OCD (obsessive compulsive disorder)

What are the symptoms of OCD?

OCD has two main parts. An obsession is a thought or mental image that intrudes again and again, often bringing a wave of anxiety or unease with it. A compulsion is your response: something physical or mental that you carry out to try to settle that feeling. You can have obsessions without compulsions, or the other way round.

Common obsessions

• Contamination: worrying about germs, dirt or illness
• Harm: fearing you might hurt yourself or someone else, on purpose or by accident
• Perfection and symmetry: needing things arranged, counted or done in an exact way, and feeling something is wrong if they aren't
• Responsibility: fearing something bad will happen because you forgot to check something
• Unwanted intrusive thoughts: distressing thoughts about violence, sex or religion that feel completely out of character
• Relationships or identity: persistent doubts about a partner's feelings, or about who you are.

Common compulsions

• Washing or cleaning far more than needed
• Checking things repeatedly, such as locks, switches or appliances
• Arranging or ordering items until they feel right
• Counting, or repeating an action a set number of times
• Silently repeating words or phrases in your head
• Asking others for reassurance.

These symptoms often impact your day and feel impossible to stop. Any relief a compulsion brings tends to be short-lived, since the anxiety soon returns. Many people recognise that their thoughts or routines don't make logical sense, but still feel driven to carry them out.

Research also links OCD to a higher risk of suicidal thoughts, so if things ever feel unbearable, please reach out for support straight away: Samaritans are free to call, any time, on 116 123.

What causes OCD, and who is at risk?

There's no single known cause. Research points to a mix of genetics, brain chemistry and life experience.

• A family history of OCD, particularly in a parent or sibling
• Differences in brain activity or in serotonin, a brain chemical linked to mood
• A difficult or traumatic life experience, including bullying, abuse or neglect
• A major life event, such as having a baby or a bereavement
• A personality that tends towards perfectionism, high personal standards, or feeling especially answerable for other people's wellbeing
• Being under significant stress.

OCD can start at any age, including in young children, though it most often begins around puberty or early adulthood. It's unusual for symptoms to start for the first time after your mid-30s. Roughly 1 in 45 people will develop OCD over the course of their lifetime, and men and women are affected in broadly similar numbers.

Are there different types of OCD?

OCD isn't split into separate diseases in the way some physical conditions are, but obsessions and compulsions do tend to cluster around a few recognisable themes.

• Contamination and cleaning: fear of germs or dirt, paired with washing or cleaning rituals
• Checking: fear that harm will happen because something wasn't checked properly, paired with repeated checking
• Symmetry and ordering: a need for things to be arranged, counted or done precisely, paired with ordering, counting or repeating rituals
• Unwanted intrusive thoughts: distressing thoughts of a violent, sexual or religious nature, often paired with mental rather than physical rituals
• Hoarding-type difficulty discarding possessions, though this is now usually diagnosed as its own separate condition, hoarding disorder, rather than as OCD.

How is OCD diagnosed?

There's no blood test or scan for OCD. Diagnosis is made by a suitably qualified professional, such as a GP, psychiatrist or psychologist, based on a conversation about your thoughts, behaviours and how much they're affecting your life.

• You have obsessions, compulsions, or both
• They take up a significant amount of time, often an hour or more each day
• They cause you distress or get in the way of work, school or daily life
• They aren't better explained by a medicine, substance or another health condition.

Your provider may also use a specific severity questionnaire, known as the Yale-Brown Obsessive Compulsive Scale, to help track how you're doing over time. On average, people wait around seven to eight years after symptoms start before reaching out to a doctor about them, so if this sounds like you, know that it's never too late to ask for help.

How is OCD treated?

Non-surgical treatment

• ERP, or exposure and response prevention: a specific form of cognitive behavioural therapy (CBT) where you gradually face the situations that trigger your obsessions while resisting the urge to carry out your usual compulsion
• Medicine, usually an antidepressant called an SSRI (selective serotonin reuptake inhibitor). It can be a couple of months before the full benefits appear (around eight to twelve weeks), and treatment often continues for at least 12 to 24 months once symptoms have settled
• Clomipramine, an alternative antidepressant used if SSRIs alone don't help, though it tends to cause more side effects
• Using ERP and medicine together, which often works better than either approach alone
• Additional therapies such as ACT (acceptance and commitment therapy) or DBT (dialectical behaviour therapy), and neuromodulation using TMS (transcranial magnetic stimulation), a treatment that uses magnetic pulses to change brain activity, for people who haven't responded to other options.

Surgical treatment

Surgery is kept as a genuine last resort, used only when OCD remains severe despite thorough therapy and medicine. Deep brain stimulation, which uses an implanted device to send electrical signals to specific areas of the brain, is the main surgical option, and doesn't involve destroying any brain tissue. In the UK, this kind of surgery can only go ahead once you've been through a complete course of therapy with a qualified cognitive behavioural specialist.

When should I see a doctor?

• Obsessive thoughts or compulsive behaviours are affecting your work, relationships or daily routine
• You're spending an hour or more a day on these thoughts or behaviours
• You've been putting off getting help out of embarrassment; there's no more reason to feel that way about OCD than about any other illness.

If OCD ever brings on thoughts of harming yourself, treat this as urgent. Contact your GP, call NHS 111, or speak to Samaritans free, any time, on 116 123. In an emergency, call 999.