ADHD in adults

Even though a lot of research into ADHD has gone on around the world, the exact cause is still unknown. What is known is that ADHD is not caused by poor parenting, too much sugar or vaccines.

Studies of brain scans show that people with ADHD seem to have brains that look and function a little differently from other people's, so concentration and impulse control can be difficult (see references 2, 5, 8). If you have ADHD, your brain may also have difficulties processing dopamine, and you may have a dopamine deficiency.  

There is thought to be a genetic element to most ADHD, meaning it runs in families.

Studies have shown that siblings of people with ADHD are two to three times more likely to have it as well (1, 4).

Common issues faced by adults with ADHD can include:

• Poor concentration and focus
  People with ADHD experience problems with attention. You may be easily distracted by sights and sounds in your environment, quickly bounce from one activity to another, or become bored quickly. This can make it hard to focus on work or study, making it difficult to meet targets and deadlines. As a result, you may find that your marks on assignments, or your achievement at work, do not reflect your true abilities. 
  
  
• Too much concentration and focus
  On the other hand, people with ADHD also can become absorbed in tasks that are stimulating and rewarding to them, such as a new video game. When this happens, you may lose track of time or people around you and find it hard to shift your attention from the task you are fixated on. This can be a real strength when the thing you are fixated on is beneficial, but it can be challenging when it detracts from other things that you are required to do. 
  
  
• Poor time keeping and prioritising
  There are many reasons for this. You may be easily distracted; for example, on the way to work or to a social event you may feel compelled to clean the car or finish an important home task before you go out, out of fear of either forgetting the task, or not having the motivation to return to it later. People with ADHD also tend to underestimate how much time it takes to finish a task. They can incorrectly prioritise work projects and miss deadlines while being distracted elsewhere.
  
  
• Difficulties with listening skills
  Problems with attention can result in poor listening skills in many adults with ADHD, leading to missed opportunities and misunderstandings.
   
• Trouble getting organised
  Difficulties with time management and attention can mean that organising the responsibilities of adulthood, such as bills, chores, and appointments is difficult. During childhood, organisation difficulties may be less noticeable, as parents often form the structure that helps children with ADHD to manage time and responsibilities. When the young person moves into adulthood, organisational difficulties can become more pronounced. 
  
  
• Difficulty starting hard tasks
  People with adult ADHD often feel strong avoidance toward starting tasks that require a lot of attention. This procrastination often adds to existing problems, including relationship disagreements, workplace issues and problems with friends. Again, difficulties starting tasks may become more noticeable in adulthood, as the structure and guidance of school and parents lessens.
  
  
• Restlessness, trouble relaxing
  Unlike childhood ADHD, where children often appear “hyperactive”, adults with ADHD are more likely to be restless or find they can’t relax. If you have adult ADHD, others might describe you as edgy, tense or always on the go.
  
  
• Difficulty controlling emotions
  People with adult ADHD often find it hard to be patient and control impulses. Others may notice that an adult with ADHD has a tendency to interrupt other people and finish others’ sentences. They may be quick to express intense emotions. Many times, their emotion fades as quickly as it flared.
  
  
• Relationship issues
  Having ADHD can make relationships with others difficult. The partners and friends of people with undiagnosed or unmanaged ADHD may see poor listening skills and an inability to meet commitments as a sign that their partner doesn’t care. If you’re the person with ADHD, you may not understand why your partner is upset, and you may feel you’re being nagged or blamed for something that’s not your fault.

Experiences of these symptoms may differ depending on the type of ADHD someone is diagnosed with; there is hyperactive ADHD, inattentive ADHD, and combined type.

With recent research, it is becoming more apparent that the symptoms of ADHD are often different in women, girls, and people assigned female at birth (3, 6, 7). Often, girls with ADHD may show more subtle symptoms, which often leads to ADHD being missed or not diagnosed until later in life. For example, while a boy who is hyperactive may be noticed as being loud, fidgety and disruptive, a hyperactive girl may simply be perceived as very talkative and animated.

It is thought that women and people who are assigned female at birth (AFAB) are more likely to present with more emphasis on the inattentive aspects of ADHD (7). Often, this means that a young woman with ADHD may be more likely to daydream or be forgetful. This presentation of ADHD symptoms can be much less visibly disruptive, and so it is not picked up as a formal disorder of attention. As a result, it is often not until later in life when difficulties with organisation, time management and task completion become much more evident, that it is identified as a problem. 

If you or a loved one is diagnosed with ADHD, you’ll need to work together with your doctor or mental health professional to come up with the best treatment plan. It’s a complicated condition, generally best managed by a mixed treatment programme, which may include the following components:

Stimulants are the main kind of medication used in the treatment of ADHD. These are designed to help you concentrate better, be less impulsive, feel calmer and be able to function in the workplace and at home. A special authority is required to prescribe ADHD medication, so in order for someone to be prescribed stimulants, a formal diagnosis is needed.

