What Is Complex Trauma and How Do I Know if I Have It?

Updated: Jul 28


A young man with complex trauma sits in a corner with his head in his heads

Virtually everyone has experienced trauma, but for those with complex trauma, the brain and nervous system are rewired to be in a constant state of fight or flight. Here’s how to know if this is happening to you.


Key takeaways:

  • Up to 70% of adults will experience a traumatic event in their lifetime; 20% will go on to develop a trauma-response-related disorder.

  • While you may intellectually understand that the trauma occurred in the past, for people with complex trauma, the trauma response continues in the present.

  • When trauma is chronic, prolonged, or extreme, the nervous system might stay chronically activated and struggle to return to a state of balance.

  • Complex trauma can affect your mood, thoughts, behaviors, and relationships.

  • Multiple forms of therapy can help you heal complex trauma.

Have you ever experienced something traumatic? If so, you’re not alone. Statistics show that up to 70% of adults have experienced a traumatic experience in their lifetime. Nearly everyone has had an experience that has activated their “fight or flight” stress response, whether it was something like an illness, car accident, or being a survivor of childhood abuse.


Approximately 20% of people will go on to develop a trauma-response-related disorder following an activating traumatic event. Trauma isn’t necessarily what happens, but how the body responds. While many people intellectually recognize that the activating events are in the past, sometimes your body can’t make the distinction. When this happens, it’s as if the event is no longer a memory, but happening currently. This is known as complex trauma.


What is complex trauma?


Mental health professionals have only recently started to recognize and discuss the intricacies of complex trauma. The Diagnostic and Statistical Manual of Mental Disorders, 5th edition, which is the guidebook clinicians use to diagnose mental health disorders, does not yet recognize complex trauma as an official diagnosis. But its existence is recognized by many frontline clinicians who treat trauma. Researchers now believe that more than 3% of people meet the criteria for complex trauma.


Complex trauma is also known as complex post-traumatic stress disorder or C-PTSD. Trauma may be a result of a singular event, a series of events, or happen over a prolonged period. After a singular traumatic event, the body (particularly the nervous system) can usually return to a state of relaxation. If trauma compounds or is prolonged, it will become more difficult for the nervous system to regulate itself. When the body has a difficult time turning off its “fight or flight” response, complex trauma can develop, leaving the body in a state of perpetual “fight or flight.”


How does it occur?


When an activating event occurs, the brain’s limbic system goes into action. This is called the “fight or flight” response. During this state of emergency, nonessential bodily functions such as digestion and sleep shut down. Your body is flooded with stress hormones like cortisol so that you can cope with the perceived threat by either fighting, running (flight), or freezing (think of a possum playing dead).


When the threat is gone, your body begins to relax and the parasympathetic nervous system, or “rest and digest” kicks in. However, in people with complex trauma, the body is unable to fully restore balance. The limbic system continues to stay activated as a coping mechanism to remain safe in the face of repeated threats or danger. It is essentially remaining in “survival mode,” and over time,