Attention deficit hyperactivity disorder (ADHD) is a condition that affects people’s behaviour. People with ADHD can seem restless, may have trouble concentrating and may act on impulse . Symptoms of ADHD tend to be noticed at an early age and may become more noticeable when a child’s circumstances change, such as when they start school.
https://www.nhs.uk/conditions/attention-deficit-hyperactivity-disorder-adhd/

