Many adults spend years wondering why life feels harder than it appears to be for other people. They may struggle with organisation, sensory overwhelm, social situations or emotional regulation, yet never fully understand why. Increasingly, people are discovering that the answer may not be autism or ADHD alone, but both.
Can You Have Autism and ADHD?
Yes. It is entirely possible to be both autistic and have Attention Deficit Hyperactivity Disorder (ADHD).
In fact, research suggests that autism and ADHD frequently occur together. Studies estimate that between 50% and 70% of autistic people also meet criteria for ADHD, while many individuals diagnosed with ADHD show significant autistic traits (Antshel & Russo, 2019).
The co-occurrence of autism and ADHD is sometimes referred to within the neurodivergent community as AuDHD, although this is not a formal clinical diagnosis.
Until relatively recently, clinicians were unable to diagnose both conditions simultaneously. However, changes to diagnostic guidance now recognise that autism and ADHD are separate neurodevelopmental conditions that can exist together.
Understanding this overlap is important because the combination can create a unique profile of strengths and challenges that differs from autism or ADHD alone.
What Is the Difference Between Autism and ADHD?
Although autism and ADHD often overlap, they are distinct conditions.
Autism is characterised by differences in:
- Social communication and interaction
- Sensory processing
- Flexible thinking
- Understanding social expectations
- Need for predictability and routine
- Intense interests and passions
ADHD is characterised by differences in:
- Attention regulation
- Executive functioning
- Impulse control
- Organisation and planning
- Working memory
- Activity levels and restlessness
However, many of these characteristics interact in complex ways when a person has both conditions.
What Does AuDHD Look Like in Adults?
No two autistic or ADHD individuals are the same, but adults with both conditions often describe experiencing seemingly contradictory needs.
You might:
Crave routine but struggle to maintain it
Your autistic traits may prefer predictability and structure, whilst ADHD can make it difficult to consistently follow routines, remember tasks or stay organised.
Need organisation but resist schedules
You may recognise that planning helps reduce anxiety, yet find yourself feeling restricted by rigid timetables.
Have intense interests but become distracted
Many autistic people develop deep interests and expertise in particular topics. ADHD can create challenges with sustaining attention unless an activity is highly engaging.
Experience sensory sensitivities and restlessness
You may be overwhelmed by noise, crowds or bright lights but also have a strong need for movement, fidgeting or sensory stimulation.
Feel socially exhausted but seek novelty
Some adults find social interaction draining while simultaneously craving connection, excitement and new experiences.
Experience frequent burnout
The effort involved in managing both autism and ADHD characteristics can be exhausting, especially when people are trying to meet expectations that do not match their natural ways of thinking and processing information.
Differences between autism and ADHD
Typically, an autistic person tends to crave sameness, familiarity and routine and becomes anxious, unsettled or overwhelmed when things change or do not go to plan. An individual with ADHD tends to seek and enjoy stimulation, spontaneity and new experiences, becoming bored and restless when it comes to familiarity and routine.
In general, the characteristics of autism and ADHD differ in a few key areas:
| Autism | ADHD | |
| Social interest | Avoids social interaction or becomes anxious about social interaction; prefers to interact with a few familiar people | Seeks novel social interaction; can become bored with familiar or predictable people |
| Social interaction | Makes social mistakes due to misunderstanding social expectations | Makes social mistakes due to impulsivity or inattention |
| Interests | Longer-term intense interests in a particular subject and topic | Short-term hyperfixation on particular subjects or topics |
| Routine | Prefers routine and sameness, struggles with new experiences and the unfamiliar | Becomes bored with routine and mundane activities, seeks novel, stimulating activities |
| Plans | Likes to know and understand the plan for the day or weeks ahead, struggles when not sure about what is happening when | Focused on the here and now, seeks short-term gratification over longer-term plans |
Of course, every person is different, as is the way that their neurological differences impact them.
Why Are Autism and ADHD Often Missed Until Adulthood?
Many adults receive a diagnosis in their 30s, 40s, 50s or later.
Research suggests this is particularly common among individuals who:
- Were academically successful
- Developed effective masking or compensation strategies
- Were described as shy, anxious or sensitive
- Internalised difficulties rather than displaying disruptive behaviour
- Grew up when awareness of autism and ADHD was lower
- Were repeatedly treated for anxiety, depression or burnout without exploring underlying neurodevelopmental differences
Women and girls have historically been underdiagnosed due to diagnostic frameworks being largely developed using predominantly male samples. Emerging evidence suggests that many autistic and ADHD women remain unidentified into adulthood.
