What is the primary age range for the onset of ADHD symptoms?

The primary age range for the onset of ADHD symptoms is most commonly recognized as occurring between the ages of 4 to 18 years. ADHD is typically diagnosed in childhood and the symptoms often become noticeable when children start school and face demands on their attention and self-regulation.

During this developmental period, behavioral manifestations such as inattention, hyperactivity, and impulsivity become evident, especially in structured settings. Early intervention can have a significant impact on managing the symptoms and helping the child succeed in academic and social environments.

While there can be signs of ADHD as early as 2 to 5 years of age, particularly in more active or inattentive children, the formal diagnosis is generally made later, often after children turn four, when their behaviors can be more consistently observed and compared against developmental norms.