Adult ADHD

Adult Attention-Deficit / Hyperactivity Disorder (ADHD) is a neuro-developmental disorder that involves symptoms relating to inattention, impulsivity and hyperactivity. While at least 1 in 20 people likely have ADHD, it is under-diagnosed in Australia and internationally.

ADHD is often misunderstood. It can cause problems:

concentrating
becoming distracted
being hyperactive (sometimes)
being impulsive

This may cause people with ADHD to have problems with their:

schooling
friendships & relationships
work
family life

Many clients seek out counselling for secondary issues that may develop in large part due to ADHD difficulties of boredom, lack of stimulation, disorganisation, distractibility, etc (e.g. addictions, mood disorders, emotion dysregulation, work and study stress, relationship difficulties, etc). As a result, clients may struggle with these secondary issues, masking underlying ADHD. Aligned with Australian ADHD Guidelines, Brydan regularly screens for ADHD with clients in high risk populations.

While psychologists can assess and diagnose adult ADHD, they are unable to prescribe appropriate ADHD medication, requiring assessment by an psychiatrist, which can be costly. Brydan provides stand-alone screening, to help clients decide whether to proceed with a full ADHD Assessments.

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Adult ADHD Overview

Adult ADHD is underdiagnosed in Australia and internationally. Symptoms include inattention, impulsive and hyperactive feautures, developing prior to 12 years of age (whether we notice them or not). Earlier identification can lead to earlier intervention, and better outcomes. Unfortunately, co-occuring conditions is more of the rule than the exception, and according to Austraian ADHD Guidelines, clients in high risk groups should consider screening for ADHD.

ADHD Symptoms

ADHD can present in 3 ways: 1) Inattentive symptoms — a person is easily distractible but isn’t hyperactive or impulsive. 2) Hyperactive-impulsive symptoms — a person has symptoms of impulsivity and hyperactivity. 3) Combined symptoms — a person has a mixture of symptoms including hyperactivity, inattention and impulsivity.

Onset

ADHD symptons generally start to appear prior to the age of 12. However, many people are not diagnosed until they are adults. This is possibly due to lack of awareness of ADHD symptoms, and / or learning to adapt to cope or hide their symptoms.

Aetiology / Causes

ADHD is a complex condition caused by a combination of genetic, biological, and environmental factors. It is highly heritable, meaning it often runs in families, and is linked to differences in brain chemicals like dopamine and noradrenaline. Brain imaging shows that areas responsible for attention and self-control function differently in people with ADHD. Environmental influences, such as prenatal stress, exposure to toxins, or early life trauma, can also increase the risk, often interacting with genetic predispositions to shape how ADHD develops.

Prognosis / Outcomes

ADHD is a long-term condition that significantly impacts multiple areas of functioning, with individuals often experiencing poorer educational, occupational, social, and physical health outcomes compared to their peers. While some achieve positive outcomes, these are less well understood and influenced by factors like social support, parenting approaches, and cognitive ability, highlighting the complexity and variability in ADHD prognosis.

Co-Occuring Conditions

Individuals with ADHD frequently experience co-occurring conditions, with two-thirds of children and adolescents and up to 80% of adults having at least one additional mental health disorder. Common co-occurring conditions include anxiety, depressive, and substance use disorders, with specific learning disorders, oppositional defiant disorder, and autism spectrum disorder prevalent in youth, and bipolar disorder, obsessive-compulsive disorder, and personality disorders more common in adults.

ADHD Across the Lifespan

ADHD has a characteristic course that persists across the lifespan but presents differently at various stages. Symptoms typically appear before age 12 and may only be diagnosed later when functional demands increase. Hyperactivity and impulsivity are most prominent in younger children, with inattention symptoms becoming more evident during adolescence and adulthood. Adults often experience subtler manifestations, such as restlessness, organisational difficulties, and emotional regulation issues, while older adults remain under-researched. Co-occurring conditions are common across all stages, influencing the severity and presentation of ADHD symptoms.

