What Is the Minimum Duration of Symptoms for an ADHD Diagnosis According to DSM-5? 

According to the DSM-5, the ADHD symptom duration is a crucial criterion for diagnosing Attention Deficit Hyperactivity Disorder (ADHD). For an individual to be diagnosed with ADHD, the symptoms must be present for at least six months. This duration requirement ensures that the symptoms are not temporary and reflect a persistent pattern of behaviour, rather than a short-term issue. 

The diagnostic threshold is important because it helps distinguish ADHD from temporary behavioural challenges. Although the way symptoms appear in adults and children may vary, the six-month period is the same for both. At least two aspects of life, such as at work, school, or home, must be significantly hampered by the symptoms.  

Additionally, according to the DSM-5, symptoms must be out of line with the person’s developmental stage and cannot be better explained by another mental health issue. This guarantees that long-term symptoms, not sporadic ones, will be used to diagnose ADHD. 

How It Helps 

The ADHD symptom duration requirement ensures that the diagnosis is based on consistent and long-lasting symptoms, which helps differentiate ADHD from other conditions. By adhering to the duration requirement outlined in the DSM-5, healthcare professionals can make more accurate diagnoses, leading to more effective treatment and management strategies. 

Visit providers like ADHD Certify for personal consultations and expert advice tailored to your needs.   

For a deeper dive into the science, diagnosis, and full treatment landscape, read our complete guide to DSM-5 Diagnostic Guidelines.  

Harriet Winslow, BSc

Author

Harriet Winslow is a clinical psychologist with a Bachelor’s in Clinical Psychology and extensive experience in behaviour therapy and developmental disorders. She has worked with children and adolescents with ADHD, autism spectrum disorder (ASD), learning disabilities, and behavioural challenges, providing individual and group therapy using evidence-based approaches such as CBT and DBT. Dr. Winslow has developed and implemented personalised treatment plans, conducted formal and informal assessments, and delivered crisis intervention for clients in need of urgent mental health care. Her expertise spans assessment, treatment planning, and behavioural intervention for both neurodevelopmental and mental health conditions.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the author's privacy.

Dr. Rebecca Fernandez, MBBS

Reviewer

Dr. Rebecca Fernandez is a UK-trained physician with an MBBS and experience in general surgery, cardiology, internal medicine, gynecology, intensive care, and emergency medicine. She has managed critically ill patients, stabilised acute trauma cases, and provided comprehensive inpatient and outpatient care. In psychiatry, Dr. Fernandez has worked with psychotic, mood, anxiety, and substance use disorders, applying evidence-based approaches such as CBT, ACT, and mindfulness-based therapies. Her skills span patient assessment, treatment planning, and the integration of digital health solutions to support mental well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the reviewer's privacy.