ADHD and OCD: Can You Have Both?

Short answer: Yes, you can have both. OCD is more common in adults with ADHD than in the general population.¹ But how often the two truly occur together is uncertain: reported rates vary widely, and a systematic review cautioned that symptoms caused by OCD may be misdiagnosed as ADHD.² Because the two can look alike, a careful assessment matters, and each condition needs its own treatment.³

What is OCD?

Obsessive-compulsive disorder (OCD) involves obsessions and compulsions:

• Obsessions are unwanted thoughts, images or urges that keep coming to mind and cause distress. Common examples include fear of germs, fear of hurting others, needing things in order, and worry about having forgotten to lock the door or turn off an appliance.⁴
• Compulsions are behaviours or rituals repeated to reduce the anxiety linked to the obsessions — for example, excessive handwashing or cleaning, continually checking taps, locks or light switches, counting, or constantly seeking reassurance.⁴

People with OCD are usually aware that their obsessions and compulsions are irrational and excessive.⁵ OCD affects more than 500,000 people in Australia and usually starts in late childhood or the early teenage years.⁴ People with OCD are also more likely to develop depression or other anxiety conditions, such as panic disorder or social anxiety.⁴ Anxiety can also occur alongside ADHD;⁶ see ADHD and anxiety.

Can you have ADHD and OCD?

Yes. The Australian ADHD Guideline lists OCD among the conditions adults with ADHD may experience at higher rates than the general population, along with substance use disorders, bipolar disorders and some personality disorders.¹ It also advises clinicians that ADHD is more common in adults with any mental health condition,³ so it’s worth considering ADHD in someone with OCD, and OCD in someone with ADHD.

How often do they occur together?

That’s harder to pin down. A 2015 systematic review of the research across the lifespan found that reported rates of ADHD and OCD occurring together are highly inconsistent, and that many studies had weaknesses: very few drew on samples from the general community, rules about who could take part varied a lot, and symptoms may sometimes have been misinterpreted.²

The review also found that:

• genetic evidence for a true link between the two has so far been found only in children;²
• tic disorders may have inflated some estimates of the overlap;²
• in children with OCD, differences in how the brain matures may produce possibly temporary symptoms that resemble ADHD and may be misdiagnosed as ADHD — which could help explain why lower rates of the two together are reported in teenagers and adults.²

In short, you can have both, but some of what looks like ADHD in a person with OCD may turn out to be OCD itself.

Why ADHD and OCD can look alike

Both conditions can affect concentration, organisation and how long everyday tasks take — but usually for different reasons.

In OCD, attention can be taken up by intrusive thoughts and rituals, and obsessions and compulsions may take up many hours of a person’s day.⁵ From the outside, that can look like being distracted, disorganised or always running late. Researchers have cautioned that ADHD-like symptoms caused by OCD may be mistaken for ADHD.²

In ADHD, attention problems are a long-standing pattern that starts in childhood — being easily distracted, putting off tasks that need sustained effort, and starting things without finishing them.⁷

Anxiety adds another layer. Compulsions are carried out to relieve anxiety,⁴ and anxiety on its own can make it hard to concentrate.⁸

ADHD vs OCD: key differences

Researchers describe a “stark contrast” between the two conditions, both in how they show up and in their underlying biology.² These are general differences clinicians consider, not a way to diagnose yourself.

Acting on impulse vs acting on compulsion

ADHD can involve impulsivity: acting without thinking, interrupting and finding it hard to wait.⁷ OCD compulsions work differently. They’re behaviours or rituals repeated to reduce the anxiety caused by obsessions⁴ — less about acting too quickly, and more about feeling you have to do something again and again.

