Panic attacks

The main symptoms are having unexpected and recurring panic attacks, and also  worrying about having another panic attack. One of the symptoms of a panic attack is an increased heart  rate. A panic attack may happen because of a particular situation (something that the person fears or  wants to avoid), or it may have no obvious cause. People who have panic attacks often change their  behavior as a consequence of the attack, which may develop into phobias such as agoraphobia (a fear of  being in places or situations that are difficult to escape from).