AuDHS
DESCRIPTION:
AuDHS: Autism and ADHD at the same time? Experiencing stimulus-seeking and stimulus sensitivity in everyday life as a neurodivergent person. Tips for dealing with sensory overload.
Autism and ADHD at the same time: When both diagnoses affect a person's life – Understanding AuDHS
🧭 AuDHS, when autism and ADHD meet: A guide to diagnosis and everyday life
Welcome to our specialised section on AuDHS. More and more people are recognising that they have both autism and ADHD – an internal balancing act that is often only recognised at a late stage.
Here you will find information on neurodivergence, guidance on AuDHS diagnosis for adults, and answers to why you often fluctuate between inner restlessness and the need for structure. We shed light on the paradox of sensory overload and boredom and explain the background of autism spectrum disorder comorbidity with ADHD.
🧠 A note about our design (neuro-inclusive reading)
We know that long texts can often be exhausting for neurodivergent brains. That's why this blog is designed to be "AuDHS-friendly":
· TL;DR (Too Long; Didn't Read): You will find a summary at the beginning of each article.
· Scannability: We use bold type for key terms and lots of bullet points so you can grasp the most important information at a glance.
· Clarity: We avoid walls of text and focus on short, digestible paragraphs.
TL;DR: The combination of autism and ADHD is considered by many to be rare, yet according to research, it affects up to 70% of all autistic people. This article explains what both diagnoses have in common, why stimuli, food and daily structure are so challenging, and what sound diagnosis and therapy can look like.
1. What is AuDHS, and how does the combination of autism and ADHD arise?
Autism and ADHD together in one nervous system sounds like a medical rarity, but it is not. The term AuDHS is composed of autism and ADHD and describes people who have both neurobiological developmental characteristics at the same time. For a long time, the DSM-5 diagnostic system held that a person could have autism or ADHD, but not both. This restriction was lifted in 2013. Since then, the combined diagnosis has been recognised. The term AuDHS originates from the community and describes the experience of both conditions as an inseparable unit.
Autism spectrum disorder (ASD) is a neurobiological developmental disorder that primarily affects interaction and communication as well as stereotypical, repetitive behaviours. ADHD, attention deficit hyperactivity disorder, is a neurobiological impairment characterised by inattention, hyperactivity and impulsivity. ADHD and ASD arise in early brain development, have strong genetic roots, and, when present simultaneously, create a neurobiological profile that cannot be fully captured by either diagnosis alone.
Many affected individuals do not fully recognise themselves in classic descriptions of ADHD or in typical representations of autism. This is because ADHD and autism overlap, reinforce each other and sometimes even conceal each other. Those who have both diagnoses operate under a double neurobiological requirement, and this is immediately apparent in everyday life, in self-perception and in diagnostics.
2. Is AuDHS really a rare combination? What comorbidity research says
Many people assume that the simultaneous presence of both disorders is a rare combination. The opposite is not so rare: current meta-analyses show that autism and ADHD occur simultaneously in 50 to 70% of all autistic people. Comorbidity is therefore one of the most common findings in clinical practice. Studies also show that people who are initially diagnosed with ADHD are disproportionately likely to be diagnosed with an autism spectrum disorder later on.
From a neurobiological perspective, it is not surprising that autism spectrum disorders are so often associated with ADHD. ADHD and autism spectrum disorders share genetic risk factors, overlapping brain development pathways and similar patterns in the connectivity of the prefrontal cortex. Both autism and ADHD are listed as separate developmental disorders in the ICD-10 and DSM-5, even though they have significant neurobiological overlaps. Nevertheless, many affected individuals wait years for an accurate diagnosis.
What makes the figures particularly significant is that both ADHD and autism are diagnosed much less frequently and later in women and girls. Autistic children learn early on to hide their conspicuous traits socially. People with autism spectrum disorder who also have ADHD are at increased risk of misdiagnosis, such as depression, anxiety disorder or borderline personality disorder. One of the most important findings of the last decade is that ADHD is not uncommon in combination with autism.
3. What symptoms do people with AuDHS exhibit simultaneously, and how do they differ?
The symptoms of AuDHS cannot be understood as a simple addition of ADHD and autism characteristics. When combined, both disorders produce unique patterns. Typical symptom constellations include pronounced sensitivity to stimuli paired with a simultaneous search for stimulation, a strong need for a fixed daily structure, which is regularly sabotaged by the ADHD profile, intense special interests with hyperfocus, and emotional reactions that seem disproportionate to outsiders.
