and agoraphobia may develop.