OCD, Autism, and ADHD: Why They Co-Occur and How to Get the Right Diagnosis and Treatment
- Kiesa Kelly
- 22 hours ago
- 10 min read
If you live with OCD and ADHD, or you suspect you do, you may have noticed something else in the mix: sensory sensitivities, a strong need for sameness, social fatigue, or lifelong differences in communication and interests. Many people start wondering about OCD and autism, especially adults who have spent years masking.
When several neurodevelopmental and anxiety-related patterns overlap, the goal is not to sort you into a single box. The goal is to understand what is driving distress, what is simply part of your neurotype, and what kind of support will actually help.
In this article, you'll learn:
Why OCD, ADHD, and autism traits often overlap in real life
What research suggests about co-occurrence and why prevalence numbers differ
How to tell OCD compulsions from autistic routines and sameness needs
How ADHD affects rituals, attention, and follow-through
How neurodivergent OCD treatment can adapt ERP without coercion
💡 Key takeaway: Overlap is common, but the right care depends on identifying the function of behaviors, not just how they look.
Why these diagnoses often travel together
Shared and overlapping circuits: frontostriatal loops, inhibition, habit learning
OCD and ADHD are often discussed as opposites, but both involve brain networks that support inhibition, attention allocation, and habit learning. In simplified terms, OCD is frequently associated with over-engagement of threat-monitoring and habit loops, while ADHD is often associated with under-engagement or inefficient engagement of networks involved in sustained attention and inhibition. These patterns can coexist in the same person and can shift across development, stress, sleep, and medication changes.[1-3]
Why does that matter clinically? Because when inhibition, working memory, or cognitive flexibility are taxed, the brain tends to default to what is familiar. For OCD, that can mean falling back into rituals, checking, or mental review. For autism, that can mean leaning harder on routines or predictable environments. For ADHD, it can mean difficulty holding steps in mind long enough to interrupt a ritual or complete an exposure plan.[2,3]
Overlap is not the same condition: why differential diagnosis still matters
Similar looking behaviors can come from different internal experiences. A person might repeat a phrase because it feels satisfying and regulating, or because they fear something terrible will happen if they do not. A person might avoid a store because it is sensory overload, or because they fear contamination, harming someone, or making a moral mistake.
Accurate differential diagnosis protects you from two common problems:
Treating autism traits like symptoms that must be eliminated
Missing OCD because routines or rigidity are assumed to be “just autism”
A good assessment listens for the meaning of a behavior, its emotional tone, and what happens if you resist it.[4]
🔎 Key takeaway: A behavior can look identical on the outside and be completely different on the inside.
What the research says and why numbers vary
Researchers have consistently documented overlap between OCD, ADHD, and autism, but the exact rates vary a lot depending on age, referral setting, how diagnoses are assessed, and whether a study measures full diagnostic criteria versus trait cutoffs.
In one large clinical youth cohort, about 25% of youth with OCD had co-occurring ASD
In a large clinical youth sample, investigators found that roughly one in four young people with OCD had a co-occurring autism spectrum diagnosis.[5] Studies like this tend to produce higher rates than community surveys because clinics see more severe, complex, or treatment-resistant cases.
In an adult OCD outpatient sample, about 47% scored above an autistic-traits cutoff and about 27.8% met ASD criteria
In an adult OCD outpatient sample in the UK, nearly half of participants scored above an autistic-traits cutoff, and more than a quarter met ASD criteria based on clinical interview.[6] That does not mean “most OCD is autism.” It does highlight that adult OCD autism traits can be missed for years, especially in people who have learned to mask or compensate.
ADHD–OCD co-occurrence varies by age and sample
A systematic review noted that reported ADHD–OCD co-occurrence rates are highly inconsistent across studies, with wide ranges in pediatric samples and generally lower rates in adult samples.[2] Methodology matters: some studies exclude ADHD, some exclude tic disorders, and some ADHD-like symptoms may reflect OCD-driven distraction (for example, “I can’t focus because I’m stuck in mental checking”).[2]
🧭 Key takeaway: Prevalence numbers are useful context, not a personal diagnosis. Your treatment plan should be based on your actual symptom function.
