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Understanding Adult ADHD

What is Adult ADHD?

Attention-Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder which affects children and adults. It is typically characterised by difficulties in concentrating, problems with certain behaviours and problems with impulse control. In adults, it is not uncommon for ADHD to cause problems with emotional regulation, sleep problems, and problems with self-esteem. Adult ADHD is estimated to effect around 3-4% of adults in the UK.

We now understand that there are several categories of ADHD. Some people present with predominantly hyperactive presentations, and others with predominantly inattentive presentations. Where both a present, ADHD is deemed a ‘combined type’.


What are the symptoms of adult ADHD?

  1. Difficulties in focussing

Adults with ADHD commonly report difficulties in maintaining focus on tasks. They may find it difficult to work if there are distractions and might not be able to keep their attention on a task for very long. Procrastination is a common complaint, and people with ADHD often struggle to engage in work until close to a deadline.


  1. Problems with organisation

Adults with ADHD often struggle to stay organised, despite keeping rigorous to-do lists or calendars. They might find they miss engagements, or frequently lose essentials like their phone or keys.


  1. Mind-wandering

Adults with ADHD may become distracted by their own thoughts. They often report difficulties in sticking to one task and might notice they struggle to read a book or watch a film through to the end.


  1. Listening difficulties

Many adults with ADHD report being told they look dreamy or preoccupied, even when spoken to directly.


  1. Restlessness

People with ADHD often report difficulties in sitting still. Adults have often worked to mask some of these symptoms, however they may find they are uncomfortable sitting still for long periods, or that they tend to prefer to have something in their hand to play with.


  1. Impulsivity

Adults with ADHD often struggle with being too impulsive. This is commonly seen in conversation, where they might struggle to wait for their turn to speak. People with ADHD often report feeling very frustrated when needing to wait in queues.


  1. Emotional difficulties

Adults with ADHD often struggle with mood swings and might find their mood changes quickly throughout the day in response to small things going wrong.


  1. Sleep issues

ADHD is associated with a range of sleep difficulties, most commonly a ‘delayed sleep phase’. This means that they do not tend to feel tired until later in the night and tend not to get as much sleep as they would like.


Adults with ADHD have often become very adept at masking their symptoms in certain situations. These masking behaviours usually take a great deal of mental effort and may make a person with ADHD feel mentally exhausted.


What causes ADHD?

ADHD is a neurodevelopmental disorder, which means it is a problem formed in the developing brain. The exact cause of ADHD remains unknown; however it appears that a person’s genetics plays a pivotal role. In addition, problems immediately before or after birth are known to contribute.

Lots of adults who were not diagnosed as children have long struggled with their symptoms. Recently, there has been a general increase in the coverage of ADHD in the news and on social media, prompting adults to question whether they may have it.


How is ADHD diagnosed at Cognacity?

ADHD is a clinical diagnosis, which means it is based on a clinical assessment, rather than a blood test or scan. At Cognacity, we carry out our ADHD assessments to the highest standards. Our ADHD assessments are conducted in two parts, usually held on separate days. It is vital that at least one of these parts is conducted face-to-face, as there is a requirement for a brief physical examination.

Part 1 of our assessment process is a general psychiatric assessment with a focus on the core symptoms of ADHD. If there is sufficient evidence of ADHD at the end of this assessment, you will be invited to return for the Part 2 assessment. If it is felt that you are unlikely to meet diagnostic criteria at the end of Part 1, you will not need to complete Part 2. Your clinician will offer an alternate follow-up plan, if relevant.

Part 2 of our assessment process includes completion of the DIVA-5, a gold-standard diagnostic interview for adult ADHD. If you meet diagnostic criteria for adult ADHD, your clinician will talk you through what this means, and what the next steps might be.


What happens if I receive a diagnosis of adult ADHD?

At Cognacity, all our adult ADHD assessments are conducted by psychiatrists with special experience in the diagnosis and management of adult ADHD. This means that if you chose to explore medication as part of your treatment for ADHD, there will be no need to join a waiting list for prescribing. Most uncomplicated cases allow for the start of a medication trial at the end of your Part 2 assessment. We take a neuro-affirmative approach to the management of ADHD, and seek to nurture your strengths as well as address any limitations.

