Explains obsessive-compulsive disorder (OCD), including possible causes and how you can access treatment and support. Includes tips for helping yourself, and guidance for friends and family.
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There are different theories about why OCD develops. None of these theories can fully explain every person's experience, but researchers suggest that these are likely to be involved in causing OCD:
Even though we don't fully understand what causes OCD, it can still be successfully treated. You can read more about treatments here.
Some theories suggest that OCD is caused by personal experience. For example:
Some biological theories suggest that a lack of the brain chemical serotonin may have a role in OCD. However, it's unclear whether this is a cause or an effect of the condition.
Studies have also looked at genetic factors and how different parts of the brain might be involved in causing OCD, but have found nothing conclusive.
This information was published in May 2019. We will revise it in 2022.
References and bibliography available on request.
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