Signs and Symptoms

ADHD is characterized by a combination of inattention, hyperactivity, and impulsivity. These symptoms are categorized into two domains:

• –Inattention: Difficulty sustaining attention, following through on tasks, and organizing activities.
• –Hyperactivity and Impulsivity: Excessive fidgeting, inability to remain seated, interrupting conversations, and acting without consideration of consequences.

According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), symptoms must be present for at least six months, appear in two or more settings (e.g., home, school, work), and interfere with social, academic, or occupational functioning. Several symptoms should have been present before age 12. [Source: DSM-5]

Causes

Genetic Factors

ADHD has a strong genetic component, with heritability estimates ranging from 70% to 80%. Multiple genes are implicated, particularly those involved in dopamine regulation, which affects attention and behavior control. [Source: Nature Reviews. Disease Primers, 2024]

Environmental Factors

Non-genetic factors may also contribute to ADHD, including prenatal exposure to tobacco smoke, alcohol, or drugs; premature birth; low birth weight; and lead exposure. However, these factors are less influential compared to genetic predisposition. [Source: Journal of Clinical and Experimental Neuropsychology, August 2011]

Diagnosis

Diagnosis involves a comprehensive evaluation, including clinical interviews, behavioral assessments, and gathering information from multiple sources such as parents, teachers, and self-reports. The DSM-5 criteria are commonly used, requiring:

• –Presence of at least six symptoms of inattention and/or hyperactivity-impulsivity for children up to age 16, or five for adolescents 17 and older and adults.
• –Symptoms present before age 12.
• –Symptoms occurring in two or more settings.
• –Clear evidence that symptoms interfere with or reduce the quality of social, academic, or occupational functioning. [Source: DSM-5]

Treatment

Pharmacological Interventions

Medications are a primary treatment for ADHD and include:

• –Stimulants: Methylphenidate and amphetamines are first-line treatments that increase dopamine and norepinephrine levels, improving attention and reducing hyperactivity and impulsivity. [Source: Molecular Psychiatry, April 2019]
• –Non-Stimulants: Atomoxetine, a selective norepinephrine reuptake inhibitor, and guanfacine, an alpha-2 adrenergic agonist, are alternatives for those who do not respond to stimulants or experience adverse effects. [Source: Journal of the American Academy of Child & Adolescent Psychiatry, 1998]

Behavioral Therapies

Behavioral interventions focus on developing coping strategies and modifying behaviors. Techniques include:

• –Cognitive Behavioral Therapy (CBT): Helps individuals develop skills to manage symptoms and improve functioning. [Source: Routledge]
• –Parent Training: Educates parents on effective strategies to manage their child's behavior. [Source: National Guideline Clearinghouse, March 2012]

Epidemiology

ADHD is a common disorder affecting children and adults worldwide. Prevalence rates vary due to differences in diagnostic criteria and cultural factors. In the United States, approximately 10% of children aged 3 to 17 have been diagnosed with ADHD, compared to 3.2% in Sweden. [Source: Financial Times, June 2025]

A 2024 study estimated that about 15.5 million U.S. adults have ADHD, with many facing challenges in accessing treatment. [Source: Reuters, October 2024]

History

Descriptions of behaviors resembling ADHD date back to the 18th century. In 1798, Sir Alexander Crichton described "mental restlessness" in children. The first clinical description is attributed to George Still in 1902. The term "attention deficit disorder" (ADD) was introduced in the DSM-III in 1980, later revised to ADHD in the DSM-III-R in 1987. [Source: Child and Adolescent Mental Health, May 2001]

Prognosis

ADHD often persists into adulthood, with about 30% to 50% of individuals diagnosed in childhood continuing to experience symptoms. Adults with ADHD may develop coping mechanisms, but challenges in occupational and social settings can persist. Comorbid conditions such as anxiety and depression are common, and there is an increased risk of substance abuse and other mental health issues. [Source: World Journal of Psychiatry, March 2017]

Recent Developments

Recent research indicates that the surge in ADHD diagnoses and medication prescriptions is primarily due to increased public awareness and reduced stigma, rather than an actual increase in prevalence. A systematic review of studies since January 2020 found that while diagnostic rates have risen, the actual prevalence of ADHD has remained stable. [Source: Financial Times, June 2025]

Additionally, the COVID-19 pandemic has influenced ADHD diagnosis and treatment patterns. Telehealth services have expanded access to care, but medication shortages have posed challenges for patients. [Source: Reuters, October 2024]