Regardless of the age at which it appears, ADHD causes problems with attention, hyperactivity, or impulsivity. However, this syndrome can manifest itself differently in children and adults.


In adults, ADHD symptoms may include restlessness or a feeling of inner tension, inability to finish tasks on time, disorganisation in everyday life, difficulty staying focused on tasks or conversations, a tendency to lose important objects, a tendency to try to do several things at the same time, searching for quick solutions to problems, and difficulty maintaining a job or relationships.


A late diagnosis of ADHD can occur for several reasons:

  • ADHD is difficult to detect, especially when the predominant symptom is inattention. Parents or teachers may have difficulty recognising the illness and referring the child for evaluation. Additionally, healthcare professionals may mistakenly confuse ADHD with other illnesses, such as anxiety or depression. Sometimes an adult only realizes that their diagnosis was not made correctly in the past when they discover that one of their children is diagnosed with ADHD and identify their symptoms in their child.
  • In some children, ADHD symptoms are mild and do not have a relevant negative impact, so making a diagnosis is not justified. Although ADHD symptoms usually tend to decrease in intensity with age, in some people, the symptoms worsen in adulthood, and only then does the diagnosis become evident.
  • Several factors can mask the symptoms of ADHD during childhood and minimise their negative impact on the child's daily life. For example, a child with ADHD can achieve good school results because they have a structured and protective family environment. In these cases, ADHD symptoms may only become evident at a stage in life when the person is more autonomous (e.g., when entering higher education).
  • In adulthood, the combination of professional, family, and social responsibilities puts levels of concentration, planning, organisation, and the ability to carry out daily tasks to the test. For an adult with undiagnosed ADHD, these demands are especially difficult to manage, causing high levels of stress, anxiety and depression. It is often only at this stage when symptoms of “exhaustion” or physical and mental exhaustion predominate that the adult recognises that they need help.


Adults with untreated ADHD have more difficulty achieving their academic or career goals and maintaining stable relationships with others. Procrastination, impulsivity, and difficulty managing time and tasks often create problems in relationships with others and harm the work and family environment. Consequently, adults with untreated ADHD often have low self-esteem and often suffer from depression, anxiety, or substance use.


ADHD is a neurodevelopmental disorder that affects how various regions of the brain communicate with each other. Although there is no cure for ADHD, available treatments are very effective in reducing symptoms. Treatment usually includes medications to stimulate the brain and psychological strategies that minimise symptoms.


For more information please contact HPA on (+351) 282 420 400.