Attention Deficit Hyperactivity Disorder (ADHD) - in Adults

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Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental condition characterised by symptoms of hyperactivity, impulsivity, and inattention. ADHD is often thought of as a condition that only affects children; this is not true. Although ADHD is most commonly diagnosed in childhood, it can effect anyone of any age or gender. ADHD may not be diagnosed or recognised until adulthood. 

The symptoms of ADHD can be split into two categories; hyperactivity/ impulsivity and inattention. Based on the symptoms experienced the individual is diagnosed with the hyperactive/ impulsive subtype, inattentive subtype, or combined subtype of ADHD. Between childhood and adulthood the hyperactivity/ impulsivity symptoms tend to decrease and inattention symptoms become predominant. Those with the inattentive subtype of ADHD may not be diagnosed until adulthood as inattentive symptoms often go unnoticed until they cause significant problems, such as difficulties at work.

ADHD can be caused by a combination of biological, genetic, and environmental factors. Risk factors include having a family member with ADHD, mother’s use of alcohol or drugs during pregnancy, premature birth, and exposure to environmental toxins such as lead.

ADHD cannot be cured, but there are effective treatments to teach people how to manage the symptoms of ADHD and reduce the impact that symptoms have on daily functioning. Getting treatment is important as those with ADHD may have difficulty concentrating, following instructions, completing tasks, and meeting deadlines; this can lead to problems at school and at work. It is also common for people with ADHD to struggle to maintain relationships, have low self-esteem, emotional difficulties, and substance abuse issues. Those with ADHD are also more likely to engage in impulsive or risk-taking behaviour, which can increase risk of injury or involvement in an accident (e.g. car accident).

Common symptoms
  • Difficulty concentrating and easily distracted.
  • Problems with attention.
  • Difficulty planning and organising.
  • Poor time management and prioritising of tasks.
  • Appears 'zoned out', day dreamy.
  • High concentration/ focus on tasks which are stimulating/ rewarding.
  • Difficulty completing tasks.
  • Poor attention to detail.
  • Difficulty listening and following instructions.
  • Makes careless errors and mistakes.
  • Procrastination - avoids starting tasks that require attention/ mental effort.
  • Often forgets things or loses things.
  • Impatient
  • Being restless, ‘on edge’, having difficulty relaxing.
  • Difficulty controlling emotions.
  • Engage in impulsive and risk-taking behaviours.
  • Irritability
How common is in the general population
It is estimated that around 2.5% of adults in the general population have ADHD.
Gender differences
ADHD is more common in men than women. However, the inattentive subtype of ADHD, which often goes undiagnosed, is more common among females. So the number of women with ADHD may be higher than data suggests.
ADHD symptoms are typically seen before age 12. However, ADHD may not be diagnosed until adulthood, particularly if the individual has predominantly inattentive symptoms.
Typical Course
ADHD is a chronic condition. However, the type of symptoms experienced and the impact these have can change over time. There is often a shift from more hyperactive symptoms in childhood to more inattentive symptoms in adulthood.
Common Comorbid (concurrent) Conditions
Depression, anxiety disorders, substance use disorder, bipolar disorder, personality disorders, autism spectrum disorder, learning difficulties, sleep disorders.
Common treatments

If you think you have ADHD, speak with your GP and they may refer you to a specialist for further assessment. 

ADHD treatment for adults typically involves a combination of stimulant medication, psychological therapy and education. Treatment aims to help the individual learn how to manage symptoms and develop coping mechanisms to reduce negative impacts of ADHD symptoms.


Stimulant medication can help to improve concentration, make the individual feel calmer, and reduce impulsive behaviour. This can help with performance at work/school.

Psychological Therapy:

Psychological therapy can be beneficial in helping those with ADHD learn how to manage symptoms, improve organisation and time management skills, control impulsive behaviours, and reduce the impact of symptoms in order to improve daily functioning.

Behaviour management training and social skills training can help those with ADHD learn skills to improve functioning at work/school and in social situations. 

Cognitive behavioural therapy (CBT) is a structured form of talk therapy which aims to change unhelpful thoughts and behaviours. CBT can be important in addressing the other emotional and behavioural problems which can occur alongside ADHD, such as depression, anxiety, and substance misuse.