For some adults, becoming a parent, starting a demanding career, experiencing workplace stress or supporting a neurodivergent child can trigger a period of reflection that leads them to seek assessment themselves.
Masking, camouflaging and exhaustion
It is common for those with autism and ADHD to be acutely aware of their differences and seek to hide them through masking and camouflaging behaviours.
These behaviours can leave autistic people, ADHDers and AuDHDers with short- or long-term burnout, which impacts daily living further.
Signs You May Have Both Autism and ADHD
While only a comprehensive assessment can determine whether you meet diagnostic criteria, some common signs include:
- Lifelong difficulties with organisation and time management
- Social interactions that feel effortful or confusing
- Sensory sensitivities
- Emotional dysregulation
- Frequent procrastination
- Difficulty switching between tasks
- Hyperfocus on interests
- Feeling overwhelmed by change
- Forgetfulness
- Strong need for routines
- Difficulty maintaining routines
- Repeated episodes of exhaustion or burnout
- A history of feeling “different” from peers
Many adults report feeling as though they never fully fitted into expectations despite working incredibly hard to do so.
The Mental Health Impact of Undiagnosed Autism and ADHD
Research consistently shows that autistic and ADHD adults experience higher rates of mental health difficulties than the general population.
Undiagnosed individuals may experience:
- Anxiety
- Depression
- Low self-esteem
- Chronic stress
- Social isolation
- Workplace difficulties
- Relationship challenges
- Repeated burnout
Without an explanation for their experiences, many people develop a belief that they are lazy, disorganised, over-sensitive or failing in some way.
Receiving an accurate diagnosis can help replace self-criticism with understanding and self-compassion.
How Can an Adult Autism and ADHD Assessment Help?
A specialist assessment explores your experiences across your entire lifespan rather than relying on a checklist alone.
This typically includes:
- A detailed developmental history
- Discussion of childhood experiences
- Exploration of current strengths and challenges
- Assessment of social communication
- Consideration of sensory differences
- Evaluation of executive functioning skills
- Screening for co-occurring mental health difficulties
A high-quality assessment can clarify whether:
- Autism is present
- ADHD is present
- Both conditions are present
- Another explanation better accounts for your experiences
Many adults describe diagnosis as a turning point that enables them to better understand themselves and access appropriate support.
Should You Seek an Assessment?
If you have spent years wondering:
- Am I autistic?
- Do I have ADHD?
- Why do everyday tasks feel harder than they seem for others?
- Why do I experience repeated burnout?
- Why do I feel different despite appearing to cope?
Then a formal assessment may provide clarity.
There is no right or wrong reason to seek an assessment. For many people, the goal is not obtaining a label but gaining a deeper understanding of how their brain works and identifying strategies that support wellbeing.
Final Thoughts
Being both autistic and having ADHD is more common than many people realise. While the combination can create unique challenges, it can also bring strengths including creativity, innovation, deep expertise, problem-solving skills and original thinking.
If this article resonates with your experiences, remember that you are not alone. Many adults discover their neurodivergence later in life and find that understanding themselves through a neurodiversity-affirming lens is both validating and empowering.
If you would like to explore whether autism, ADHD or both may be contributing to your experiences, you can complete our free autism and ADHD screening questionnaires or learn more about our specialist adult assessment services.
References
Antshel, K.M. and Russo, N. (2019) Autism spectrum disorders and ADHD: Overlapping phenomenology, diagnostic issues and treatment considerations. Current Psychiatry Reports, 21(5), pp.1-11.
Lai, M.C. and Baron-Cohen, S. (2015) Identifying the lost generation of adults with autism spectrum conditions. The Lancet Psychiatry, 2(11), pp.1013-1027.
Rommelse, N.N.J., Geurts, H.M., Franke, B., Buitelaar, J.K. and Hartman, C.A. (2010) A review on cognitive and brain endophenotypes that may be common in autism spectrum disorder and attention-deficit/hyperactivity disorder and facilitate the search for pleiotropic genes. Neuroscience & Biobehavioral Reviews, 35(6), pp.1363-1396.
