In brief. ADHD and autism are distinct neurodevelopmental conditions that overlap heavily: both affect executive function, sensory processing and social life, and between a third and a half of people with one meet criteria for the other. Until 2013 the diagnostic manual did not allow both to be diagnosed together, so many adults were given one label when they had two. Knowing which you have, or that you have both, changes what helps.
Core differences
| Area | ADHD | Autism |
|---|---|---|
| Attention | Hard to regulate; drawn to novelty and interest; distractible | Often deep and sustained on preferred topics; hard to shift |
| Routine | Bored by it, struggles to keep it, but functions better with it | Needs it; distressed when it changes |
| Social life | Understands the rules but breaks them impulsively (interrupting, oversharing) | Differences in intuiting the rules; may learn them explicitly |
| Sensory | Seeks stimulation; sensitivity tied to attention | Stable sensitivity or under-sensitivity across settings |
| Novelty | Craves it | Often finds it stressful |
| Emotion | Fast, reactive, quick to recover | Slower to identify and express; meltdowns and shutdowns under overload |
| Onset | Symptoms before age 12 | Present from early development |
Where they overlap
- Executive dysfunction: planning, organising, initiating, switching.
- Sensory differences and overload.
- Social exhaustion and difficulty in groups.
- Emotional intensity.
- Sleep problems.
- High rates of anxiety and depression.
- Rejection of sameness and difficulty with sameness, in the same person.
Two questions to start
Take the full self-testWHO adult ADHD screener. Scored on your device. A screen is not a diagnosis.
AuDHD: having both
Since DSM-5 (2013) both can be diagnosed together, and the combination is increasingly recognised. People with both often describe internal conflict: craving stimulation and being overwhelmed by it, needing routine and being unable to keep one, wanting people and needing days to recover from them. The ADHD can mask the autism (an ADHD person seems outgoing) and the autism can mask the ADHD (an autistic person seems organised). See AuDHD.
How assessment tells them apart
A developmental history, symptoms across settings, and careful questioning about the why behind behaviours: are you late because you lost track of time or because the transition is unbearable; do you avoid parties because they bore you or because they overload you; do you interrupt because you cannot wait or because you did not read the pause. Standardised measures for each (ASRS, AQ-10, RAADS-R, CAT-Q) help, and a good assessor considers both conditions in every adult presenting with either.
Why it matters
Treatments differ. ADHD often responds to medication; autism does not have a medication. Therapy for ADHD emphasises structure and activation; therapy for autism emphasises predictability, sensory management and reducing masking. Someone with both needs a plan that holds the tension, which is why a diagnosis of one that ignores the other so often gives partial relief.
What Inner Help does
Our finder lists practitioners who state they work with ADHD, autism or both, and our free self-tests cover each. Matching asks about both so the practitioner you see is used to the combination.
Get matched to a therapist.
A short questionnaire, then a practitioner who understands neurodivergence. Per session with your rebate lodged, or a weekly plan.
Frequently asked questions
Can ADHD be mistaken for autism?
Yes, in both directions, particularly in adults who mask. Executive and sensory overlap is the usual cause. Assessment by someone experienced in both is the safeguard.
Is AuDHD an official diagnosis?
No. It is a community term for having both diagnoses. Clinicians write "ADHD and autism spectrum disorder".
Which should I be assessed for first?
Ideally both at once. If choosing, start with the one whose treatment would change your life most; ADHD assessment is generally quicker and cheaper.
Does ADHD medication help autism?
It treats the ADHD component, which in AuDHD often relieves a good deal of daily difficulty. It does not treat autism itself.
Sources and review
Last updated 2026-09-14.