What causes PTSD?

Unlike other psychiatric disorders, PTSD always has a traceable cause — a traumatic event. PTSD develops when you experience or witness the traumatic event, and your reaction to the event causes intense fear, helplessness or horror.

Common events that can lead to PTSD are:

  • A natural disaster (flood, tornado, hurricane).
  • An accident (car, plane, train, boat).
  • A physical attack (assault, rape).
  • Military combat.

Not everyone who experiences or witnesses a traumatic event develops PTSD. The exact reason as to why one person develops PTSD while another person does not is unknown, however research suggests that PTSD may be caused by a chemical imbalance in the brain. Studies also suggest that after exposure to a traumatic event, women and people with a prior history of depression or anxiety are more likely to develop PTSD.