ADHD or Anxiety? Untangling Two Conditions That Love to Impersonate Each Other
You forgot the appointment again. Was that ADHD, or were you so anxious about getting it wrong that you avoided opening your inbox until it was too late?
If you can't answer that about yourself, or about a client sitting across from you, you're not missing something obvious — you're running into one of the more genuinely confusing overlaps in mental health. These two conditions share symptoms, share brain chemistry, and can each quietly cause the other. Below is how to actually tell them apart, and what the research says about why they get so tangled up.
It's more common than you'd think
Roughly 47% of adults with ADHD also meet criteria for an anxiety disorder, according to the National Comorbidity Survey Replication (Kessler et al., 2006). That's not a small subgroup — it's closer to the norm.
And it's not a mild add-on when it shows up together. A 2022 study in the Journal of Psychiatric Research found that adults with both conditions had measurably worse outcomes than adults with ADHD alone, including more suicide attempts and more anger dysregulation. In kids, the overlap runs around 25–30%, and a 2025 Frontiers in Psychiatry review found the rate climbs even higher in women, which tracks with something clinicians see often: anxiety tends to develop after years of unrecognized executive dysfunction, especially in girls whose ADHD was never identified in the first place.
So if you're looking at someone who's anxious and scattered, odds are decent you're looking at both. That doesn't mean they're the same thing, though.
What actually separates them
Strip away the overlapping symptoms and there's one question that does most of the work: what is the worry actually about?
Anxiety, at its core, is a threat-detection system that's running too hot — global, diffuse, often bigger than whatever triggered it. ADHD isn't about fear at all. It's a neurodevelopmental difference in executive function (working memory, inhibition, planning), present since childhood by definition.
Clinicians increasingly split anxiety in ADHD into two categories, and the distinction is more useful in practice than it sounds on paper:
Secondary anxiety is tightly wired to specific ADHD failures. "I'm anxious because I keep missing deadlines" isn't a global fear response — it's a rational reaction to a real, repeating problem.
A primary anxiety disorder sitting on top of ADHD looks different: diffuse, pervasive worry that isn't clearly tethered to any one executive-function trigger.
Both can be true in the same person at the same time, which is part of why a single intake session rarely settles it.
Why they look so alike anyway
Restlessness, trouble concentrating, a mind that won't slow down, sleep that falls apart — that's the symptom list for both conditions, almost interchangeably. Somewhere between 25% and 50% of people with ADHD also have a diagnosable sleep disorder (Wajszilber et al., 2021), and poor sleep on its own can produce anxiety-like and ADHD-like symptoms in someone who started with neither.
The resemblance goes deeper than the surface, too. Both conditions involve dysregulation in dopamine and norepinephrine, and both are linked to differences in prefrontal cortex function — the region that governs inhibition and emotional control. A 2025 study using the NEPSY-II found kids with ADHD were slower at inhibiting automatic responses than kids with anxiety disorders, but anxiety symptoms also changed how well those inhibition tasks were performed. These aren't two conditions that just happen to resemble each other from the outside; they interact at the level of how the brain processes information. There's a genetic thread as well — both run in families, and having one raises the odds of the other independent of any lived experience.
All of that describes two conditions sitting next to each other. What tends to actually happen is closer to a loop.
How one becomes the other
ADHD creates anxiety. Years of missed deadlines, forgotten commitments, and financial or relational chaos aren't just annoying, they're genuinely stressful, and repeatedly so. Anxiety that grows out of a real track record of difficulty isn't irrational — it's earned. Clinicians sometimes call this reactive anxiety, and treating it as a standalone anxiety disorder, without touching the ADHD generating the chaos underneath it, tends to produce results that don't hold.
Anxiety mimics ADHD, too. A mind flooded with worry has less working memory left over for focus, planning, or task initiation — the exact resources ADHD already compromises. Someone whose brain is constantly scanning for threat can end up looking inattentive and disorganized without having any neurodevelopmental difference at all.
And anxiety can hide ADHD completely. This is the piece that gets missed most often, particularly with late-identified and masked presentations, and it happens frequently in women. I know because it happened to me.
For years, my anxiety had a name, a treatment plan, and a story I fully believed. What I didn't understand was that the anxiety was also doing a job — quietly managing, compensating, overworking to keep a brain that processed things differently from ever looking different at all. It wasn't until I started treating the anxiety itself, with therapy and medication, that what had been underneath it the whole time finally had room to surface: ADHD that had been there all along, just never named, because the anxiety had been covering for it so well that nobody, including me, thought to look further.
I'm one of the clients I see this pattern in constantly now. Anxiety that won't fully resolve, until it does, and a lifetime of undiagnosed executive dysfunction surfaces right behind it. - Jordan
I'm also the clinician on the other side of that conversation now, which is a large part of why I don't take the overlap lightly.
Why guessing wrong costs you time
Treat only the anxiety in someone whose anxiety is mostly downstream of unmanaged ADHD, and you'll likely see partial, short-lived improvement, because the untreated executive dysfunction keeps generating fresh material for the anxiety to grab onto. Treat only the ADHD in someone with a genuine comorbid anxiety disorder, and you can leave them more aware of their gaps without the emotional regulation to sit with that awareness. The research is fairly consistent that treating both, deliberately, beats treating either alone.
I didn't know any of this back when my own anxiety was quietly covering for something else. Now I can't unsee it in a session.
The next time it's hard to tell which one you're looking at, in yourself or in the person across from you, the question to come back to is whether the worry is tied to something specific and executive-functioning-shaped, or whether it's everywhere, about everything, all the time. Often, especially in adults and especially in women, the honest answer is both — and untangling which came first usually matters less than treating the whole picture in front of you.
Sources
Kessler, R. C., et al. (2006). National Comorbidity Survey Replication — anxiety and ADHD comorbidity data.
Anxiety disorders in adult ADHD: A frequent comorbidity and a risk factor for externalizing problems. Journal of Psychiatric Research (2022).
The prevalence of psychiatric comorbidities in adult ADHD compared with non-ADHD populations: A systematic literature review. PLOS ONE (2022).
Adult ADHD and comorbid anxiety and depressive disorders: a review of etiology and treatment. Frontiers in Psychiatry (2025).
ADHD Children Take More Time to Inhibit Automatic Responses: A Comparison with Anxiety Disorders Using NEPSY-II (2025).
Wajszilber, D., et al. (2021). Sleep disorders in ADHD.
Krone, B., & Newcorn, J. H. (2015). Comorbidity of ADHD and anxiety disorders: Diagnosis and treatment across the lifespan. In Attention-Deficit Hyperactivity Disorder in Adults and Children. Cambridge University Press.