The differences between ADHD and autistic characteristics are particularly evident in the social dimension. People with ADHD often have difficulty controlling their impulses and directing their attention, but actively seek social interaction. Autistic people, on the other hand, experience interaction and communication as a neurobiologically complex process. In AuDHS, these neurobiological profiles collide: the ADHD system draws people in, while the autistic profile requires intensive recovery afterwards.
People with ASD are often highly sensitive to stimuli, especially in social situations such as meetings, parties or school lessons. Symptoms such as sleep disorders, motor restlessness, hypersensitivity to certain substances or noises, and difficulties with self-regulation are common. Visually complex environments, unstructured encounters and unpredictable daily routines are particularly stressful. Those who have both autism and ADHD quickly realise that coping strategies for one diagnosis often worsen the other.
4. Stimulus processing, sensory overload and sensory sensitivity: how the nervous system is challenged
The topic of stimuli is central to AuDHS. Autistic nervous systems process sensory stimuli more intensely than neurotypical ones. Loud noises, visually busy rooms, certain proprioceptive stimuli, or external stimuli such as crowds of people can quickly overwhelm the system. At the same time, the ADHD system needs stimuli to get going. Without stimulation, the activation curve drops, and the brain actively seeks stimulus openness.
This stimulus processing creates a paradoxical pattern. Those who receive too few stimuli become restless in a manner typical of ADHD. Those who receive too many stimuli collapse under autistic overload. Stimulus overload is therefore not a rare exception, but a structural danger of everyday life. What is overlooked here is that stimulus overload often occurs with a delay; only when the person is alone and safe does the nervous system release the pent-up overload.
Neurobiologically, this is due to opposing thresholds: the dopaminergic activation system in ADHD and the stimulus processing system in autism work in opposite directions. Hypersensitivity or hyposensitivity to stimuli is not a character trait, but is neurobiologically wired. The autistic brain reacts to stimuli with increased amygdala activation and alertness. The ADHD profile, which simultaneously seeks novelty, keeps this conflict going permanently, which is what makes the clash of these two neurobiological characteristics so challenging.
5. Why is eating so often an issue in autism spectrum disorder and ADHD?
Eating is complex for autistic people and people with ADHD for several reasons, and this complexity is exacerbated when the diagnoses are combined. On the sensory side, people with autism are often highly sensitive to textures, temperatures, smells and consistencies in food. Certain food-related stimuli, such as an unexpected smell or an unfamiliar texture, can trigger strong defensive reactions. This selective eating behaviour cannot be overcome; it is sensory-conditioned.
The ADHD profile adds a second layer: people with ADHD often forget to eat, underestimate hunger or eat impulsively. The phenomenon of "food noise", intrusive thoughts about food, affects many sufferers, sometimes exacerbated by medication that suppresses hunger. In the combined diagnosis, sensory food aversions are combined with forgetful or impulsive eating behaviour, making meals a daily challenge.
Beyond eating, the sensory dimension affects many other areas of daily life, such as clothing, personal hygiene, and the sounds of other people eating (misophonia is common). Eating in company is often doubly exhausting for autistic people: sensorily, due to smells, noises, and visually distracting table settings; socially, due to expectations of small talk. The topic of eating should therefore be explicitly addressed in therapeutic support.
6. Routine, impulsivity and hyperfocus: the contradictory everyday life of people with ASD
Routine is a neurobiological safety need for autistic nervous systems. Predictable daily routines reduce alertness, conserve cognitive resources, and promote stability. The autistic brain values daily routines and suffers when they are disrupted. At the same time, the ADHD system is a declared enemy of consistent daily structures: it seeks variety, sabotages routines after a few weeks and pushes for new experiences. People with ADHD experience routine as restrictive, while autistic people need it.
Impulsivity is a core symptom of ADHD, which has particular consequences in this combination. Autistic people are often rule-oriented with clearly defined internal norms. When the ADHD system impulsively makes decisions that violate these norms, such as spontaneous changes of plan or sudden deviations from daily routines, intense self-criticism follows. Hyperactivity often manifests itself in motor activity or as covert inner restlessness that is hardly visible to the outside world.
Hyperfocus is the counterpart to impulsivity: when the brain delves into an interesting topic, an intense focus develops that lasts for hours, during which eating, sleeping, and a sense of time are blocked out. This hyperfocus is often linked to special interests, areas of deep interest that accompany autistic people throughout their lives. For self-regulation, the shift between intense focus and a complete loss of drive is one of the greatest balancing acts in the everyday life of someone with AuDHS.
