Obsessive compulsive disorder (OCD) is a mental health condition in which unwanted thoughts, images or urges (obsessions) cause intense anxiety, and the person repeats an action or a mental act (a compulsion) to reduce it. Relief is brief, the obsession returns, and the cycle repeats.
Key points
- OCD has two parts: obsessions, unwanted thoughts, images or urges that cause distress, and compulsions, acts repeated to reduce it.
- It is not a preference for neatness. Order is one theme among several, and the tidiness stereotype makes OCD harder to recognise.
- In England, 2.2% of adults met the criteria for OCD in 2023/4.
- Compulsions are sometimes carried out entirely in the mind, often called Pure O, though the compulsions are hidden rather than absent.
- NICE recommends CBT including exposure and response prevention (ERP), with SSRI medication as an alternative or an addition.
Symptoms
- Obsessions: unwanted thoughts, images or urges that intrude; fear of harm, contamination or illness; a need for symmetry; doubt about whether something was done correctly.
- Outward compulsions: washing, checking locks or appliances, arranging until it feels right, asking for reassurance.
- Mental compulsions: repeating words or numbers silently, producing a neutralising thought, reviewing memories to check what happened.
Causes and risk factors
- The cause is not fully understood. Family history, differences in serotonin signalling.
- Life events such as bullying, abuse or bereavement, and personality traits such as a strong sense of responsibility.
Treatment
- CBT including exposure and response prevention (ERP): approaching the trigger and not carrying out the compulsion.
- Mild impairment: low-intensity CBT including ERP. Moderate: a choice between an SSRI and more intensive CBT. Severe: combined SSRI and CBT.
- SSRIs named by NICE: fluoxetine, fluvoxamine, paroxetine, sertraline and citalopram, continued at least 12 months if effective.
When to speak to a professional
- Obsessions and compulsions take up an hour or more on most days.
- You are avoiding places, people or tasks to prevent the thoughts.
- Work, study, sleep or relationships are affected.
- You are hiding the behaviour, or seeking reassurance many times a day.
If you need help now: Samaritans, call 116 123, free, 24/7. Shout, text SHOUT to 85258. NHS 111, then choose the mental health option. Call 999 if anyone is in immediate danger.