Does untreated ADHD trigger low mood episodes?

Posted November 19, 2025 Updated November 19, 2025 Author: Harriet Winslow, BSc Reviewed by: Dr. Rebecca Fernandez, MBBS

Untreated attention deficit hyperactivity disorder (ADHD) can lead to persistent low mood and increase the risk of developing depression. According to NHS guidance on adult ADHD and the NICE NG87 guideline on ADHD diagnosis and management, unmanaged ADHD symptoms often cause long-term emotional strain, relationship difficulties, and reduced self-esteem, all of which can contribute to episodes of low mood.

Emotional and biological links

ADHD involves changes in dopamine and noradrenaline signalling, two key brain chemicals that regulate motivation, reward, and mood. When left untreated, these imbalances can lead to frustration, irritability, and emotional exhaustion. Research published in PubMed and Frontiers in Psychiatry shows that chronic emotional dysregulation in ADHD, such as difficulty managing anger or rejection, makes individuals more vulnerable to depressive episodes.

Over time, the mental effort of coping with disorganisation, forgetfulness, or underperformance can cause burnout. This chronic cognitive overload can deplete emotional energy, resulting in fatigue and demotivation that resemble depression.

Psychosocial effects of untreated ADHD

People with undiagnosed or untreated ADHD often face repeated academic, work, or social setbacks. Rejection sensitivity and criticism from others can reinforce negative self-beliefs and feelings of failure. Studies from Wiley’s Lancet Psychiatry journal suggest that these psychosocial stressors are key drivers of low mood, particularly among women and adults diagnosed later in life.

NICE and NHS guidance on managing mood

Both NHS and NICE recommend that clinicians screen for depressive symptoms whenever ADHD is assessed or treated. Tools such as the PHQ-9 and the Mood and Feelings Questionnaire can help identify coexisting mood disorders. Treatment should be integrated and flexible. If depression is severe, it may be treated first, or therapy may run alongside ADHD treatment.

Key takeaway

Untreated ADHD can trigger and maintain low mood episodes through emotional dysregulation, chronic stress, and reduced self-esteem. Following NHS and NICE guidance, early diagnosis, medication where appropriate, and tailored psychological support such as CBT and psychoeducation can greatly reduce this risk and help improve overall emotional wellbeing.

Written by

Harriet Winslow, BSc

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.

Reviewed by

Dr. Rebecca Fernandez, MBBS

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.