Panic disorder is a common mental disorder. According to statistics, about 4% of Hong Kong people are currently suffering from panic disorder. People with panic disorder have recurrent unexpected panic attacks - sudden periods of intense discomfort that last for 10-30 minutes. Panic disorder can cause great problems to individuals by affecting their work and daily life. 

​

Agoraphobia is a common condition in panic disorder. People with agoraphobia will avoid crowds (such as subways), situations in which escape might be difficult (e.g. long-distance buses) or unfamiliar places. 

​

The psychology and medical field believe that panic disorder and agoraphobia are caused by an interaction between biological, psychological and environmental factors. Among them, genetics inheritance is the most important factor. Other related factors include chemical imbalance in the brain (biological), faulty cognition (psychology) and childhood experience (environmental). 

People with panic disorder or agoraphobia will experience different “fight-or-flight responses” on the physical level (see below for examples). These physical sensations will lead to behaviours such as fleeing from the scene, or taking precautions. In the long run, it leads to worries and negative perceptions over these responses, and eventually form a vicious cycle that leads to greater distress.