The former name for the condition now officially called ADHD. ADD was used in the DSM from 1980 until it was replaced by ADHD in 1987. Today it is commonly used informally to describe the predominantly inattentive presentation of ADHD.
The current official medical term for a neurodevelopmental condition characterised by inattention, hyperactivity and impulsivity. ADHD has three presentations: predominantly inattentive, predominantly hyperactive-impulsive and combined.
A goal-oriented, practical support approach that helps individuals with ADHD develop personalised strategies for time management, organisation, task initiation and goal setting. Different from therapy — coaching focuses on practical skills rather than emotional processing.
A non-stimulant medication used to treat ADHD. It works by increasing norepinephrine in the brain and takes several weeks to reach full effect. It is an alternative for people who cannot tolerate stimulant medications.
A widely used screening questionnaire developed by the World Health Organisation. The six-item ASRS v1.1 is used in national surveys and clinical settings to identify adults who may warrant further ADHD assessment. A positive result is not a diagnosis.
B
Behavioural Therapy
A type of psychological treatment that focuses on changing specific behaviours through structured techniques, rewards and consequences. Used in children and teenagers with ADHD to build positive habits, reduce problem behaviour and develop self-regulation skills.
A term used to describe conditions like ADHD that arise from differences in how the brain is structured or functions, rather than from external circumstances, poor parenting or personal choice. This framing is important for reducing stigma.
C
CAMHS (Child and Adolescent Mental Health Services)
NHS services in the UK that provide assessment and treatment for children and young people with mental health and neurodevelopmental conditions including ADHD. CAMHS waiting times in many areas are very long.
CBT (Cognitive Behavioural Therapy)
A structured psychological therapy that helps people change unhelpful thought patterns and behaviours. CBT adapted for ADHD targets executive function challenges, organisation, procrastination, emotional regulation and the psychological impact of living with ADHD.
The most common presentation of ADHD, in which both inattentive symptoms and hyperactive-impulsive symptoms are significantly present. Both groups must meet diagnostic threshold criteria for at least six months.
Additional conditions that exist alongside ADHD in the same person. Common co-occurring conditions include anxiety, depression, autism, dyslexia, dyspraxia and Tourette syndrome. Between 60 and 70% of adults with ADHD have at least one co-occurring condition.
An extended-release formulation of methylphenidate used to treat ADHD. It delivers a sustained effect throughout the day, reducing the need for multiple doses compared to short-acting versions.
D
Dopamine
A neurotransmitter (chemical messenger in the brain) that plays a central role in attention, motivation, reward and impulse control. ADHD is associated with differences in how dopamine is produced, released and regulated in key brain circuits.
DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition)
The primary diagnostic manual used by mental health professionals in the United States and internationally. The DSM-5 defines ADHD as having three presentations and specifies diagnostic criteria including symptom counts, age of onset and functional impairment.
Dyslexia
A learning difficulty that primarily affects reading and spelling. It frequently co-occurs with ADHD — research suggests around 30 to 50% of people with ADHD also have dyslexia.
A neurodevelopmental condition affecting motor coordination and physical planning. Also called Developmental Coordination Disorder. It commonly co-occurs with ADHD.
E
Emotional Dysregulation
Difficulty managing emotional responses — emotions may feel more intense, shift more rapidly or be harder to control than in neurotypical people. Although not a formal diagnostic criterion for ADHD, emotional dysregulation is widely recognised as a common and significant feature of the condition.
A set of mental processes that help people plan, focus, remember instructions, manage time and regulate behaviour. Executive function includes working memory, cognitive flexibility and inhibitory control. ADHD primarily affects executive function, which explains why its impact goes far beyond simply "not paying attention".
Elvanse / Vyvanse (Lisdexamfetamine)
A stimulant medication used to treat ADHD. It is a prodrug that is converted to active dextroamphetamine in the body. Elvanse is the brand name used in the UK; Vyvanse is used in the United States and elsewhere.
F
Frontal Lobe
The part of the brain responsible for executive function, decision-making, impulse control and self-regulation. Research shows that in people with ADHD, the frontal lobe and its connections develop more slowly and may function differently throughout life.
H
Hyperactivity
One of the three core symptom groups of ADHD. In children it may appear as excessive physical movement, inability to stay seated and constant restlessness. In adults and teenagers it more often presents as inner restlessness, racing thoughts and an inability to slow down mentally.
A state of intense, sustained concentration that some people with ADHD experience when engaged in tasks they find highly interesting or stimulating. Hyperfocus can be productive but may also cause people to lose track of time, ignore other responsibilities or struggle to switch tasks.
