Undiagnosed ADHD in Adults

Undiagnosed ADHD in Adults

While ADHD is more commonly diagnosed in children, many adults struggle with undiagnosed adult ADHD, often without realising it. It is estimated that 2-5% of the adult population has ADHD, many of whom are undiagnosed and not getting the support or treatment needed to manage the symptoms. 

What is ADHD?

ADHD (Attention Deficit Hyperactivity Disorder) is a neurodevelopmental disorder characterised by persistent attention, hyperactivity or impulsivity difficulties (or both). Adults who have lived with ADHD without realising it may put many signs and symptoms down to personality traits. Symptoms like having trouble focusing, sitting still, following through with tasks, and controlling impulses can all be overlooked by caregivers and teachers. Still, when the signs and symptoms continue to negatively affect an individual’s quality of life, it is essential to seek mental healthcare advice. 

Why is it important to get an ADHD diagnosis?

Seeking an ADHD diagnosis in adulthood can significantly impact daily functioning and build a better understanding of how to work with neurodiverse benefits to enhance different areas of life. Many individuals with undiagnosed ADHD struggle with academic or occupational performance, relationships, and emotional well-being.

Adults with ADHD may experience difficulties with time management, organisation, and decision-making and may also have challenges with self-esteem and self-confidence. However, it doesn’t need to be a struggle; seeking professional mental health support can lead individuals to reach their full potential with greater ease, happiness, and self-compassion. 

What are the signs and symptoms of undiagnosed ADHD in adulthood?

The symptoms of undiagnosed ADHD in adulthood can vary depending on the individual, but some common signs include the following:

  • Difficulty focusing attention: Getting easily distracted during tasks or conversations that are not stimulating enough can cause problems when following through with instructions.
  • Trouble with time management: Without the proper techniques to keep track of appointments or essential details, problems can persist throughout a person’s personal and professional life.
  • Impulsivity: Acting impulsively, making decisions without considering the consequences, interrupting others during conversations, or engaging in risky behaviour.
  • Hyperactivity: The ‘H’ in ADHD can express itself with restless behaviour, which includes constantly being on the move, fidgeting, or tapping fingers or feet.
  • Self-esteem issues: Chronic difficulties with attention, organisation and time management can lead to frustration, self-doubt, and low self-esteem.
  • Relationship problems: Adults with undiagnosed ADHD may struggle with communication and maintaining relationships, leading to social and emotional issues.


It is important to note that these symptoms may also be present in individuals without ADHD, and a proper diagnosis requires a comprehensive evaluation by a qualified mental health specialist who specialises in diagnosing ADHD as well as recognising other mental health conditions. 

Can ADHD symptoms persist into adulthood?

ADHD is often considered a childhood disorder, but the symptoms can persist into adulthood in many cases, even if they were not recognised or treated in childhood. It is estimated that up to 60% of children with ADHD continue to experience symptoms into adulthood. It is common for adults with undiagnosed ADHD in childhood to develop coping mechanisms to manage their symptoms. However, these coping mechanisms may not be effective in adulthood, especially in complex and demanding situations, sometimes leading to other mental health challenges which overlap with ADHD. 

Moreover, the symptoms of ADHD can change as an individual grows older. For instance, hyperactivity may be less noticeable in adults, but difficulties with attention and impulsivity may persist. Recognising and treating ADHD in adulthood is crucial because it can significantly impact an individual’s well-being, academic or occupational performance, and overall quality of life. With appropriate treatment, individuals with ADHD can learn to manage their symptoms effectively, improve their daily functioning, and achieve their goals.

What are the challenges of a late ADHD diagnosis in adulthood?

Diagnosing ADHD in adults can be challenging for two main reasons:


  1.  Lack of awareness or understanding of ADHD in adults
  2.  Overlap with other mental health conditions or medical issues


Diagnosing ADHD in adulthood requires a comprehensive evaluation by a healthcare professional, such as a psychiatrist with expertise in ADHD. A Onebright Adult ADHD Assessment will include a thorough assessment of symptoms, medical history, and family history guided by a clinical psychiatrist. 

How to get an adult ADHD diagnosis?

Getting an ADHD diagnosis as an adult in the UK is notoriously difficult — with reports of some people waiting up to five years to see a mental health professional. For fast, effective, quality mental healthcare, Onebright offers private ADHD Assessments and treatment pathways for individuals looking to fast-track their diagnosis. 

Why is it important NOT to self-diagnose ADHD?

A formal medical diagnosis followed by treatment can improve an individual’s quality of life by helping manage symptoms and improve relationships, work, and academic performance. It’s important to remember that ADHD is not a character flaw or a lack of willpower. It’s a neurodevelopmental disorder that can be effectively managed with treatment. Seeking help and support can significantly improve daily life and overall well-being. 

Treating ADHD with evidence-based Cognitive Behavioural Therapy

Many people find Cognitive Behavioral Therapy (CBT) helpful, focusing on changing negative thinking and behaviour patterns. CBT can help individuals develop coping skills, organisational strategies, and time-management techniques to manage symptoms effectively. This therapy can be done online or face-to-face and can be especially beneficial for those who cannot or choose not to take medication. Get in touch with Onebright to enquire about an ADHD diagnosis. 

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