Aetiology

Theories concerning the aetiology of panic disorder fall into two groups:

• biochemical theories:
  
  
• there may be some abnormality in neurotransmitter function; the following compounds may cause panic attacks in patients more easily than in the general population:
  • yohimbine
  • lactate
  • imipramine
    
    
• dysregulation of the autonomic nervous system:
  • the sympathetic nervous system is activated during an attack but there is little evidence that autonomic dysfunction is the primary problem
    
    
• hyperventilation:
  • hyperventilation does not occur in all patients with panic attacks
    
    
• cognitive theories:
  
  
• patients with panic attacks have a tendency to attribute the physical symptoms of anxiety to a serious organic disease
  
  
• there is a cognitive spiral of anxiety causing physical symptoms, a fear of serious organic disease and more anxiety