Can You Have ADHD and Autism at the Same Time?

By Dr. Tyler Gerdin, PsyD, ABPP | Gerdin Psychological Services

If you’ve spent any time in neurodivergent online communities recently, you’ve probably encountered the term “AuDHD”, shorthand for people who are both autistic and have ADHD. What started as community language has quietly become one of the more clinically important conversations in the field of psychological assessment.

Because yes: ADHD and autism can absolutely occur together. They do so frequently. And when they do, the picture is more complex, and more often missed, than either condition alone.

How Common Is It to Have Both ADHD and Autism?

For a long time, clinicians were taught to pick one. The DSM, prior to its fifth edition, actually precluded diagnosing ADHD and autism simultaneously. That restriction is now gone, removed specifically because the research made it untenable to maintain (Antshel et al., 2019). The conditions co-occur at rates that make dual diagnosis not an exception but an expectation worth actively looking for.

Among autistic people, meta-analyses find that roughly 26 to 40% also meet diagnostic criteria for ADHD (Rong et al., 2021; Lai et al., 2019). Among people with ADHD, studies find clinically significant autistic traits in anywhere from 15 to 64% of individuals, depending on the methods used (Zhong et al., 2024). School-based data suggests about a third of autistic children also have ADHD, and roughly 10% of children with ADHD also have autism (Canals et al., 2024).

Despite these numbers, one study found that only about 16% of school-aged children who met criteria for both conditions had actually been diagnosed with both (Canals et al., 2024). The gap between prevalence and recognition is striking, and it has real consequences for the people living inside that gap.

Why ADHD and Autism Overlap So Frequently

ADHD and autism are distinct conditions with distinct diagnostic criteria, but they share significant underlying terrain. Both involve differences in executive function. Both involve differences in social processing and emotional regulation. Both have strong genetic components, and research increasingly points to overlapping genetic risk factors that help explain why the two so frequently travel together (Antshel et al., 2019; Hours et al., 2022).

Some researchers have proposed that ADHD and autism may represent different expressions of a broader neurodevelopmental continuum, with shared vulnerabilities in self regulation as a common thread (Martin et al., 2026). That framing is still debated, but it reflects a growing recognition that the neat categorical boundaries between these diagnoses are more permeable than the diagnostic manual suggests.

What this means clinically is that the symptoms of each condition don’t simply add together when both are present. They interact with each other in ways that can look quite different from either condition in isolation.

What AuDHD Actually Looks Like in Adults and Teens

When ADHD and autism co-occur, the clinical presentation tends to be more complex and more impairing than either condition alone. Research consistently finds that people with both diagnoses show more severe difficulties in social functioning, executive function, and adaptive behavior, along with higher rates of anxiety, depression, and other co-occurring conditions (Zablotsky et al., 2020; Casseus et al., 2023).

The ADHD component in autistic individuals also tends to skew toward inattentive or combined presentations rather than purely hyperactive, meaning the restlessness and impulsivity that often make ADHD visible may be less prominent, while the attention and executive function difficulties are front and center (Martinez et al., 2024).

Add autism’s masking to the picture, the practiced performance of neurotypicality described in an earlier post, and the combined profile can be genuinely hard to see. An autistic person with ADHD may have spent so much energy learning to appear socially functional that the autism is invisible to a clinician who isn’t probing for it. At the same time, their ADHD may have been the only thing identified, leaving the autistic dimension of their experience unnamed and unaddressed for years.

Both misses matter. Treating only ADHD in someone who is also autistic means their sensory processing differences, their social processing differences, their need for structure and predictability, and the enormous energy cost of navigating a neurotypical world all remain unaccounted for in treatment planning. That’s not a minor gap.

Why ADHD and Autism Are So Hard to Diagnose Together

The symptom overlap between ADHD and autism is real and substantial. Both conditions involve attention difficulties. Both involve executive function challenges. Both can involve emotional dysregulation, sensory sensitivities, and social difficulties. This overlap creates genuine diagnostic complexity, not just for clinicians, but for the people trying to understand themselves.

Several things make accurate dual diagnosis especially difficult. First, clinicians who are trained to think in discrete diagnostic categories may be looking for the “right” answer (ADHD or autism) rather than holding both possibilities simultaneously.

Second, the masking that commonly accompanies autism, particularly in women and high IQ presentations, can make autism invisible in a standard evaluation, leaving only the ADHD consistent symptoms visible.

Third, the tools used in many ADHD evaluations were not designed to screen for autism, and vice versa, meaning a single focused assessment can produce a clean but incomplete answer.

Expert consensus is clear that accurate evaluation for this population requires a comprehensive, multi method approach that explicitly assesses both conditions, gathering developmental history, multiple informant perspectives, behavioral rating data, and cognitive testing, rather than pursuing one diagnosis and stopping (Young et al., 2020; Blanco et al., 2025).

Getting the Full Picture with a Comprehensive Evaluation

If you’ve been diagnosed with ADHD but something still feels unexplained, if social situations exhaust you in a way that goes beyond what ADHD alone would predict, if you’ve always felt fundamentally different from other people in ways you can’t quite articulate, if the description of autism masking resonated with you, it may be worth asking whether the full picture has been assessed.

The same is true in reverse: if you’ve been identified as autistic but struggle significantly with attention, organization, and executive function, ADHD as a co-occurring condition may be contributing in ways that haven’t been addressed.

At Gerdin Psychological Services, complex and overlapping neurodevelopmental presentations are exactly the kind of work we do. A thorough evaluation looks at everything, not just the most obvious presenting concern, so that the picture you walk away with is as accurate and complete as we can make it.

Reach out at drgerdin@gerdinpsych.com or 509-676-4313.

Dr. Tyler Gerdin, PsyD, ABPP is a board certified clinical psychologist in Spokane, Washington, specializing in psychological and neuropsychological assessment for neurodivergent teens and adults.