OCD compulsions vs autistic routines and sameness needs
One of the most important clinical tasks is differentiating autism and OCD symptoms that look similar. Here are two practical ways clinicians and clients often sort it out.
Function test: reducing threat or anxiety vs increasing comfort, joy, predictability
Ask, “What is this behavior doing for me?”
OCD compulsions are usually aimed at reducing perceived threat, uncertainty, or responsibility. The relief often feels temporary, and the fear returns quickly.
Autistic routines and sameness needs are often about predictability, sensory regulation, or enjoyment. They can be flexible in the right conditions, especially when the environment is supportive.
A concrete example:
Someone washes their hands repeatedly because they fear contamination, harming a loved one, or being morally “bad.” That is more consistent with OCD.
Someone washes their hands once in a specific way because the sensation feels regulating, or because the transition into bedtime is easier when the routine is predictable. That may be an autistic routine.
Both can coexist. Some autistic people also develop OCD themes about contamination, symmetry, morality, or harm, and the compulsions may layer on top of baseline routines.[4]
Ego-dystonic vs ego-syntonic with nuance and masking considerations
OCD is typically described as ego-dystonic: the thoughts and urges feel unwanted, intrusive, or “not me.” Autism-related routines are more often ego-syntonic: “This is how I function best.” But there is nuance. Some autistic people feel shame about their needs because of years of criticism, and that can make helpful routines feel “wrong.” Meanwhile, some OCD rituals can start to feel automatic or “just what I do,” especially when someone has lived with untreated OCD for a long time.[4]
🧩 Key takeaway: When in doubt, follow the emotion. OCD tends to come with threat and urgency; routines tend to come with regulation and preference.
How OCD and ADHD interact
The phrase ADHD OCD comorbidity can sound abstract until you see how it affects day-to-day life. ADHD does not “cause” OCD, but it can change how OCD shows up and how treatment needs to be structured.
Impulsivity vs compulsivity: attention and working memory effects on rituals
OCD compulsions are often driven by an urge to neutralize or prevent a feared outcome. ADHD can add:
More difficulty pausing between trigger and response
More “starting over” because steps are forgotten mid-ritual
More time lost to distractions that then restart a checking or reassurance loop
For some people, the result is a frustrating cycle: “I tried to stop the ritual, but I lost track, and now I have to do it again to be sure.” This is one reason an assessment should examine how much of the impairment comes from OCD severity versus executive function strain.[2,3]
Treatment pacing: executive supports, reminders, smaller steps
When ADHD is present, ERP often works best with extra scaffolding. Examples include:
Shorter, more frequent exposure practice blocks
Visual checklists and simple “if-then” plans
External reminders for homework and scheduled worry windows
Breaking response prevention into the smallest doable step
If you benefit from executive supports in other areas of life, it is reasonable to bring that same approach into therapy. For additional support, ScienceWorks offers executive function coaching that can complement OCD work.
✅ Key takeaway: If ERP homework keeps slipping, the solution is often structure and supports, not more self-criticism.
Treatment that fits for OCD and ADHD: neurodiversity-affirming ERP and adaptations
ERP is a core component of evidence-based treatment for OCD, and major guidelines recommend CBT with ERP as a first-line option.[7,8] Many autistic people and AuDHD adults can benefit from ERP too, especially when it is adapted to their learning style, sensory profile, and consent needs.[9-11]
If you are looking for an OCD therapist in Tennessee or online therapy in Tennessee for OCD, it can help to ask directly about experience with neurodivergent OCD treatment.
Values-based hierarchies, collaborative choice, sensory accommodations
A neurodiversity-affirming approach keeps the target clear: we treat OCD compulsions and avoidance, not autism. Adaptations often include:
Collaborative hierarchy building that connects exposures to your values and real-life goals
Concrete language and visual supports for SUDS ratings or progress tracking
Sensory planning (lighting, background noise, breaks, fidgets) so ERP is not derailed by overload
Flexible pacing, sometimes with shorter sessions or more processing time
These ideas align with practical recommendations from OCD specialty organizations for adapting ERP with autistic clients.[9,10]
A practical example:
If your trigger is “maybe I offended someone,” an exposure might be sending a short message without rereading it ten times.