Doubt and checking vs forgetting

Both can leave you wondering whether you locked the door, but in different ways. In OCD, worry about having forgotten to lock a door or turn off an appliance is a common obsession, and continually checking locks, taps or switches is a common compulsion.⁴ In ADHD, the more typical problem is genuinely forgetting things or losing them.⁷

Distress vs boredom

In OCD, the obsessions cause distress and the compulsions are an attempt to relieve it.⁴ ADHD, by contrast, can involve finding boredom hard to cope with and looking for stimulation.⁷

When it started

ADHD symptoms must have been present before age 12,⁷ and OCD usually starts in late childhood or the early teens,⁴ so timing alone doesn’t settle it. That’s one reason a full assessment includes a detailed developmental history.³

Why diagnosis can be tricky

The Australian ADHD Guideline warns clinicians that a co-occurring condition can lead to ADHD being missed — or the other condition being missed when ADHD symptoms are present.⁹ There’s no single test for OCD: a doctor makes the diagnosis based on your behaviours, thoughts, feelings, level of distress and how much it affects your life, and rules out other conditions.⁴ An ADHD assessment likewise relies on a detailed interview, your developmental, mental health and medical history, reports from people who know you, and checks for other causes of your symptoms.³

Online symptom lists can’t make this distinction for you. If you recognise yourself in both conditions, tell your GP so each one can be looked at properly. For a fuller picture of how ADHD shows up, see ADHD symptoms in adults.

Treating ADHD and OCD

Each condition is treated in its own right: the Australian ADHD Guideline recommends that co-occurring conditions are treated with the best-practice approach for that condition, with the way treatment is delivered adjusted to account for ADHD symptoms.³ When conditions occur together, guidelines generally suggest treating the most impairing one first.¹⁰

Treatment for OCD

Treatment for OCD includes cognitive behaviour therapy (CBT) guided by a mental health professional, and exposure and response prevention (ERP), in which you list situations from least to most anxiety-provoking and gradually work through them while cutting back on compulsions.⁴ Antidepressant medicines are also used to treat OCD in Australia, and your GP may refer you to a psychologist, psychiatrist or occupational therapist.⁴

Treatment for ADHD

ADHD treatment can include education, psychological support, coaching, practical strategies and medication.⁶ When you have both conditions, your care may involve more than one health professional, so make sure each one knows about the other condition and any medicines you take. Don’t start, stop or change a medicine without talking to your doctor or pharmacist.

When to get help

See your GP if intrusive thoughts, rituals, or problems with attention and organisation are taking up your time or getting in the way of work, study or relationships. Your GP can help work out what’s going on and arrange the right assessment or referral.

For 24-hour support, call Lifeline on 13 11 14 or Beyond Blue on 1300 22 4636. If you or someone else is in crisis and needs help now, call 000.¹¹

Frequently asked questions

Can you have ADHD and OCD at the same time?

Yes. OCD is more common in adults with ADHD than in the general population. But researchers have cautioned that some studies may have overestimated how often the two occur together.

Can OCD be mistaken for ADHD?

It can. OCD can cause problems that look like ADHD, and a 2015 review suggested these may sometimes be misdiagnosed as ADHD.

What’s the difference between ADHD and OCD?

ADHD involves long-standing problems with attention, hyperactivity or impulsivity that begin in childhood. OCD involves unwanted, distressing thoughts and repeated behaviours or rituals carried out to ease the anxiety those thoughts cause.

Is constantly checking things a sign of ADHD or OCD?

Repeatedly checking locks, taps or switches because of worry is a common OCD compulsion. In ADHD, the more typical problem is genuinely forgetting or losing things. Only a proper assessment can tell what’s going on.

How is OCD treated?

Treatment includes cognitive behaviour therapy, exposure and response prevention, and sometimes antidepressant medicines. If you also have ADHD, each condition is treated in its own right.

Next steps

Read ADHD and anxiety and how to get an ADHD assessment in Australia, or start with the free ADHD self-assessment.

This article is general information only and is not medical advice. Only a qualified health professional can diagnose ADHD. ADHD GP is a private telehealth clinic staffed by AHPRA-registered Australian GPs.

