AuDHD: When ADHD and Autism Occur Together
For individuals and families in Australia navigating multiple diagnoses
For a long time, ADHD and autism were treated as mutually exclusive. Clinicians were actually instructed not to diagnose both in the same person, but that has now changed. Research now makes clear that ADHD and autism co-occur at high rates, and understanding how they interact, (a combination increasingly known as AuDHD), is essential for getting support that’s right for you.
This post explains what co-occurrence means, how it presents, why it's so often missed, and what genuinely helpful support looks like when more than one profile is involved.
How Common Is AuDHD?
Studies suggest that between 50 and 70 per cent of autistic people also meet the criteria for ADHD, and a significant proportion of people with ADHD are also autistic. These aren't rare edge cases, they are the norm rather than the exception for many neurodivergent people.
Despite this, many people receive one diagnosis and are left wondering why the support they're offered doesn't quite cover what they're experiencing. The missing piece is often the other profile.
Why Were They Considered Separate for So Long?
Until 2013, when the DSM-5 was published, clinicians were formally instructed to give only one diagnosis if a person met criteria for both. The assumption was that the conditions couldn't genuinely co-exist. Decades of research have since overturned this view, but the legacy of that thinking means many people assessed before 2013 may have received an incomplete picture.
There is also a genuine overlap problem: ADHD and autism share several features, such as: difficulty with attention, emotional dysregulation, sensory sensitivities, and social challenges, which can make it hard to distinguish between them without a thorough, experienced assessment.
How AuDHD Can Present
There is no single presentation, but some common patterns include:
Attention difficulties beyond what autism alone explains — trouble with tasks that aren't intrinsically motivating, even when there's a genuine desire to engage.
Intense emotional dysregulation — quicker escalation and more difficulty returning to baseline than peers experience.
Significant executive function challenges — planning, initiating tasks, managing time, and organising belongings.
Layered sensory needs — sensory sensitivities alongside an ADHD tendency to seek stimulation. These can look contradictory, but both are real and can exist in the same person.
Social difficulties with two sources — autistic differences in social communication, combined with ADHD-related impulsivity that disrupts interactions.
Compounded exhaustion — from masking, managing sensory input, and regulating attention all at once.
Masking and Late Diagnosis
Masking: the conscious or unconscious suppression of neurodivergent traits to fit in, is common for both autistic people and those with ADHD. When both are present, masking can be especially pronounced and especially exhausting.
Many people, particularly women and those assigned female at birth, reach adulthood with neither diagnosis. They may instead have been diagnosed with anxiety, depression, or borderline personality disorder, labels that address surface symptoms but miss the underlying neurological picture. A late diagnosis of ADHD, autism, or both can be genuinely life-changing, not because it changes who someone is, but because it reframes a lifetime of experience and opens the door to support that actually works for them.
Why This Matters for Treatment and Support
Co-occurrence matters practically because support needs differ depending on the combination:
Medication for ADHD can be highly effective, but if autistic sensory sensitivities or anxiety are also present, medication response and side effects may be more complex and require careful monitoring.
Behavioural approaches designed for ADHD alone may be poorly suited to someone who is also autistic, particularly where a PDA (Pathological Demand Avoidance / Persistent Drive for Autonomy) profile is involved, since demand-based strategies can backfire entirely.
Executive function strategies that work for ADHD often need real adaptation for autistic people, who may have a different relationship with routine, predictability, and change.
Therapy approaches need to be neurodiversity-affirming for both profiles, not treating either as something to be trained out of.
The short version: a clinician who understands only one of these profiles is likely to miss important parts of the picture. Assessment and support that takes both seriously isn't a luxury, it's necessary for accurate, useful help.
What to Look For in an Assessment
If you suspect you or your child may have both ADHD and autism, a thorough assessment should:
Explore developmental history in detail, not just current symptoms
Consider how masking might be obscuring the presentation
Assess for both profiles explicitly, rather than stopping at one
Account for co-occurring anxiety, depression, or trauma, which often interact with both
Include your perspective as a parent, partner, or individual, not rely solely on standardised testing
A formal dual diagnosis is not always required to access support. Many therapists will work with the whole picture rather than waiting for a complete diagnostic report, especially given the lengthy assessment waitlists in Australia.
When to Seek an Assessment
You don't need to wait until things reach a crisis point. Consider seeking an assessment or consultation if:
You've always felt "different" and suspect there may be a neurological reason
Your child is struggling at school despite obvious intelligence or effort
Standard parenting or behavioural strategies aren't working
You've received a diagnosis in one area (e.g. anxiety or depression) but feel something is being missed
A family member has been diagnosed and you recognise yourself in their description
What Genuinely Helpful Support Looks Like
If you or someone you care about is neurodivergent, formally diagnosed or not, here's what good psychological support should include:
Neurodiversity-affirming care. A therapist who understands that neurodivergence isn't something to "fix," but a difference that needs the right environment, strategies, and self-understanding to thrive.
Thorough assessment. Exploring the full picture — history, context, co-occurring conditions, and strengths, not just a checklist.
Individualised strategies. Whether it's executive function support for ADHD, sensory strategies for autism, or low-demand parenting approaches for PDA, support should be tailored, not templated.
Family and carer involvement. Neurodivergence affects the whole family system, and therapists who include families in the process tend to see better outcomes.
Trauma-informed practice. Many neurodivergent people carry significant trauma from years of being misunderstood, bullied, or failed by systems. Effective support acknowledges and works with this, not around it.
A Note on Diagnosis in Australia
Formal diagnosis in Australia can be a lengthy and costly process, and waiting lists are long. This is a genuine barrier, and one the mental health community is actively advocating to change.
A formal diagnosis, however, is not always required to access support. Many therapists, including our team at Mind Over Matters, can work with you based on your individual needs, experiences, and goals, even without a formal diagnostic report.
Medicare rebates are available for psychological services under a Mental Health Treatment Plan. Ask your GP for a referral.
Frequently Asked Questions
Can you be diagnosed with both ADHD and autism? Yes. Since the DSM-5 was published in 2013, clinicians have been able to diagnose ADHD and autism in the same person. Before this, guidelines prevented a dual diagnosis, so many older assessments may not reflect the full picture.
What is AuDHD? AuDHD is a commonly used term for the co-occurrence of Attention-Deficit/Hyperactivity Disorder (ADHD) and autism in the same individual. It's not a formal clinical diagnosis in itself, but a way of describing this specific combination of neurodivergent traits.
Is AuDHD more common than people realise? Yes. Research suggests that between 50 and 70 per cent of autistic people also meet the criteria for ADHD, making co-occurrence far more common than the historical "one or the other" model suggested.
Do I need a formal diagnosis to get support? Not necessarily. Many neurodiversity-affirming therapists, including our team, can work with you based on your experiences and goals even before or without a completed diagnostic assessment.
You Deserve Support That Actually Fits
Neurodivergent people are not broken. They are people whose brains work differently and who often flourish when given the right support, environment, and understanding.
At Mind Over Matters, we provide evidence-based, neurodiversity-affirming psychological support for adolescents, adults, couples, and families across Australia, including via telehealth. Whether you're seeking therapy or guidance navigating a diagnosis, we're here to help.
📞 Ready to take the next step? Contact Mind Over Matters to book an initial consultation
Mind Over Matters is an accredited practice providing trauma-informed, evidence-based mental health support across Australia, including via telehealth.