7. What is masking, and why does it exhaust people with autism and ADHD in particular?
Masking describes the concealment of autistic and ADHD-typical behaviours to function socially. Typical characteristics that are suppressed by masking include self-stimulatory movements, direct communication styles and intense interests. This social camouflage requires considerable cognitive and emotional resources because the person must simultaneously regulate their own neurodivergent impulses and anticipate neurotypical expectations.
In AuDHS, masking is particularly exhausting because the ADHD system destabilises the painstakingly constructed façade. An impulsive comment, a sudden lapse in attention or intense focus can cause the masking to break down. Many people who receive their autism diagnosis as adults understand in retrospect why everyday life was so exhausting for decades: they have been masking for decades without knowing it.
Stimming, self-stimulating movements such as rocking, hand shaking or humming, has an important sensory regulatory function. Those who suppress stimming lose a neurobiological tool for coping with stress. Stimming behaviours should be recognised as legitimate strategies in therapeutic support and not suppressed. Neurodivergent people who integrate stimming as part of their self-regulation report significantly less exhaustion after social encounters.
8. Special interests and stimming: strengths and self-regulation in AuDHS
Special interests are not only a source of joy in this profile but also neurobiological regulatory tools. Intensive immersion in a topic that utilises both autistic depth and ADHD-typical hyperfocus stabilises dopamine levels and creates a deep sense of competence. Special interests are therefore not a symptom that needs to be treated, but an important building block of mental stability in neurodivergent people.
From the perspective of neurodiversity, autistic and ADHD individuals who are aware of their own regulatory strategies report significantly better well-being in studies. Physical exercise, acoustic stimulation through self-selected music, and visually calm spaces are part of the individual’s toolbox for self-regulation. People with AuDHS who know their sensory profile can use these strategies in a targeted way rather than waiting for the next crash.
The combination of autism and ADHD brings challenges, but also rare qualities of experience. The stereotype of the overwhelmed, dysfunctional neurodivergent person does not correspond to reality. Intensive pattern recognition, deep areas of interest, associative creativity, and absolute loyalty to certain values are often closely linked to special interests and have a lasting impact on the lives of neurodivergent people.
9. Diagnosis and treatment of ADHD and autism spectrum disorders: what you need to know
Diagnosis and treatment of ADHD are complex because both diagnoses must be considered simultaneously. A thorough diagnosis includes structured interviews, standardised questionnaires, a detailed developmental history and information from various areas of life. Autism and ADHD can mask each other: a child with autism who is hardly noticeable due to social camouflage often only receives an ADHD diagnosis when masking breaks down under stress.
Psychiatrists and clinical psychologists are authorised to diagnose. Diagnosis is based on DSM-5 or ICD-10. For people who are diagnosed as adults, the realisation that they have both ADHD and autism spectrum disorder is often a life-changing turning point. Many affected individuals have been confronted with misdiagnoses for years because their neurobiological profiles did not correspond to any familiar single picture.
An autism-sensitive perspective in this combination diagnosis must supplement strategies for ADHD. Standardised programmes that target neurotypical communication norms can be counterproductive for autistic clients. Schema therapy, mentalisation-based therapy and DBT elements can be easily adapted to the neurodivergent realities of life.
📖 Further reading: For a complete overview of diagnostic pathways, differential diagnoses and current research, see our article ADHD and Autism: Diagnostics in the Spectrum of Neurodiversity.
10. Living neurodiversity: What really helps people with AuDHS
Neurodiversity as a framework recognises that neurobiologically different brains are not defective versions of a standard. For autistic children and adults with this profile, this means that their need for daily structure and variety is not contradictory, but rather an honest reflection of two coexisting systems. The neurobiological profiles of people with AuDHS do not need to be cured, but rather understood and supported.
In practical terms, it helps to know one's own sensory profile: which stimuli are regulating and which are triggering? Which everyday structure provides stability without paralysing the ADHD system? Which special interests can be consciously used as sources of energy? Symptoms of AuDHS, such as social exhaustion after interaction, delayed sensory overload or the inability to break out of intense focus, can be planned for with the right understanding.
This profile will always present challenges. The crucial difference lies in knowing that impulsivity and hyperactivity can be explained neurobiologically. That autism often does not look like it does in the textbook ( ), especially in women and girls, and in people who have masked it for years. The term AuDHS is not another diagnosis, but a key to self-understanding. And that both autism and ADHD, when considered together, describe a nervous system that speaks its own language. People with AuDHS who understand this language finally find strategies that truly suit their unique constellation.
The most important points in brief
· The combination of autism and ADHD is not rare; it is not that rare at all, and affects up to 70% of all autistic people.