If the sensory load of the phone screen is part of the problem, you might do the exposure on a computer with adjusted brightness, then generalize later.
Response prevention that targets rumination and reassurance without coercion
For many people with OCD and ADHD, the “compulsion” is not just a visible behavior. It can be mental reviewing, rumination, reassurance seeking, or repeated online searching. Response prevention can target those processes in a way that still respects autonomy:
Agreeing on what counts as reassurance versus normal support
Using “I can handle uncertainty” scripts without forcing a particular emotional state
Practicing self-compassionate disengagement from rumination (for example, noticing the urge to analyze and returning to your next valued action)
Misconceptions worth correcting:
“ERP is exposure that floods you.” Well-delivered ERP is gradual, collaborative, and planned.[7,8]
“ERP cannot work for autistic people.” Research and clinical guidance support adapted ERP approaches, although engagement may require more structure and accommodations.[9-11]
“If you have ADHD, you cannot do ERP.” ADHD often means the plan needs more scaffolding, not that treatment is impossible.[2,3]
🌿 Key takeaway: Good ERP is effective and respectful. Adaptations are not “watering it down,” they are making it accessible.
Assessment and care coordination for Tennessee telehealth
When multiple conditions overlap, a thoughtful assessment can reduce years of second-guessing. It can also prevent mislabeling autistic needs as compulsions or missing OCD because routines are assumed to be “just personality.”
If you are considering evaluation, ScienceWorks offers psychological assessments and therapy services. Screening tools can also help you decide what questions to bring to your clinician, such as the AQ-10 autism screener and the ASRS ADHD screener. These do not diagnose, but they can guide a conversation.
What to ask: differential diagnosis plan plus co-occurring sleep and trauma screening
Consider asking your clinician:
How will you differentiate OCD compulsions from autistic routines or sensory regulation?
What measures will you use (for example, structured interviews or validated rating scales)?
How will you assess common co-occurring issues like sleep problems, trauma history, or depression, which can worsen both OCD and executive functioning?
Coordinating therapy, psychiatry, and primary care when needed
Some people benefit from a combined plan: ERP-focused therapy plus medication management (often SSRIs for OCD, and ADHD medications when appropriate), alongside primary care support for sleep, thyroid issues, iron deficiency, or other medical factors that can influence anxiety and attention.[7]
If you are in Tennessee and prefer telehealth, coordinated care can happen remotely with clear communication between providers. If you want help getting started, you can contact ScienceWorks to ask about evaluation, therapy, and fit.
🗺️ Key takeaway: The best plan often treats the OCD directly while supporting executive function and sensory regulation.
Conclusion
OCD, autism, and ADHD can co-occur because they share overlapping brain systems and because real life is complex. The key clinical question is not “Which label wins?” It is “What is causing distress and what supports will help me function and feel more like myself?”
If you see yourself in the overlap, you deserve care that is both evidence-based and neurodiversity-affirming. That means accurate differential diagnosis, thoughtful pacing, and ERP that targets OCD without trying to erase autistic needs.
Next step options:
If you want diagnostic clarity, consider a comprehensive evaluation through psychological assessments.
If you are ready for treatment, explore OCD therapy and ERP support, including telehealth options.
If ADHD-related planning and follow-through are getting in the way, consider executive function coaching alongside therapy.
About the Author
Kiesa Kelly, PhD, is a licensed psychologist and the owner of ScienceWorks Behavioral Healthcare. She earned her PhD in Clinical Psychology with a concentration in Neuropsychology from Rosalind Franklin University of Medicine and Science and completed clinical practica, internship, and an NIH-funded postdoctoral fellowship at multiple medical centers and universities.
Her clinical work focuses on psychological assessment and evidence-based treatment, including care for anxiety and neurodevelopmental concerns. ScienceWorks provides services in Tennessee and offers telehealth in multiple states.