Book your ADHD assessment

References

1. Australian ADHD Professionals Association. About ADHD (Australian ADHD Guideline). 2022. adhdguideline.aadpa.com.au — ADHD affects 6–10% of Australian children and 2–6% of adults; heritability 70–80%; symptoms begin before 12 though diagnosis may come later; 60–86% persist into adulthood; inattentive presentation most prevalent; up to 80% of adults have another mental health condition; describes executive-function, brain-maturation and dopamine differences.
2. Abramovitch A, Dar R, Mittelman A, et al. Comorbidity Between Attention Deficit/Hyperactivity Disorder and Obsessive-Compulsive Disorder Across the Lifespan: A Systematic and Critical Review. Harvard Review of Psychiatry. 2015. PubMed PMID 26052877 — Reported ADHD–OCD co-occurrence rates are highly inconsistent and studies have methodological problems; ADHD-like symptoms caused by OCD may be misdiagnosed as ADHD, so the overlap may be overestimated.
3. Australian ADHD Professionals Association. Australian ADHD Guideline — summary of recommendations. 2022. adhdguideline.aadpa.com.au — Medication is the most effective treatment for core symptoms, with non-medication treatments adding support (3.1.1); diagnosing clinicians should be registered and trained in ADHD assessment (2.1.1); the diagnosis must be confirmed before starting medication (5.1.2); CBT should be offered to adults (4.2.11); stimulants are first-line for impairing adult ADHD, with heart rate, blood pressure, weight, sleep, mood and anxiety monitored during titration; co-occurring conditions get best-practice treatment.
4. healthdirect (Australian Government). Obsessive-compulsive disorder (OCD) — symptoms and treatment. 2024. www.healthdirect.gov.au — OCD involves distressing obsessions and repeated compulsions such as checking; it affects over 500,000 Australians, usually starts in late childhood or early teens, and is treated with CBT, ERP and antidepressants.
5. Better Health Channel (Victorian Government). Obsessive compulsive disorder. 2022. www.betterhealth.vic.gov.au — People with OCD are usually aware that their obsessions and compulsions are irrational and excessive; obsessions and compulsions may take up many hours of a person’s day.
6. Better Health Channel (Victorian Government). ADHD — adults. 2026. www.betterhealth.vic.gov.au — About 7 in 10 children continue to experience ADHD symptoms as adults; treatment can include education, psychological support, coaching, practical strategies and medication.
7. healthdirect (Australian Government). Attention deficit hyperactivity disorder (ADHD). 2025. www.healthdirect.gov.au — ADHD is a neurodevelopmental condition that begins in early childhood; around 1 in 20 people in Australia has ADHD; it is partly genetic; an adult diagnosis requires evidence that symptoms began in childhood; learning difficulties can occur alongside it.
8. healthdirect (Australian Government). Anxiety. 2024. www.healthdirect.gov.au — Anxiety disorders are the most common mental health conditions in Australia, affecting 1 in 4 at some stage; symptoms include difficulty concentrating; CBT and self-care such as exercise and less caffeine can help.
9. Australian ADHD Professionals Association. Australian ADHD Guideline — Chapter 2: diagnosis. 2022. adhdguideline.aadpa.com.au — Clinicians should know which conditions commonly co-occur with ADHD, as a co-occurring condition may result in a missed ADHD diagnosis, or a missed co-occurring condition when ADHD symptoms are present.
10. Katzman MA, Bilkey TS, Chokka PR, et al. Adult ADHD and comorbid disorders: clinical implications of a dimensional approach. BMC Psychiatry. 2017. PubMed PMID 28830387 — Adult ADHD often co-occurs with mood and anxiety disorders, with strong familial and neurobiological links; overlapping symptoms complicate diagnosis; guidelines advise treating the most impairing condition first.
11. healthdirect (Australian Government). Mental health helplines. 2025. www.healthdirect.gov.au — Lifeline (13 11 14) offers 24-hour crisis support and Beyond Blue (1300 22 4636) is available 24/7; if someone is in crisis and needs help now, call triple zero (000).

Sources were last checked on 5 October 2026. See all sources used on this site on our Sources page.