ADHD and OCD together in adults

ADHD and obsessive-compulsive disorder (OCD) sound like opposites: one associated with acting without thinking, the other with rigid rituals and caution. Yet some adults recognize themselves in both, and the internet often says the two go together. The research picture is more mixed than that, especially for adults. This page explains what the studies show, why OCD can look like ADHD, and how evaluation and treatment work when both may be present.

If your main question is which one fits your symptoms, see ADHD or OCD: how they differ. This page is about the possibility of having both.

What each condition is

The National Institute of Mental Health (NIMH) describes OCD as uncontrollable, recurring thoughts (obsessions), repetitive behaviors (compulsions), or both, that take up time and cause distress or interfere with daily life. Symptoms usually begin between late childhood and young adulthood, and most people with OCD are diagnosed as young adults.

ADHD, also as NIMH describes it, is a persistent pattern of inattention and/or hyperactivity and impulsivity that causes problems in at least two areas of life, with symptoms starting before age 12.

A 2015 review in the Harvard Review of Psychiatry sets out how differently the two usually look:

The review's authors describe the two as sitting at opposite ends of an impulsive-compulsive continuum, which is part of why they question how often genuine co-occurrence happens in adults.

How often they occur together

The honest answer is that nobody knows precisely.

• Reported rates vary enormously. The 2015 review looked at 48 studies and found co-occurrence rates from 0% to 60%. The unweighted average was about 19% in youth samples and about 9% in adult samples.
• A national survey found little difference. In the US National Comorbidity Survey Replication, 2.7% of adults with ADHD had OCD in the past year, compared with 1.3% of adults without ADHD. That gap was not statistically significant, unlike the large gaps the same survey found for anxiety, mood and substance use disorders.
• The link is clearer in children. A 2014 review in ADHD Attention Deficit and Hyperactivity Disorders describes high comorbidity especially of ADHD in children with OCD, and notes that both conditions involve some of the same executive functions. The 2015 review adds that genetic backing for the overlap exists only for the childhood form, and that tic disorders may inflate some reported rates.

Why OCD can look like ADHD

The 2015 review raises a specific concern for adults. Obsessive thoughts can overload a person's mental resources, leading to problems that resemble ADHD criteria: trouble concentrating, restlessness, avoiding tasks that need mental effort, and distraction. Someone checking whether the stove is off, again, is not attending to the meeting. The authors encourage clinicians to consider that ADHD-like symptoms caused by OCD may be misdiagnosed as ADHD.

NIMH adds another reason OCD gets missed or mislabeled: people may not mention their obsessions and compulsions out of fear of judgment, and worry, anxiety and low mood can look like other conditions.

NIMH lists common obsessions, such as fear of germs or contamination, fear of losing or misplacing something, and a need for things to be symmetrical or in perfect order, and common compulsions, such as excessive cleaning, arranging items precisely, repeated checking, counting, or silently repeating words. NIMH also notes that everyone double-checks things sometimes; people with OCD generally cannot control these thoughts or behaviors, spend more than an hour a day on them, and get no pleasure from the rituals beyond brief relief.

For an evaluation, that means two things. First, the history matters: ADHD symptoms should go back to childhood, while OCD often starts later. Second, it helps to describe intrusive thoughts and rituals openly, even if they feel embarrassing. A clinician cannot sort out what is never mentioned.

How the evaluation handles both

NICE guideline NG87 says an ADHD diagnosis should rest on a full clinical and psychosocial assessment, including a psychiatric history, and that the diagnostic process should include assessment of coexisting conditions. Dr. Shershow's adult ADHD evaluation covers current symptoms, childhood, school and work history, health, sleep and substances, and other explanations for symptoms, either instead of ADHD or alongside it, and ends with what it found and the treatment options that fit. OCD is considered as part of that evaluation; the practice does not offer therapy or standalone OCD treatment.

Preparation tips are in how to prepare for an adult ADHD evaluation.

What treatment looks like when both are present

OCD has its own established treatments. NIMH describes cognitive behavioral therapy, and in particular exposure and response prevention (ERP), as effective for OCD, and lists serotonin-targeting antidepressants such as SSRIs as the main medications. NIMH notes that these medications can take 8 to 12 weeks to start helping. That therapy comes from a therapist or psychologist trained in ERP, not from an ADHD medication visit.

ADHD treatment is adjusted carefully. NICE recommendation 1.7.28 lists anxiety disorders, including OCD, among the conditions that call for slower dose adjustment and more frequent monitoring of ADHD medication. The 2015 review cautions that stimulants may significantly worsen OCD symptoms in some cases, which is one more reason to go slowly and report changes in obsessions or rituals promptly.

Order of treatment. Canadian CADDRA guidance, as summarized in a 2017 BMC Psychiatry review, advises treating the most impairing disorder first when ADHD and an anxiety disorder occur together. Applied here, a person whose rituals consume hours a day may need OCD treatment underway before ADHD medication is started or adjusted. That decision belongs to the patient and clinicians after a full evaluation.

For more on medication choices, see how doctors choose an ADHD medication and ADHD medication and anxiety. Because OCD and anxiety so often travel together, ADHD and anxiety together may also help.

When to talk to a clinician

If intrusive thoughts or rituals take up a lot of your day, talk with a health care provider; NIMH recommends that as the first step, and OCD treatment helps many people. If attention, organization and impulsivity problems date back to childhood, an ADHD evaluation can look at that question too. The adult ADHD self-test is a screener that can help you describe attention symptoms; it is not a diagnosis. To arrange an ADHD evaluation, see ADHD testing in NYC or ADHD testing in New Jersey, or call the office.

If you are having thoughts of harming yourself, call or text 988 to reach the Suicide and Crisis Lifeline, or call 911 in an emergency.