References
Cabarkapa S, King JA, Dowling N, Ng CH. Co-Morbid Obsessive-Compulsive Disorder and Attention Deficit Hyperactivity Disorder: Neurobiological Commonalities and Treatment Implications. Front Psychiatry. 2019;10:557. https://doi.org/10.3389/fpsyt.2019.00557 (PubMed: https://pubmed.ncbi.nlm.nih.gov/31456703/; Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC6700219/)
Abramovitch A, Dar R, Mittelman A, Wilhelm S. Comorbidity Between Attention Deficit/Hyperactivity Disorder and Obsessive-Compulsive Disorder Across the Lifespan: A Systematic and Critical Review. Harv Rev Psychiatry. 2015;23(4):245–262. https://doi.org/10.1097/HRP.0000000000000050 (PubMed: https://pubmed.ncbi.nlm.nih.gov/26052877/; Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC4495876/)
Vaidya CJ, Stollstorff M. Cognitive neuroscience of Attention Deficit Hyperactivity Disorder: current status and working hypotheses. Dev Disabil Res Rev. 2008;14(4):261–267. https://doi.org/10.1002/ddrr.40 (PubMed: https://pubmed.ncbi.nlm.nih.gov/19072750/; Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC4437560/)
Paula-Pérez I. Differential diagnosis between obsessive compulsive disorder and restrictive and repetitive behavioural patterns, activities and interests in autism spectrum disorders. Rev Psiquiatr Salud Ment. 2013;6(4):178–186. https://doi.org/10.1016/j.rpsm.2012.07.005 (PubMed: https://pubmed.ncbi.nlm.nih.gov/23084795/)
Martin AF, Jassi A, Cullen AE, et al. Co-occurring obsessive-compulsive disorder and autism spectrum disorder in young people: prevalence, clinical characteristics and outcomes. Eur Child Adolesc Psychiatry. 2020;29(11):1603–1611. https://doi.org/10.1007/s00787-020-01478-8 (PubMed: https://pubmed.ncbi.nlm.nih.gov/32008168/; Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC7595977/)
Wikramanayake WNM, Mandy W, Shahper S, et al. Autism spectrum disorders in adult outpatients with obsessive compulsive disorder in the UK. Int J Psychiatry Clin Pract. 2018;22(1):54–62. https://doi.org/10.1080/13651501.2017.1354029 (PubMed: https://pubmed.ncbi.nlm.nih.gov/28705096/)
Reddy YCJ, Sundar AS, Narayanaswamy JC, Math SB. Clinical practice guidelines for obsessive-compulsive disorder. Indian J Psychiatry. 2017;59(Suppl 1):S74–S90. https://doi.org/10.4103/0019-5545.196976 (PubMed: https://pubmed.ncbi.nlm.nih.gov/28216787/; Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC5310107/)
National Institute for Health and Care Excellence (NICE). Obsessive-compulsive disorder and body dysmorphic disorder: treatment (CG31). (Last reviewed: 11 July 2024.) https://www.nice.org.uk/guidance/cg31 (PDF: https://www.ncbi.nlm.nih.gov/books/NBK56457/pdf/)
International OCD Foundation (IOCDF). Treatment for Autism and OCD. https://iocdf.org/autism/treatment/
International OCD Foundation (IOCDF). ERP Adaptations for Our Autistic Members: 20 Things to Know. (PDF, 2023.) https://iocdf.org/wp-content/uploads/2023/07/BLOG_-ASD_OCD-How-To-Adapt-ERP.pdf
Flygare O, Andersson E, Ringberg H, et al. Adapted cognitive behavior therapy for obsessive–compulsive disorder with co-occurring autism spectrum disorder: a clinical effectiveness study. Autism. 2020;24(1):190–199. https://doi.org/10.1177/1362361319856974 (PubMed: https://pubmed.ncbi.nlm.nih.gov/31187645/)
Lehmkuhl HD, Storch EA, Bodfish JW, Geffken GR. Brief report: exposure and response prevention for obsessive compulsive disorder in a 12-year-old with autism. J Autism Dev Disord. 2008;38(5):977–981. https://doi.org/10.1007/s10803-007-0457-2 (PubMed: https://pubmed.ncbi.nlm.nih.gov/17885801/; Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC3709869/)
Disclaimer: This article is for informational and educational purposes only and is not a substitute for professional diagnosis, treatment, or medical advice. If you are in crisis or think you may harm yourself or someone else, call 988 in the U.S. or go to the nearest emergency room.