Adult ADHD Symptoms

ADHD in adults often presents differently compared to childhood. It can present in 3 ways:

Inattentive symptoms — a person is easily distractible but isn’t hyperactive or impulsive.
Hyperactive-impulsive symptoms — a person has symptoms of impulsivity and hyperactivity.
Combined symptoms — a person has a mixture of symptoms including hyperactivity, inattention and impulsivity.

Co-occuring Conditions

Adults with ADHD frequently have one or more co-occurring conditions, which can complicate diagnosis and treatment. Common co-occurring conditions include:

Mood Disorders: Depression and bipolar disorder, often resulting from the chronic stress and frustration associated with untreated ADHD symptoms.
Anxiety Disorders: Generalised anxiety, social anxiety, and panic disorders are prevalent due to struggles with responsibilities, deadlines, and social interactions.
Substance Use Disorders: Impulsivity and attempts to self-medicate increase the risk of addiction to alcohol, nicotine, or recreational drugs.
Autism Spectrum Disorder (ASD): Co-occurs in 20–50% of cases, adding complexity to emotional regulation, social interactions, and sensory processing.
Learning Disabilities: Dyslexia, dyscalculia, and other learning difficulties often co-occur, affecting academic and professional performance.
Sleep Disorders: Insomnia, restless leg syndrome, and other disturbances exacerbate ADHD symptoms.
Personality Disorders: Traits associated with borderline or antisocial personality disorder may appear, especially in untreated cases.
Emotional Dysregulation: Up to 40–50% of adults experience difficulties managing emotions, significantly affecting their quality of life.
Hypersexuality or Sexual Impulsivity: Impulsivity linked to ADHD can manifest as difficulty controlling sexual behaviours, risky sexual activities, or infidelity.
Low Sexual Interest or Dysfunction: Emotional dysregulation, mood disorders, or medication side effects can contribute to reduced sexual desire or difficulty maintaining intimate relationships.

Common Myths About Adult ADHD

Myths surrounding adult ADHD often stem from a combination of historical misunderstandings, societal attitudes, and a lack of awareness about how ADHD presents in adulthood. Here are some key reasons why these myths exist:

Historical Focus on Children
Misunderstanding of ADHD Symptoms in Adults
Stigma and Lack of Awareness
Overlap with Other Mental Health Conditions
Lack of Research on Adult ADHD
Cultural Perceptions of Productivity and Success
Belief that ADHD is Overdiagnosed
Misconceptions About Medication
Cognitive Bias and Lack of Exposure
Cultural Factors

1. ADHD is just a childhood disorder.

ADHD can continue into adulthood. Many adults are diagnosed later in life after struggling with symptoms like poor focus, time management issues, and disorganisation, which were overlooked in childhood. They may also report that they became aware of their symptoms following the diagnosis of their children with ADHD, and sharing similar features.

2. People with ADHD are lazy or disorganised.

ADHD is a neurodevelopmental disorder, not a result of laziness. It affects the brain’s ability to manage attention and control impulses, making everyday tasks harder to manage. Some clients report that being called 'lazy' as a child by parents or teachers is a common memory.

3. Adults with ADHD can't keep a job.

While ADHD can make work challenging, many adults with ADHD have successful careers. With the right strategies, such as time management tools and sometimes medication, they can manage symptoms and excel in their jobs. ADHD can bring both positive and challenging symptoms, to be harnessed and managed.

Adults with ADHD may be drawn to:

entrepreneurship
creative fields
sales and marketing
emergency services
healthcare
teaching and education
technology and IT
journalism and media.

4. ADHD is overdiagnosed in adults.

While more adults are being diagnosed with ADHD now, many adults with the condition remain undiagnosed for years. ADHD can be confused with other conditions like anxiety or depression, but this doesn’t mean it’s overdiagnosed.

The rising number of adult ADHD diagnoses is not due to an increase in cases, but rather improved awareness, better healthcare access, and reduced stigma, leading to more adults seeking diagnosis and treatment. Previously, ADHD was thought to mainly affect children, with symptoms often fading in adulthood.

The costs and difficulty of access to healthcare can be significant barriers to adult ADHD diagnosis. Many individuals face long wait times, expensive consultations, and limited access to specialists, making it challenging for them to receive a timely and accurate diagnosis. These factors can delay treatment and contribute to the ongoing struggles that many adults with ADHD experience.