· Stimuli are the central issue: the autistic nervous system avoids sensory overload, the ADHD system needs stimulation, and both work simultaneously in the same body.
· Routine is neurobiologically necessary for autistic people, but is regularly sabotaged by the ADHD profile. This is a systemic conflict.
· Eating is complex for people with AuDHS for sensory and ADHD-related reasons: selective eating behaviour, forgetful food intake and sensory aversions occur simultaneously.
· Masking is particularly exhausting because it hides autistic and ADHD impulses. Stimming should be recognised as a regulatory strategy, not suppressed.
· Special interests and intense focus are regulatory tools, not disorders; they strengthen self-regulation and mental stability.
· Diagnosis requires specialists familiar with both diagnoses; misdiagnoses are common with this profile.
· Therapy strategies must be both ADHD-oriented and autism-sensitive. What helps one diagnosis can be stressful for the other.
· Neurodiversity as a framework helps: understanding, accepting and shaping one's own neurobiological profile is at the core of any effective support.
· The combination brings real challenges, but also strengths in depth, pattern recognition and the intensity of experience.
❓ Frequently asked questions (FAQ)
What do you call it when ADHD and autism occur together?
The simultaneous occurrence of autism spectrum disorder (ASD) and ADHD is referred to in the clinical context as the comorbidity of both disorders. In the affected community, the term AuDHS, composed of autism and ADHD, has become established. It does not describe two added diagnoses, but rather an independent neurobiological profile with specific patterns that are neither purely autistic nor purely ADHD-typical. Since the DSM-5 revision in 2013, the simultaneous diagnosis of both disorders has been officially possible.
Is it possible to have autism and a sensory processing disorder at the same time?
Yes, and this is particularly common in AuDHS. Atypical sensory processing is one of the core characteristics of autism spectrum disorder: up to 95% of all autistic people exhibit sensory peculiarities, either as hypersensitivity (too much) or hyposensitivity (too little). When ADHD is also present, a paradoxical pattern emerges in which the nervous system avoids stimuli on the one hand and actively seeks stimulation on the other. This coexistence of stimulus seeking and sensory overload is one of the most characteristic features of AuDHS.
What can be confused with a sensory processing disorder?
Sensory processing issues are often misinterpreted as anxiety disorders, ADHD-related distractibility, high sensitivity (HSP), obsessive-compulsive disorder or behavioural problems. In children, overreactions to stimuli are often interpreted as defiance or emotional immaturity. Conversely, a sensory processing disorder can also mask autism or ADHD: those who focus on the sensory symptoms may overlook the underlying neurobiological developmental characteristics. A thorough diagnosis by experienced professionals who are familiar with both disorders is therefore crucial.
What is an autistic shutdown, and how can it be recognised?
An autistic shutdown is a neurobiological protective reaction to sensory or emotional overload, in which the nervous system shuts down all non-essential functions. From the outside, the affected person appears calm or apathetic: they speak little or not at all, react slowly, avoid eye contact and withdraw. Internally, however, they experience a state of complete exhaustion, not relaxation, but rather a protective mode. The shutdown is not a choice, but an automatic reaction of the brain. According to a study by the University of Cambridge, 80% of 504 autistic participants report shutdowns. In AuDHS, a shutdown often occurs only when the person is alone and safe, and it often occurs with a delay.
What are the warning signs of an ADHD meltdown?
A meltdown in AuDHS manifests itself as an outward discharge reaction. Typical warning signs in the build-up phase are increasing irritability, impulsive statements, motor restlessness, loud speech and the feeling of being "under pressure". When the stimulus threshold is exceeded, crying, screaming, uncontrolled movements or verbal overwhelm occur. Unlike a shutdown, a meltdown releases the pent-up neurobiological tension outwardly. Meltdowns and shutdowns can follow one another: a meltdown can turn into a shutdown when the energy is completely depleted.
What are the warning signs of stimulus processing?
Early warning signs of atypical stimulus processing include: extreme avoidance of certain substances, noises or smells; violent reactions to light touch or unexpected stimuli; strong cravings for certain sensory experiences (rocking, pressing, rhythmic movements); difficulty in noisy or visually busy environments; recurrent exhaustion after everyday sensory environments; and difficulty eating due to textures, temperatures, or smells. In AuDHS, these warning signs often occur in a more pronounced form and are overlaid by impulsivity or hyperactivity, making them difficult to recognise.
What are the 8 sensory processing systems in autism?
Classical sensory perception recognises five senses, but sensory integration takes eight systems into account: (1) tactile (touch and pressure), (2) vestibular (balance and movement), (3) proprioceptive (body perception and muscle tone), (4) visual (sight), (5) auditory (hearing), (6) gustatory (taste), (7) olfactory (smell) and (8) interoceptive (perception of internal bodily states such as hunger, thirst, heartbeat). In autism and ADHD, atypicalities often occur in several of these systems simultaneously, especially in auditory, tactile and proprioceptive processing. The interoceptive system is often affected as well, which explains why many people with these conditions have difficulty promptly perceiving hunger or exhaustion.
Can you have ADHD without being autistic, and vice versa?
Yes. ADHD and autism are distinct neurobiological developmental characteristics that can also occur independently of each other. However, there is considerable overlap: studies show that up to 70% of all autistic people also meet the criteria for ADHD, while conversely, around 20–50% of people with ADHD exhibit autistic traits. This makes AuDHS the norm among autistic people, but both can also occur in isolation, each with its own therapeutic requirements.
What is the 30 per cent rule for ADHD?
The 30 per cent rule is a concept developed by psychiatrist Russell Barkley, which states that people with ADHD lag behind their chronological age by an average of about 30 per cent in terms of emotional and social maturity. According to this concept, a 30-year-old person with ADHD is more likely to fit the profile of a 20- to 21-year-old in areas such as impulse control and emotional regulation. This concept helps to correct unrealistic expectations, both of oneself and of outsiders. In AuDHS, this pattern can be more pronounced because autistic developmental trajectories also show imbalances between different areas of maturation.
What are the 7 things that significantly worsen ADHD?
Based on current research, the following factors are considered particularly stressful for ADHD, and even more so for AuDHS: (1) lack of sleep (regulates dopamine and attention control), (2) lack of exercise (reduces dopaminergic activation), (3) high stimulus load without control over the stimuli, (4) over-structuring without novelty slots (paralyses the ADHD system), (5) chronic social pressure and masking (exhausts self-regulation capacity), (6) lack of understanding in the environment (increases shame and pressure to conform), and (7) irregular eating (destabilises blood sugar and thus attention regulation). In AuDHS, sensory stimulus stress in particular is an independent amplifying factor that is often overlooked in pure ADHD programmes.
What is the six-second rule for autism?
The six-second rule is a communication aid for interacting with autistic people: it recommends waiting at least six seconds after asking a question or making a request before expecting a response, repeating the question or continuing to speak. Autistic nervous systems often need more time to process language and social cues and to formulate a response. In AuDHS, this processing delay can be further prolonged by ADHD-related distraction. The six-second rule is not a clinical protocol, but a practical communication principle from autism-inclusive education.
What is palilalia in autism?
Palilalia refers to the involuntary repetition of one's own words or phrases, often with increasing speed or decreasing volume. It is a form of echolalia and is considered a form of verbal stimming. Palilalia can be an expression of excitement, stress or sensory overload. In AuDHS, it can occur together with ADHD-typical speech impulsivity. Like other stimming behaviours, palilalia should not be pathologised as a disruptive symptom, but understood as an expression of a differently regulated nervous system.
What is Cassandra syndrome in autism?
Cassandra syndrome (also known as affective deprivation disorder, AfDD) describes the emotional strain experienced by neurotypical partners who feel that their emotional reality is not acknowledged in relationships with autistic people. The term is controversial among experts, as it carries the risk of blaming autistic people for relationship dynamics instead of understanding communication differences as a mutual challenge. In AuDHS, ADHD-typical patterns such as impulsive statements, forgotten agreements and emotional dysregulation are added, which can increase relationship stress. A couple-systemic perspective that takes both neurobiological profiles into account is significantly more helpful than a symptom-based blame framework.
Sources & further reading
· JAACAP (2025). Sensory Processing in Individuals With ADHD Compared With Control Populations: A Systematic Review and Meta-Analysis.
· Brain Sciences (2024). Relationships between Sensory Processing and Executive Functions in Children with Combined ASD and ADHD. DOI: 10.3390/brainsci14060566.
· ScienceDirect (2024). Sensory processing differences and internalising/externalising problems in autism: A systematic review.
· Autism Spectrum News (2025). Navigating Autistic Shutdown and Burnout Through a Neurodiversity-Affirming Approach.
· Phung, J. et al. (2021). What I Wish You Knew: Insights on Burnout, Inertia, Meltdown, and Shutdown From Autistic Youth—Frontiers in Psychology, 12, 741421.
🔗 RELATED ARTICLES: