ADHD is a neurodevelopmental disorder with a persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development. It is one of the most common childhood conditions, is diagnosed more often in boys, and frequently continues into adolescence and adulthood (hyperactivity tends to lessen, while inattention and restlessness often persist).

Mechanism — differences in brain networks for attention, inhibition, and self-regulation, with altered dopamine and norepinephrine signaling in the prefrontal cortex. Stimulant medicines work by increasing dopamine and norepinephrine activity, which improves attention and self-control in people with ADHD. The old idea of a "paradoxical calming" effect is not accurate.

Causes and risk factors — strongly genetic (runs in families), prematurity and low birth weight, prenatal exposure to tobacco or alcohol, and lead exposure. ADHD is not caused by poor parenting, although a chaotic environment can worsen symptoms.

Presentations (DSM-5-TR)

Diagnostic requirements — six or more symptoms in a domain (five or more at age 17 and older), lasting 6 months or more, with several symptoms present before age 12, present in two or more settings (e.g., home and school), clearly impairing functioning, and not better explained by another condition.

Common co-occurring conditions — learning disabilities (reading, writing, math), oppositional defiant disorder and conduct disorder, anxiety, depression, tic disorders, autism spectrum disorder, sleep problems, and later substance use.

• History from multiple informants — parents or caregivers and teachers (with school reports) — because symptoms must be seen in more than one setting; adolescents also report on themselves
• Developmental, school, family (ADHD in relatives), sleep, and psychosocial history (trauma, stressors)
• Screen for conditions that mimic or accompany ADHD: hearing or vision problems, sleep-disordered breathing, absence seizures, thyroid disease, anxiety, depression, learning disability, substance use
• Baseline for medication: height, weight, BMI (plotted), heart rate, blood pressure, and a cardiac history — fainting or chest pain with exercise, palpitations, known heart disease, and family history of sudden death at a young age or inherited heart rhythm problems
• Emotional state and self-esteem: children with ADHD face frequent criticism; statements such as "I'm useless" or "everyone would be better off without me" signal depression and possible self-harm risk — assess directly

• ADHD is a clinical diagnosis — no blood test or brain scan confirms it
• Standardized rating scales completed by parents and teachers (e.g., Vanderbilt scales) based on DSM-5-TR criteria
• Psychoeducational testing when a learning disability is suspected
• Hearing and vision screening; sleep study if snoring and pauses suggest sleep apnea; EEG only if seizures are suspected
• ECG is not routinely required before stimulants; obtain it (and cardiology review) when the cardiac history or examination is positive

Treatment by age (AAP 2019 guideline)

Stimulants (first-line medications) — methylphenidate products and amphetamine products (e.g., mixed amphetamine salts, lisdexamfetamine) in short-, intermediate-, and long-acting forms. Doses are titrated individually and verified with a pediatric reference.

Stimulant safety

• Common effects: decreased appetite and weight loss, insomnia, headache, stomachache, irritability or "rebound" as the dose wears off, increased heart rate and BP
• Growth: may slightly slow height and weight gain — plot height, weight, and BMI at every visit
• Tics may appear or worsen; rare psychosis or mania (new hallucinations, paranoia) — stop and report
• Boxed warning (updated 2023): high potential for misuse, abuse, addiction, and overdose; never share or sell — most misused stimulants come from family members or peers. Schedule II controlled substances
• Young children: in 2025 the FDA required labeling that children younger than 6 taking extended-release stimulants have higher drug levels, more side effects, and a risk of clinically significant weight loss (ER stimulants are not FDA-approved under 6; the label now carries a Limitation of Use statement)
• Contraindications and cautions: use with or within 14 days of an MAO inhibitor (hypertensive crisis); serious structural heart disease or serious rhythm problems (sudden death risk); agitation; history of substance misuse (prefer lower-misuse formulations, supervise). Methylphenidate: rare priapism (erection lasting over 4 hours — emergency) and peripheral vasculopathy (cold, painful, color-changing fingers or toes)

Nonstimulant medications

Behavioral and educational interventions — parent training (consistent rules, praise, rewards, effective commands), classroom behavior management, organizational skills training, school accommodations.

Listed in priority order.

1. Safety — impulsivity leads to injuries (traffic, falls, poisoning), and adolescent drivers with ADHD have more crashes; impulsivity and poor self-regulation raise the risk of substance use; assess for self-harm and suicidal thoughts, especially with depression or atomoxetine or viloxazine; screen adolescents for substance use
2. Medication monitoring — HR, BP, height, weight, and BMI at each visit; sleep, appetite, mood, tics; check for misuse or diversion (early refill requests, lost prescriptions)
3. Structure the environment
   • Reduce distractions: quiet workspace away from windows, doors, and hallways; no TV or music while doing homework; uncluttered desk
   • Seat the child near the teacher and away from distractions (but not isolated as punishment)
   • Daily routine and visual schedule; checklists and planners
4. Behavior management
   • Immediate, specific praise and rewards for desired behavior (e.g., token or point systems)
   • Clear, simple rules and one instruction at a time; make eye contact before giving directions; have the child repeat instructions
   • Consistent, calm consequences (loss of privilege, brief time-out); no physical punishment
5. Task management — break assignments into short, manageable parts, frequent brief movement breaks, timers, and praise on completion
6. Social skills — role-play turn-taking, reading emotions, and resolving conflicts; practice in real settings
7. Hospitalized child — consistent staff, structured day, active play opportunities, safety supervision, short explanations
8. Collaborate with the school — share health information for an individualized education plan or accommodation plan; school nurse administration and secure storage of medication

• ADHD is a brain-based condition, not bad parenting or laziness; combine medication (when indicated) with behavioral strategies and school support
• Medicine does not work instantly for every child — dose adjustment takes time; keep follow-up visits
• Give stimulants in the morning, with or after breakfast to reduce appetite loss; avoid late doses that disturb sleep; long-acting capsules are swallowed whole unless labeled for opening and sprinkling on soft food
• Offer a nutritious breakfast and a bedtime snack or larger evening meal when appetite returns; monitor weight
• Report: chest pain, fainting, racing heart, shortness of breath with exercise; hallucinations or paranoia; new tics; cold or discolored fingers; erection lasting more than 4 hours; worsening mood or thoughts of self-harm
• Lock up stimulants, count doses, never share, dispose of unused medicine safely
• Do not stop guanfacine or clonidine suddenly
• Parents model calm emotional regulation; avoid blame, sarcasm, and harsh criticism; notice and praise good behavior
• Consistent rules for all siblings; spend positive one-on-one time with the child
• Healthy routines: regular sleep schedule, physical activity, limited screen time before bed
• Adolescents: safe driving practices, risks of alcohol and drugs, taking responsibility for medication with supervision

• Diagnosis needs six symptoms (five at 17+), 6 months, onset before 12, two or more settings
• Gather information from parents and teachers (multiple informants)
• Most common co-occurring condition: learning disability; also ODD, anxiety, depression, tics
• Preschool (4–5): behavior therapy first; school age: medication plus behavioral therapy
• Stimulants increase dopamine/norepinephrine — not a paradoxical effect
• Stimulant side effects: appetite loss, insomnia, HR/BP rise, growth slowing — give in the morning, monitor height and weight
• Boxed warning: misuse, abuse, addiction — secure storage, no sharing
• Contraindicated with MAO inhibitors within 14 days; screen cardiac history
• Atomoxetine and viloxazine: suicidal-thinking boxed warning
• Clonidine/guanfacine: taper — rebound hypertension
• Environment: quiet workspace, no TV background, short tasks, immediate specific praise