5. Medication is the only treatment for ADHD.

6. All adults with ADHD are hyperactive.

Hyperactivity is common in children with ADHD, but adults often don’t show this. In adults, symptoms like restlessness, difficulty focusing, procrastination, and disorganisation are more common.

7. ADHD always causes impulsivity and poor decision-making.

While impulsivity and difficulty making decisions are common, they’re not constant. Many adults with ADHD can make thoughtful decisions with the right support and strategies in place.

8. Adults with ADHD can’t have successful relationships.

ADHD can affect relationships, but with good communication and treatment, many adults with ADHD have healthy and successful relationships.

9. ADHD isn’t a "real" disorder for adults.

ADHD is a recognised neurodevelopmental disorder. It is supported by research and accepted by major health organisations like the World Health Organisation and the NHS.

10. People with ADHD just need to "try harder" to focus.

ADHD isn’t about trying harder. It’s a brain-based condition that makes focusing difficult. Adults with ADHD often struggle more with tasks that are boring or require long periods of attention, even if they try their best.

Inattentive symptoms

People with inattentive ADHD may have these symptoms:

a tendency to start but not finish tasks
putting off tasks that need sustained effort
being easily distracted or daydreaming
having trouble remembering things
having difficulty organising tasks, activities, belongings or time
losing things
not following instructions
not paying attention to detail and making careless mistakes
struggling to focus and concentrate on tasks they find boring or tedious

Hyperactive-impulsive symptoms

People with hyperactive-impulsive ADHD may have these symptoms:

fidgeting and squirming more than others
talking non-stop and interrupting conversations
blurting out answers before the question has been finished
reacting quickly to situations without thinking about the consequences
badgering their parent, partner or friends when they want something
finding boredom intolerable
looking for stimulation
participating in risk taking or dangerous behaviour
choosing a smaller reward now rather than a larger reward later

Combined Symptoms

Some people have symptoms of both inattentive and hyperactive-impulsive ADHD.

Are Any Of These Familiar?

Hyperactivity tends to appear as internal restlessness or difficulty relaxing rather than overt physical activity.
Cognitive challenges include disorganisation, forgetfulness, zoning-out, poor time management, difficulty prioritising tasks, and trouble transitioning between activities.
Many adults also struggle with emotional dysregulation, including mood swings, sensitivity to rejection, and frustration intolerance.
Socially, ADHD can affect relationships, with impulsivity, poor communication, and difficulty fulfilling commitments creating tension.
Professionally, adults with ADHD may miss deadlines, show inconsistent productivity, and struggle in team environments, particularly with tasks that lack structure or immediate appeal.
Impulsivity may manifest as risky behaviours like excessive spending, binge eating, substance misuse, problematic porn-use, risky sexual behaviours, gambling, or interpersonal conflicts. On the other hand, hyperfocus—intense concentration on specific tasks of interest—can lead to neglect of other responsibilities.
These challenges often worsen during major life transitions, such as starting university, changing jobs, or becoming a parent, as increased demands highlight ADHD-related difficulties.

Mental Health Disorders

Any mental health disorder, including:

Substance use disorders (e.g., alcohol, cannabis, opioids, stimulants, or nicotine)
Borderline Personality Disorder (BPD)
Intermittent Explosive Disorder
Internet addiction (and possible gaming addiction)
Psychotic disorders
Binge Eating Disorder
Gambling Disorder
Anxiety, depressive, or bipolar and related disorders
Sleep disorders

Emotional and Behavioural Indicators

Suicidal behaviour or ideation

Neurodevelopmental and Cognitive Disorders

Autism Spectrum Disorder (ASD)
Intellectual disability
Tic disorders
Specific learning disorders
Language disorders

Developmental and Family-Related Factors

Born preterm
Low birth weight
Born with prenatal exposure to substances, including alcohol or other drugs
Close family member diagnosed with ADHD

Medical and Environmental Factors

Acquired brain injury
Imprisonment

High Risk Groups for Adult ADHD

Adults with the following conditions or experiences are at an increased risk of ADHD compared to the general population: