Is ADHD different in adults than in children?

For a long time, ADHD was thought to be a childhood condition that faded away in adolescence. Research over the last few decades has shown that is incorrect: in roughly 60-70% of cases, ADHD persists significantly into adulthood.

What changes: motor hyperactivity (excessive physical fidgeting, running, climbing) tends to decrease. In adults, it often shows up instead as inner restlessness — a "revving engine" feeling, difficulty relaxing, a need to always be doing something. Impulsivity can show up as impulsive spending, frequent job changes, or difficulty holding back reactions.

What stays or worsens: inattention and problems with organization, time management, and working memory. In adulthood, demands increase (work, family, finances) while structure decreases (no more school with a fixed schedule), which makes the deficits more impactful.

Many adults are only diagnosed with ADHD in adulthood — often after years of unexplained struggles, or after a child's diagnosis. Late diagnosis is common, especially in women.