Adult ADHD represents persistence of symptoms from childhood into adulthood, with approximately 50-65% of children diagnosed with ADHD continuing to meet criteria as adults. Adult ADHD presentation differs from pediatric: hyperactivity often manifests as restlessness, fidgeting, or feeling 'driven by a motor' rather than overt running/climbing; inattention causes distractibility, disorganization, forgetfulness, time management difficulties; impulsivity manifests as interrupting, hasty decisions, financial impulsivity, and emotional dysregulation. Executive dysfunction is prominent, affecting working memory, planning, prioritization, task initiation, and self-monitoring. The disorder substantially impacts academic achievement, occupational functioning, relationships, driving safety, and risk of comorbid substance use disorders.
Diagnosis requires DSM-5 criteria including symptoms persisting since childhood (before age 12), present in multiple settings, causing significant impairment, and not better explained by another disorder. Diagnostic assessment includes structured clinical interview, validated rating scales (Adult ADHD Self-Report Scale ASRS, Conners' Adult ADHD Rating Scales), retrospective childhood symptom assessment (Wender Utah Rating Scale), collateral information from family or partners, neuropsychological testing in some cases, and screening for common comorbidities (mood disorders 50%, anxiety disorders 50%, substance use 30%, learning disorders, sleep disorders). Differential diagnosis includes mood disorders, anxiety, sleep apnea, substance use, thyroid dysfunction, and personality disorders.
Pharmacotherapy is highly effective with 70-80% response rates. Psychostimulants are first-line: methylphenidate formulations (immediate-release, extended-release Concerta, Metadate, Ritalin LA, transdermal Daytrana) and amphetamines (mixed amphetamine salts Adderall and Vyvanse, dextroamphetamine). Long-acting formulations preferred for adherence and abuse deterrence. Side effects include decreased appetite, weight loss, insomnia, increased blood pressure and heart rate (cardiovascular monitoring required, ECG before initiation in those with risk factors), dry mouth, headache, and rebound symptoms. Non-stimulant alternatives include atomoxetine (selective norepinephrine reuptake inhibitor, slower onset weeks but no abuse potential), viloxazine (newer NRI), alpha-2 agonists (guanfacine, clonidine extended-release), and bupropion off-label. Selection considers comorbidity (avoid stimulants in active substance use, prefer atomoxetine), cardiovascular risk, sleep architecture, and abuse potential. Comprehensive treatment combines pharmacotherapy with cognitive behavioral therapy specifically adapted for adult ADHD, organizational coaching, exercise (significant evidence for symptom improvement), sleep optimization, and treatment of comorbid conditions.