<unk>  sufferers usually have a series of intense episodes of extreme anxiety during<unk>  attacks. These attacks typically last about ten minutes, and can be as short-lived as 1–5 minutes, but can last twenty minutes to more than an hour, or until helpful intervention is made.<unk>  attacks can last up to an hour, and the intensity and symptoms of<unk>  may vary. In some cases, the attack may continue at unabated high intensity or seem to be increasing in severity. Common symptoms of an attack include rapid heartbeat, perspiration, dizziness, dyspnea, trembling, uncontrollable fear such as: the fear of losing control and going crazy, the fear of dying and hyperventilation. Other symptoms are a sensation of choking, paralysis, chest pain, nausea, numbness or tingling, chills or hot flashes, faintness, crying and some sense of altered reality. In addition, the person usually has thoughts of impending doom. Individuals suffering from an episode have often a strong wish of escaping from the situation that provoked the attack. The anxiety of<unk>  is particularly severe and noticeably episodic compared to that from generalized anxiety disorder.<unk>  attacks may be provoked by exposure to certain stimuli (e.g., seeing a mouse) or settings (e.g., the dentist's office). Nocturnal<unk>  attacks are common in people with<unk> . Other attacks may appear unprovoked. Some individuals deal with these events on a regular basis, sometimes daily or weekly. Limited symptom attacks are similar to<unk>  attacks but have fewer symptoms. Most people with<unk>  experience both<unk>  attacks and limited symptom attacks. Interoceptive Studies investigating the relationship between interoception and<unk>  have shown that people with<unk>  feel heartbeat sensations more intensely when stimulated by pharmacological agents, suggesting that they experience heightened interoceptive awareness compared to subjects without<unk> .
Panic disorder
Hyperthyroidism
Depression 
Cardiovascular disease
Late life depression
Hypochondriasis
Blood phobia
Anxiety disorder