ADD vs ADHD: what’s the difference?

Where the term ADD came from

Descriptions of children with marked difficulties in attention and self-control go back more than two centuries. A review of the history of ADHD traces early accounts to the Scottish physician Sir Alexander Crichton in 1798 and to the paediatrician Sir George Still’s lectures at the Royal College of Physicians in 1902.^[1] The Royal College of Psychiatrists notes that the name has changed over time, while the challenges described are those we recognise as ADHD today.^[2]

In 1980, the American Psychiatric Association’s diagnostic manual (DSM-III) used the name “attention deficit disorder”, or ADD, which could be diagnosed with or without hyperactivity. The revised edition in 1987 adopted the name attention-deficit hyperactivity disorder. Since then, ADHD has been the umbrella term — including for people who are not noticeably hyperactive at all.^[1]

How ADHD is described today

Rather than separate conditions, ADHD is now described as having different presentations, depending on which symptoms are most prominent. The NHS explains that symptoms involve your ability to pay attention (being inattentive), your energy levels (being hyperactive) and your ability to control your impulses (being impulsive) — and that most people with ADHD have symptoms of both the inattentive and hyperactive-impulsive types, while some only show signs of one.^[3]

In the UK, NICE says that for a diagnosis, symptoms should meet the diagnostic criteria in DSM-5 or ICD-11 (the World Health Organization’s classification), cause at least moderate impairment, and occur in two or more important settings — such as home, work, education or social life.^[4]

The three presentations at a glance

Examples are illustrative, not a checklist. Only a specialist can assess whether — and how — ADHD applies to someone.

Why ‘presentation’, not ‘type’

The word presentation reflects that the picture can shift. The Royal College of Psychiatrists explains that hyperactive and impulsive symptoms tend to be more common in childhood and may become less of a challenge over time, while inattentive symptoms tend to become more of an issue in adolescence and adulthood.^[2] Someone diagnosed with “combined” ADHD at eight might look predominantly inattentive at thirty — with the restlessness felt inside rather than seen.

Why inattentive ADHD can be missed

A quiet daydreamer is far less likely to be flagged in a busy classroom than a child who cannot stay in their seat. The NHS notes that ADHD is thought to be recognised less often in women than men, possibly because women with ADHD more commonly have inattentive symptoms, which can be harder to recognise.^[3]

NICE asks professionals to be aware that ADHD is thought to be under-recognised in girls and women, who are less likely to be referred for assessment and may be more likely to receive an incorrect diagnosis of another condition.^[4] Read more in ADHD in women: why it’s often missed.

Three common misunderstandings

“ADD is a milder form of ADHD.”

Not necessarily. Inattentive symptoms can have a serious impact on work, study, money and relationships even without visible hyperactivity. NICE’s criteria focus on impairment — symptoms should cause at least moderate psychological, social, educational or occupational impairment — rather than on how noticeable they are to others.^[4]

“If you can focus on things you love, you can’t have ADHD.”

Many people with ADHD can concentrate intensely on things that interest them; the difficulty is steering attention on demand, especially towards tasks that are not naturally rewarding. The Royal College of Psychiatrists describes “hyperfocus” as something some people with ADHD experience.^[2]

“Everyone’s a bit ADHD these days.”

Most people are distracted or restless sometimes. The Royal College of Psychiatrists stresses that, for people with ADHD, these challenges usually begin in childhood, continue for most people as they grow up, and affect many areas of life.^[2] That persistence and breadth is what an assessment looks for.

Which word should you use?

In everyday life, use whichever word feels right to you — many people still say ADD, especially to describe ADHD without obvious hyperactivity. In appointments, it helps to say “ADHD” and to describe your experiences specifically: what happens, how often, where, and what impact it has.

If you think you may have ADHD, start with ADHD in adults: signs and symptoms, then read how to get an assessment in the UK.

Common questions