Following diagnosis, a psychiatrist will apply for the special authority approval, and will likely work with you in the initial stages of trialling the medication they prescribe. As mentioned earlier, your psychiatrist will pass your medication information along to your GP with your permission, and your GP can continue to both monitor and prescribe your medication.

If you are prescribed medication, you are entitled to know:

• the names of the medicines
• what symptoms they are supposed to treat
• how long it will be before they take effect
• how long you will have to take them for and what their side effects are (short and long term)
• that you can stop taking medicines if you are experiencing negative side effects, on advice from your doctor
• that you can work with your GP and / or psychiatrist to change medicines if your current one is not working for you.

Currently, New Zealand regulations require someone with ADHD to renew their special authority every two years to keep getting access to their medication.

Talk-based therapies can look at your thinking, behaviour, relationships and environment, and provide you with additional support. This can be offered through mental health professionals such as counsellors, registered psychologists, clinical psychologists, psychotherapists, or occupational therapists.  

For ADHD, this includes self-regulation, teaching skills to help manage time and work towards goals, and teaching social skills to help support you at work and at home. 

Career counselling can also be a valuable tool in supporting those with ADHD.

Family counselling can play an important part in helping everyone in the family understand the condition and support you, provided the practitioner has good knowledge of ADHD. You can find ADHD-friendly practitioners online.

Any therapy/counselling should be provided in a manner that’s respectful of you and delivered in an environment where you feel comfortable and free to ask questions. It should be consistent with and incorporate your cultural beliefs and practices. If you have a poor experience with one counsellor, try not to let this deter you from working with another one who better meets your needs.

Thanks to Madeline Dykes, clinical psychologist, and members of the Thriving Madly peer support network in Christchurch for reviewing this content. Thank you to Claud Ibbotson, Sophie Jackson and Caryn Yachinta for updating this content. Date last reviewed: October, 2024.

Thanks also to Sutherland Self-Help Trust for making the 2022 updates possible.

1. Andersson, A., Tuvblad, C., Chen, Q., Rietz, E., Cortese, S., Kuja-Halkola, R., & Larsson, H. (2020). Research Review: The strength of the genetic overlap between ADHD and other psychiatric symptoms - a systematic review and meta-analysis.. Journal of child psychology and psychiatry, and allied disciplines. https://doi.org/10.1111/jcpp.13233 
2. Boedhoe, P., et al. (2020). Subcortical Brain Volume, Regional Cortical Thickness, and Cortical Surface Area Across Disorders: Findings From the ENIGMA ADHD, ASD, and OCD Working Groups.. The American journal of psychiatry, appiajp202019030331 . https://doi.org/10.1176/appi.ajp.2020.19030331 
3. Cheng, A., Illango, A., El-Kadi, A., Ma, H., Mitchell, N., Rajapakse, N., & Robb, C. (2022). Factors Impacting Gender Diagnostic Differences in ADHD: A Review. The Child Health Interdisciplinary Literature and Discovery Journal. https://doi.org/10.15173/child.v1i1.3126 
4. Miller, M., Musser, E., Young, G., Olson, B., Steiner, R., & Nigg, J. (2019). Sibling Recurrence Risk and Cross-aggregation of Attention-Deficit/Hyperactivity Disorder and Autism Spectrum Disorder. JAMA Pediatrics, 173, 147–152. https://doi.org/10.1001/jamapediatrics.2018.4076 
5. Saad, J., Griffiths, K., & Korgaonkar, M. (2020). A Systematic Review of Imaging Studies in the Combined and Inattentive Subtypes of Attention Deficit Hyperactivity Disorder. Frontiers in Integrative Neuroscience, 14. https://doi.org/10.3389/fnint.2020.00031 
6. Stibbe, T., Huang, J., Paucke, M., Ulke, C., & Strauss, M. (2020). Gender differences in adult ADHD: Cognitive function assessed by the test of attentional performance. PLoS ONE, 15. https://doi.org/10.1371/journal.pone.0240810 
7. Vildalen, V., Brevik, E., Haavik, J., & Lundervold, A. (2019). Females With ADHD Report More Severe Symptoms Than Males on the Adult ADHD Self-Report Scale. Journal of Attention Disorders, 23, 959 - 967. https://doi.org/10.1177/1087054716659362 
8. Yu, M., Gao, X., Niu, X., Zhang, M., Yang, Z., Han, S., Cheng, J., & Zhang, Y. (2023). Meta-analysis of structural and functional alterations of brain in patients with attention-deficit/hyperactivity disorder. Frontiers in Psychiatry, 13. https://doi.org/10.3389/fpsyt.2022.1070142