The exact cause of agoraphobia is unknown, but researchers believe that the condition could be the result of a combination of genetic and psychological factors.

Genetic predisposition

A number of studies that have been conducted suggest that certain genes can increase the likelihood that certain people will develop agoraphobia.

This genetic predisposition may affect people in several different ways. One theory is that certain genes may cause an imbalance in brain chemicals, known as neurotransmitters. This may affect your mood, making you more prone to anxiety-related conditions, such as agoraphobia.

Another theory is that certain genes may make you more sensitive to sensory input, such as sounds, sights, and smells. Being exposed to too much sensory input - for example, when shopping in a busy supermarket, may increase your levels of stress and anxiety.

Psychological factors

Possible psychological factors that may trigger agoraphobia include:

• a traumatic childhood experience, such as the death of a parent, or
• a previous history of drug or alcohol abuse,
• experiencing a stressful event, such as a bereavement, the loss of a job, or
• having a history of previous mental illnesses, such as depression, anorexia, or bulimia, and
• being in an unhappy relationship, or in a relationship where the partner is 'over-controlling'.

However, some cases of agoraphobia have no obvious contributory psychological factors.