Mental Health

Attention deficit hyperactivity disorder (ADHD)

ADHD is a neurodevelopmental disorder characterised by persistent, developmentally excessive inattention and/or hyperactivity-impulsivity that began in childhood, is present across settings and causes functional impairment.

In a nutshell

ADHD is a neurodevelopmental disorder of persistent inattention and/or hyperactivity-impulsivity that began in childhood, occurs in at least two settings and causes functional impairment. Diagnosis is specialist and clinical, supported by developmental history and collateral information; rating scales or QbTest are adjuncts only. Start with environmental modifications, use parent training first line under 5, and use age-specific medication choices when impairment persists. Monitor growth, weight, pulse, blood pressure, sleep, benefit and misuse risk, and review comorbidity and treatment at least annually.

Classic presentation

A child or adult has a lifelong pattern of inattention and/or hyperactivity-impulsivity affecting at least two settings, with corroborated functional impairment and no better explanation. A quiet inattentive presentation in a girl or woman may be missed; diagnosis still requires specialist developmental and psychosocial assessment.

Key points

ADHD is a clinical neurodevelopmental diagnosis: symptoms began in childhood, occur in at least two important settings and cause at least moderate impairment.
Rating scales, observation and QbTest can support assessment but must not be used alone to diagnose ADHD.
Under 5: offer an ADHD-focused group parent-training programme and environmental modifications; medication requires a second specialist opinion from an expert service.
Age 5 years and over: methylphenidate is first-line medication after persistent significant impairment despite environmental modifications; follow NICE sequencing after adequate trials.
Adults: lisdexamfetamine or methylphenidate are first line; consider atomoxetine when stimulants are unsuitable or ineffective after separate adequate trials.
Before and during treatment, monitor growth and weight, pulse and blood pressure, sleep, appetite, benefit, adverse effects, adherence and diversion risk; ECG is not routine when cardiovascular assessment is normal.
Treat coexisting conditions and safety risks actively; acute psychosis or mania requires ADHD medication review, and adults should have structured ADHD-focused psychological support when medication is unsuitable or insufficient.

First-line investigation

Specialist developmental, psychiatric and psychosocial assessment with collateral information from more than one setting; use rating scales or QbTest only as adjuncts and investigate mimics and comorbidity.

Management

Confirm, support and modify the environment

Agree person-centred goals, explain ADHD without blame, implement environmental or reasonable adjustments, and provide parent-training support when indicated.^1,2
Under 5, offer group ADHD-focused parent training first line; persistent significant impairment after environmental modifications requires specialist advice and medication should not be offered without a second specialist opinion.¹

Choose medication by age and response

Children aged 5 years and over: methylphenidate first line; follow NICE switching and non-stimulant sequencing after adequate trials. Adults: lisdexamfetamine or methylphenidate first line, with atomoxetine if stimulants are unsuitable or ineffective.^1,3
Use a specialist prescriber and the current BNF for formulation, licensing, dose titration, interactions, contraindications and shared-care requirements; avoid unsupported dosing shortcuts.^1,3

Monitor benefit, growth and cardiovascular safety

Measure height and weight at the NICE intervals, and monitor pulse and blood pressure before and after dose changes and every 6 months; review appetite, sleep, adverse effects, adherence, diversion and functional benefit.^1,3
Do not order routine ECGs or blood tests when cardiovascular history and examination are normal. Persistent resting tachycardia above 120 beats per minute, arrhythmia or significant blood-pressure rise on two occasions requires dose reduction and medical referral.¹

Treat comorbidity and review the whole plan

Manage anxiety, depression, autism, tics, sleep difficulty, learning needs and substance misuse alongside ADHD; review or stop ADHD medication during an acute psychotic or manic episode.^1,2
Review treatment at least annually, including benefits, adverse effects, adherence, need for dose reduction or a trial of stopping, education or work adjustments, driving, and transition between services.^1,2

Exam traps

Do not diagnose ADHD from a rating scale, a single observation or a single setting; the diagnosis is specialist and requires developmental history, impairment and pervasiveness.
QbTest is an optional adjunct for ages 6 to 17, not a standalone diagnostic test.
Do not routinely request an ECG or blood tests before or during ADHD medication when cardiovascular history and examination are normal; investigate risk features instead.
Under-5 medication is exceptional and requires a second specialist opinion after parent training and environmental modifications.
Monitor pulse and blood pressure before and after dose changes and every 6 months; persistent resting tachycardia above 120 beats per minute or significant blood-pressure rise requires dose reduction and medical referral.
Girls and women may be under-recognised, but inattentive symptoms still need childhood onset, cross-setting evidence and meaningful impairment.
Medication choice follows different first-line pathways in children and adults; detailed doses and licensing must be checked in the current BNF.

Key sources

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.