OCD Awareness Week 13th-19th October: Understanding the Overlap of OCD and PTSD and How Cognitive Behavioural Therapy Can Help

Leah Fung – EMDR & CBT Therapist, CBT Supervisor in Guildford, London Bridge and Online

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Obsessive-Compulsive Disorder (OCD) and Post-Traumatic Stress Disorder (PTSD) are both mental health conditions that can cause significant distress in an individual’s life.

While they are typically discussed as separate diagnoses, there is a growing recognition that these disorders often occur together, particularly when OCD symptoms develop in response to trauma.

For OCD Awareness Week, this blog explores the connection between OCD and PTSD, how these conditions may impact a person and how cognitive behavioural therapy (CBT) can provide a structured approach to addressing both difficulties simultaneously.

Understanding OCD and PTSD: The Basics

OCD is characterised by intrusive, unwanted thoughts (obsessions) that cause anxiety and compulsions (such as repetitive behaviours or mental acts) aimed at reducing distress. For example, someone may fear that they’ve left the door unlocked and repeatedly check it to reduce their anxiety, even when they rationally know it’s locked. These cycles of obsessive thinking and compulsive actions can severely impact daily functioning.

PTSD occurs after a person has experienced, witnessed or learned about a traumatic event. It presents in symptoms like re-experiencing the trauma as though it is happening now in the form of flashbacks or nightmares. There may also been experiences of avoiding trauma related reminders or triggers, heightened arousal or vigilance and negative changes in mood or thought processes (cognition). People with PTSD often feel as though the trauma could recur and the body remains in a state of alertness long after the event has passed.

When trauma is at the root of OCD, the traumatic experience may lead to both the re-experiencing symptoms of PTSD and the intrusive obsessive thoughts of OCD. Compulsions, rituals or avoidance behaviours may serve as coping mechanisms to manage the anxiety and sense of danger that persists long after the trauma event.

A Cognitive Behavioural Perspective of OCD and PTSD

Cognitive Behavioural Therapy (CBT) is a structured, evidence-based form of psychotherapy that focuses on identifying and changing thought processes and behaviours that maintain your difficulties (e.g. OCD and PTSD). The theory is that our thoughts, emotions, physiological symptoms and behaviours are interconnected and by modifying any part of these areas, you will notice shifts in the other processes.

Cognitive Behavioural Therapy Cycle for blog on OCD Awareness Week — Cognitive Behavioural Therapy Cycle

In OCD, the mind overestimates danger, leading to obsessive thoughts and compulsive actions that seek to neutralise or prevent the perceived threat. For instance, a person might believe that if they don’t perform a specific ritual (like checking that the house door is locked multiple times), something catastrophic will happen and it will be their fault.

In PTSD, the brain remains hyper-focused on the trauma experiences, interpreting non-threatening situations as dangerous. The individual may feel constant hypervigilance, often struggling with intrusive memories and a perceived lack of safety.

In people with PTSD, the autonomic nervous system may become dysregulated, remaining in a state of over-activation (fight/flight response), with even minor stressors triggering a heightened sense of danger or a under-activation/shutdown (freeze response).

For people with both PTSD and OCD, the compulsions may act as an attempt to regain control over the heightened state of arousal, giving the individual a (false) sense of temporary relief from the ongoing internal threat.

These nervous system responses align with what’s happening cognitively. The individual’s mind and body are locked in a feedback loop, where obsessive thoughts fuel anxiety, compulsions attempt to mitigate that anxiety, and the body’s physiological response remains activated. From a cognitive-behavioural perspective, avoidance and compulsions reinforce the cycle, never allowing the individual to learn that the feared outcomes are unlikely to occur and the behaviours intended to cope with feelings of anxiety, prevent the nervous system from finding a state of regulation and safety.

How OCD and PTSD Impacts Daily Life

Living with both OCD and PTSD can be overwhelming. Intrusive thoughts or memories of the trauma can overlap with the obsessive fears typical of OCD. For example, a person might have an intrusive memory of the trauma (a hallmark of PTSD), which then spirals into obsessive fears (OCD) about future harm or danger. This can lead to constant checking behaviours, avoidance of places or situations that remind them of the trauma, or compulsive mental rituals aimed at keeping danger at bay. The person may feel like they are constantly at risk, either from external threats (due to PTSD) or from internal fears about their own thoughts or actions (due to OCD).

This cycle of hypervigilance and compulsive behaviour not only disrupts daily routines but can also lead to a profound sense of isolation. Friends and family may struggle to understand why the individual continues to engage in certain behaviours and the person themselves may feel frustrated by their inability to control their thoughts and reactions. Over time, these behaviours can dominate their life, impacting their mood, enjoyment of life, connection or personal fulfilment.

How CBT Can Address Both OCD and PTSD

CBT is effective in treating both OCD and PTSD because it directly addresses the patterns of behaviours and thought processes that maintain these difficulties.

For PTSD, making sense of the trauma experiences, a component of CBT, helps individuals gradually face trauma-related memories or triggers and integrate updated information that they know now in a manageable and supportive environment. This process reduces the emotional intensity and ‘nowness’ associated with the trauma memory and helps individuals learn that they can tolerate the memories without being overwhelmed.

For OCD, Exposure and Response Prevention (ERP) is used to confront intrusive thoughts without engaging in compulsions. This helps individuals break the link between obsessive thoughts and compulsive behaviours, providing opportunities to learn what happens when the compulsions are not performed. Over time, ERP helps reduce the frequency and intensity of both the obsessions, compulsions and anxiety.

CBT also incorporates cognitive restructuring, where individuals learn to identify and challenge thoughts and beliefs that fuel both PTSD and OCD. For example, in PTSD, a person may believe that because they were harmed once or by particular people that they are at constant risk of being harmed again or by everyone.

In OCD, they may believe that their intrusive thoughts have real-life consequences and if they don’t engage with the compulsions then something bad would happen or that it reflects something bad about themselves. Cognitive restructuring can help to examine the accuracies of these thoughts and to consider alternative more workable perspectives.

Skills like grounding, self-soothing, imagery and breathwork can be integrated with CBT to help regulate the nervous system. These techniques help shift the body from a state of hyperarousal or hypoarousal when this is problematic, supporting the cognitive work done in therapy. By targeting both the physiological and cognitive aspects of these difficulties, CBT can help individuals regain control over their thoughts, behaviours, emotions and bodily responses, leading to lasting change.

CBT offers a comprehensive framework for addressing both OCD and PTSD, providing tools to break the cycle of avoidance, fear and compulsive behaviour. Through the therapy process and learning further skills to respond to thoughts, emotions, physical sensations and behaviours, therapy can help individuals manage the symptoms of both difficulties, ultimately improving their quality of life.

Book in a Call To Discuss Your Therapy

If you are experiencing these difficulties and you are ready to explore changes that you can make, book into a free no obligation 20 minutes call here: https://yourtherapywithleah.co.uk/contact-cognitive-behavioural-therapist-guildford/