Can OCD be mistaken for ADHD?

Yes. Obsessions take up mental attention, so a person with OCD can look distracted or forgetful. Researchers warn that this can lead to an ADHD diagnosis when OCD is the real cause. Treating the OCD first sometimes improves the attention problems.

Can ADHD medication make OCD worse?

It can in some people. Case reports and reviews link stimulants to new or worse obsessive-compulsive symptoms, while other reports show improvement. Prescribers usually monitor OCD symptoms closely when a stimulant starts or the dose changes.

Is ADHD more common in children with OCD than in adults?

Yes, based on current studies. A 2015 review found an average overlap of about 19% in youth samples and about 9% in adult samples. Some childhood attention symptoms tied to OCD may fade with age.

What kind of doctor diagnoses OCD and ADHD together?

A psychiatrist, child and adolescent psychiatrist, or licensed psychologist can assess both. The assessment usually covers symptom history from childhood, school or work function, and screening for tics and anxiety. A clinician with OCD experience helps separate obsession-driven distraction from ADHD.

Can ERP therapy work if I also have ADHD?

ERP can still help, but ADHD may make it harder to stay on task during exposures. Studies show lower OCD treatment response on average when ADHD is present. Some clinicians address attention problems alongside ERP to help skills stick.

Can You Have OCD and ADHD at the Same Time?

The short answer: Yes. OCD and ADHD can be diagnosed in the same person, and it happens most often in children. Reported overlap rates vary a lot, from 0% to 60% across studies, so no single number is reliable. Some attention problems in OCD come from obsessions, not ADHD, which is why a careful evaluation matters.

Can OCD and ADHD really occur together?

They can, although the pairing looks odd at first. The National Institute of Mental Health (NIMH) describes OCD as unwanted, recurring thoughts (obsessions), repetitive behaviors (compulsions), or both. NIMH describes ADHD as a neurodevelopmental disorder marked by inattention, hyperactivity, and impulsivity.

One condition is about too much control and caution. The other is about too little. A 2014 review in Attention Deficit and Hyperactivity Disorders found that both disorders involve partly overlapping executive functions and brain networks. The same circuits may drive compulsive, repetitive behavior in OCD and disinhibited, impulsive behavior in ADHD.

Both conditions also run in families. A 2015 systematic review in the Harvard Review of Psychiatry cites heritability estimates of about 40% for OCD and 70% to 80% for ADHD. The same review notes that genetic support for a true shared link exists only for the childhood form of the combination so far.

How common is it to have both?

The honest answer is that nobody knows the exact rate. The 2015 Harvard Review of Psychiatry review found reported rates of ADHD in people with OCD ranging from 0% to 60%. Key findings from that review:

Setting matters. Large representative community samples found 0% to 10% overlap. Most studies from specialized clinics found 20% to 59%.
Age matters. The unweighted average was about 19% in youth samples and about 9% in adult samples.
Direction matters. Studies of people with ADHD found OCD in only 1% to 13%.
Tics matter. Tic disorders are common with both conditions, and they may inflate the overlap in some samples.

Individual clinic studies show the same spread. A 2022 study of 364 children with OCD in Ankara, Turkey found ADHD in 39.5%. A 2023 study of 93 adults with OCD in Japan estimated lifetime ADHD at 16.1%. The International OCD Foundation (IOCDF) sums up the research as roughly one in five children with OCD, and one in 12 adults.

Why is the diagnosis so tricky?

OCD can make a person look like they have ADHD. Obsessions use up mental attention. In an IOCDF expert article, researchers Amitai Abramovitch and Andrew Mittelman explain that the more intrusive thoughts a person has in a given moment, the fewer resources are left for other tasks.

Their example is a child who sits in class obsessing over a stain on her sleeve. To a teacher, she looks distracted. The real cause is the obsession, not a core attention problem. The 2015 review urges clinicians to consider that ADHD-like symptoms caused by OCD may be misdiagnosed as ADHD.

A 2017 study of 50 young people treated for OCD tested this idea. Youth whose OCD improved most also had the biggest drop in inattentive symptoms. The authors suggest that clinicians may consider treating OCD before targeting inattentive-type ADHD.

A reliable diagnosis usually needs a full history. ADHD symptoms start in childhood and show up across settings. The same review notes that only 25% to 50% of adults with OCD had their OCD start before age 18.

How do OCD and ADHD symptoms differ?

These questions can help separate the two, though only a clinician can make the call:

Why is attention drifting? In OCD, attention is pulled toward a specific fear or ritual. In ADHD, attention drifts in many directions without a feared theme.
Is there impulsivity? The IOCDF article notes that people with OCD are very rarely impulsive and do not usually take risks. Impulsivity is a core ADHD feature.
Are routines rigid or messy? People with OCD can perform precise, repetitive rituals that follow complex rules. People with ADHD often struggle to keep any routine going.
Does it happen everywhere? ADHD symptoms appear across school, home, and work. OCD distraction may spike around triggers.

Anxiety can also cause focus problems, which adds a third possibility. Our guide on OCD vs. anxiety covers that overlap, and anxiety.md covers anxiety disorders in more depth.

How is OCD with ADHD treated?

There are no large randomized trials for people who have both. A 2019 review in Frontiers in Psychiatry concludes that a reasonable approach is to start with the standard treatment for each condition.

For OCD, NIMH lists serotonin-targeting antidepressants and exposure and response prevention (ERP) as core treatments. NIMH notes that these medicines can take 8 to 12 weeks to start working. OCD may also need higher doses than depression. ERP reduces compulsions even in some people who do not respond well to medicine. See our guides on ERP therapy and OCD medication options.

For ADHD, the CDC says stimulants are the best-known and most widely used medicines. About 70% to 80% of children with ADHD have fewer symptoms while taking them. Non-stimulants and behavior therapy are also options.

Stimulants are where care gets careful. The 2019 review reports that some literature links stimulants to worse or new obsessive-compulsive symptoms. The same review cites other evidence that stimulants can improve co-occurring OCD symptoms, partly by helping people learn and use therapy skills. Because results differ, prescribers usually watch OCD symptoms closely when a stimulant is started or changed.

Does having both change the outlook?

Several studies suggest that having both makes treatment harder, though they are small and clinic-based:

In the Japanese adult study, OCD symptoms improved by 16.1% after six months in people with ADHD. They improved by 44.6% in people without ADHD.
A 2020 Australian study of 80 youth found that those with both conditions were less likely to respond to OCD treatment. They also had weaker executive function and more family accommodation.
The Turkish pediatric study linked ADHD with longer treatment, more tic and conduct problems, and more treatment resistance.

The Australian authors suggest these youth may need a stronger initial course of CBT.

The bottom line

You can have OCD and ADHD at the same time, and the pairing is more common in children than adults. Published rates range from 0% to 60%, so treat any single figure with caution. Obsessions can mimic ADHD, so a careful evaluation should come first. When both are present, standard treatments for each are the usual starting point, with close follow-up on OCD symptoms when stimulants are used.

Last updated: September 2026. This article is for informational purposes only and does not constitute medical advice. Talk with a psychiatrist or psychologist before starting, stopping, or combining any OCD or ADHD treatment.