What causes Panic and Agoraphobia?

A number of factors work together to cause panic attacks and panic disorder and the particular combination will vary from person to person, although these can be understood as a chain of factors of broadly three types that progressively build up to produce panic:

Vulnerability

Some people are vulnerable to developing panic attacks and agoraphobia as a result of their constitution and life experiences. Risk factors in early life can include genetic inheritance, the nature of family relationships and childhood trauma. Temperamental factors, such as an ingrained tendency to worry, together with continuing stress over a period of time, can also make people predisposed to panic attacks. 

Triggers

Immediate stresses or triggers can bring on a sudden panic attack. A common 'trigger' is 'over breathing' or hyperventilation - many panic attack sufferers experience shallow breathing during an attack, but some people may actually be hyperventilating chronically (two common signs are excessive sighing or yawning).  Hyperventilation results in typical symptoms of panic, such as dizziness and weakness, which are then misinterpreted and trigger a full-blown panic attack. Another crucial trigger is the misuse of alcohol, drugs or other stimulants, as these can provoke the nervous system and exacerbate anxiety.

Perpetuating factors

There are a number of influences that keep the panic process going, often leading to a vicious cycle in which panic attacks are made worse or brought on more frequently.  These can be divided into psychological, social and physical factors:

Psychological factors

People prone to high levels of stress, fear of illness and catastrophic thinking often have lingering worries after a panic attack subsides that they are ill, insane or dying; constant apprehension re-triggers the nervous system into a state of emergency, a panic attack ensues, and the vicious cycle is set up.

Social Factors

Social crises that lead to a build-up of tension before the onset of panic disorder, such as pressure at work or home, may continue after the attacks begin, causing the sufferer continuing stress and creating a high risk of panic attacks occurring.

Physical Factors

Bouts of illness such as the 'flu or viral infections, poor general health and the effects of drugs can all mimic anxiety and thus intensify panic symptoms. 

Panic attacks can also be caused by other anxiety disorders, such as social phobia, obsessive-compulsive disorder or post-traumatic stress disorder.