Hyperactive-Impulsive Presentation
The ADHD presentation characterised primarily by restlessness, excessive activity and impulsive behaviour, without prominent inattentive symptoms. More commonly identified in boys and children than adults. In adults, physical hyperactivity often reduces, being replaced by inner restlessness.
One of the three core symptom groups of ADHD. It involves acting, speaking or deciding without sufficient forethought. Impulsivity reflects difficulties with inhibitory control — the ability to pause before responding.
One of the three core symptom groups of ADHD. It includes difficulty sustaining focus, poor organisation, forgetfulness, distractibility and failure to complete tasks. Inattention does not mean the person cannot pay attention — it means they struggle to regulate attention consistently.
The ADHD presentation in which inattentive symptoms are predominant, without significant hyperactivity or impulsivity. Formerly known as ADD. More commonly seen in girls, women and adults who do not fit the hyperactive stereotype.
The effortful process of hiding or suppressing ADHD symptoms to meet social expectations. More commonly reported in women and girls with ADHD. Sustained masking is associated with exhaustion, burnout, anxiety and delayed diagnosis.
Methylphenidate (Ritalin, Concerta, Medikinet)
The most widely prescribed stimulant medication for ADHD. It works by increasing dopamine and norepinephrine activity in the brain, improving attention, reducing impulsivity and supporting executive function. Available in short-acting and extended-release formulations.
A condition relating to how the brain develops and functions, particularly affecting areas such as attention, impulse control, planning, motor coordination or communication. ADHD, autism, dyslexia and dyspraxia are all neurodevelopmental conditions.
Neurodivergent
A term used to describe people whose brains develop or function differently from what is considered typical. People with ADHD, autism, dyslexia and other neurodevelopmental conditions often use this term to describe themselves positively.
Norepinephrine
A neurotransmitter involved in attention, focus and the brain's response to stimulation. Along with dopamine, norepinephrine plays a key role in ADHD. Many ADHD medications work by increasing norepinephrine activity.
NICE (National Institute for Health and Care Excellence)
The UK body that produces guidance on health and care. NICE has published detailed guidance on the recognition, diagnosis and management of ADHD in children, young people and adults. NICE guidance is followed by NHS services across England.
P
Psychoeducation
Structured education about a condition and its management, provided to individuals and families. In ADHD, psychoeducation helps people understand how the condition affects them, reduces shame and improves engagement with treatment.
The formal DSM-5 terms for the inattentive and hyperactive-impulsive ADHD presentations. "Predominantly" indicates that while symptoms from one group are dominant, some symptoms from the other group may still be present below diagnostic threshold.
Intense emotional pain triggered by perceived or real rejection, criticism or failure. Commonly reported in people with ADHD. While not a formal diagnostic criterion, RSD is increasingly recognised by ADHD specialists as a significant feature of the lived experience of ADHD.
Right to Choose
An NHS policy in England that allows patients to choose an NHS-funded assessment at any provider — including private providers — that offers NHS ADHD services. This can significantly reduce waiting times for ADHD assessment compared to standard NHS pathways.
A short-acting formulation of methylphenidate — one of the most widely known ADHD medications. Ritalin typically lasts 3 to 5 hours and may need to be taken multiple times per day.
S
SENCO (Special Educational Needs Coordinator)
A teacher in UK schools with responsibility for coordinating support for students with special educational needs, including ADHD. A SENCO can provide classroom accommodations, refer for assessment and help implement Education, Health and Care plans.
Shared Care Agreement
A formal arrangement in the UK where an ADHD specialist initiates medication and a GP then takes over prescribing and monitoring. This allows patients to receive repeat prescriptions from their GP rather than returning to a specialist clinic each time.
Stimulant Medication
The most commonly prescribed class of ADHD medication. Stimulants — including methylphenidate and lisdexamfetamine — increase dopamine and norepinephrine activity in the brain. Between 70 and 80% of people with ADHD respond well to stimulant medication.
The difficulty some people with ADHD have in perceiving and managing time accurately. This can include chronic lateness, underestimating how long tasks take, losing track of time and struggling to plan ahead effectively.
Tourette Syndrome
A neurodevelopmental condition characterised by repetitive involuntary movements and vocalisations called tics. Tourette syndrome commonly co-occurs with ADHD.
The ability to hold and manipulate information in mind over short periods. Working memory is often significantly impaired in people with ADHD, contributing to forgetfulness, difficulty following multi-step instructions and problems with organisation and planning.