We also offer comprehensive psychiatric follow-up to all adults diagnosed with ADHD. This may include medication titration reviews, psychoeducational sessions or referral to one of our specialist behavioural therapists for the psychotherapeutic management of ADHD.

If you would like more information about how Cognacity can help or to make an appointment please contact us on: 020 3219 3080 or

Meet our ADHD clinicians

Dr Dominic de Souza

Dr Dominic de Souza

Consultant Psychiatrist

Dr Dominic de Souza qualified from Leeds University, trained in Melbourne, Australia and London and has been a Consultant Psychiatrist since 2007, working across both the NHS and private sector. As a Royal College examiner and tutor, he is involved in teaching and training of junior doctors and medical students. He also advises health insurance providers.

Dominic takes a recovery-orientated and holistic approach to assessment and treatment of adults with mental health problems. His interests include mood and anxiety disorders, psychosis, trauma, personality disorders, learning disability and ADHD. His additional forensic and legal training provides further expertise in preparing medicolegal reports ranging from criminal cases to employment/occupational matters.

Outside of work, Dominic enjoys playing and watching sports with his kids, reading and going to music concerts/festivals.

For more information on Dr Dominic de Souza please contact reception.

Dr Harrison Howarth

Dr Harrison Howarth


Dr Harrison Howarth graduated from Imperial College London School of Medicine with a distinction in medicine and a first-class honours degree in research sciences. He developed an early interest in psychiatry and completed his core training in North Central London. Harrison gained experience in the care of both inpatients and outpatients with a range of presenting illnesses including complex depression, anxiety and trauma, ADHD, psychosis, and substance misuse issues.

Harrison is published in both the fields of psychiatry and general internal medicine, with a particular research interest in the mental health of athletes competing at the elite level. He recently authored the psychiatry chapter of a medical school textbook, along with Dr Gary Bell, a colleague at Cognacity.

Harrison is a Member of the Royal College of Psychiatrists and approved under section 12(2) of the Mental Health Act as having special experience in the diagnosis and treatment of mental illness.

Outside of work, Harrison has a passion for music and plays in a folk-rock’n’roll band. He also enjoys long walks in the country with his dog, Finn.

For more information on Dr Harrison Howarth please contact reception.

Dr Alison Lennox

Dr Alison Lennox

Consultant Psychiatrist

Dr Alison Lennox is a Consultant Psychiatrist and an expert in neurodevelopmental conditions.  She is one of few adult psychiatrists in the UK with specialist expertise in the assessment of Adult Autism.  Outside of her work with Cognacity, Alison is a Clinical Lead for the Buckinghamshire NHS Adult Autism Diagnostic Service.  Alison is a member of the Executive Committee for the Royal College of Psychiatrists Neurodevelopmental Special Interest Group.  She is delighted to have been invited to contribute to the National Autism Training Programme for Psychiatrists.

Alison read for an undergraduate degree at the University of Cambridge before completing her medical degree at University College London.  She trained as a doctor in Oxford and became a member of the Royal College of Psychiatrists in 2014.  Today when time permits, she tutors and examines Oxford University medical students in clinical communication.

She has significant experience in the interplay of Autism and other neurodevelopmental conditions such as ADHD.  She delivers a weekly NHS adult ADHD clinic providing diagnostic assessments, medication titrations, and Shared Care recommendations.

Alison is regarded as a compassionate doctor who is focused on delivering high quality Autism assessments by understanding and supporting the experience of individuals.  She provides a careful, accurate and thoughtful assessment with individualised recommendations.

Her training in general and liaison psychiatry means Alison is also able to understand the interplay of neurodevelopmental, mental health and medical conditions.  She is particularly interested in commonly co-occurring conditions such as eating disorder and OCD and understands different autistic presentations and masking.

In her leisure time Alison enjoys Peloton, following Formula One, poetry, and walking her dog in the countryside.

For more information on Dr Alison Lennox please contact reception.

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ICO Registration:

Cognacity Health Ltd - ZB425974

Cognacity Ltd - ZA392828

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