Attention-deficit hyperactivity disorder (ADHD) can be a complex disorder.

Mental illnesses can have a range of causes and sometimes seem to have no root “cause” at all.

Some mental health disorders and mental illnesses seem closely tied to genetics. These can be present in multiple members of the same family line. Other mental illnesses can be caused by trauma (either one traumatic event or ongoing trauma, such as abuse). Biological factors can also play a role. Chemical imbalances in the brain are often seen as a leading cause of many mental illnesses.

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What causes ADHD?

Some instances of mental illness can be caused by trauma or environmental factors. ADHD is not a disorder that develops over time. It is a lifelong condition in which a person’s brain is developing differently from birth. ADHD is not curable or something that a child will grow out of. Rather its symptoms can improve or worsen based on environment, sensory input, and treatment. While some may consider it possible to recover from a mental illness, ADHD can only be managed.

What are the symptoms of ADHD?

ADHD has many symptoms, and not all children or adults with ADHD will display every trait. For example, girls or women with ADHD are more likely to appear inattentive, whereas boys or men with ADHD are more likely to appear hyperactive. With that in mind, the main symptoms of ADHD are:

  • Inattentiveness (daydreaming)
  • Hyperactivity (restlessness)
  • Impulsivity and lack of planning
  • Issues with prioritization
  • Lack of focus or hyperfocus on preferred tasks
  • Inability or low ability to multitask
  • Bad time management
  • Difficulty working without time pressure
  • Becoming easily frustrated
  • Mood swings and temper issues
  • Jumping from task to task
  • Trouble with stress management

Is ADHD a mental illness?

Mental illness is a broad and encompassing term that can be used for those with ADHD. “Mental illness” discusses conditions that can impact how someone thinks, behaves, or feels. Therefore, there is a significant overlap between someone with ADHD and someone with a mental illness.

Since ADHD impacts thinking, behavior, and mood, it does meet the diagnostic criteria for mental illness. In reality, it is unlikely that many doctors will think of or refer to ADHD this way. ADHD is much more likely to be classed as a learning disability or simply as a neurodivergent disorder.

Why is ADHD not viewed as a mental illness?

In casual conversations or even diagnostic discussions, ADHD is not commonly referred to as a mental illness. Though, in technical terms, ADHD meets the criteria for mental illness, why do we not usually describe it as such?

ADHD can be managed and treated in a similar way to mental illness. It can also present similarly. And yet, a good reason doctors try to avoid the words “mental illness” or even “disorder” is the stigma attached to them. Another good reason is that this could lead to ADHD being misunderstood as a trauma-based disorder.

There is no shame in having either a mental illness or a neurodevelopmental disorder. These labels can be beneficial in finding the correct treatment and support. By separating ADHD from mental illness, some may feel less stigmatized. This can make them more likely to seek help, and it also helps those with comorbid disorders to define them and be treated for both.

ADHD, mental illness, and neurodivergence

As ADHD is a neurodivergence, it is worth considering the overlap between mental illness and neurodivergence. It is common for those with ADHD to suffer from comorbid mental health issues such as anxiety and depression. These can be caused by imbalances in brain chemistry but can also occur due to stress resulting from struggling in school, work, or life due to ADHD.

This can be especially common in undiagnosed individuals who have not been able to seek appropriate treatment. However, anyone with ADHD may have a higher risk. This is because of the frustration and stress of not feeling that you “measure up”, or that you are not capable of achieving in the same way as your peers. Over time, these feelings can lead to lifelong self-image issues that cause anxiety and worsen mood disorders such as depression.

In some cases, only one condition will be diagnosed, leading to improper treatment and worsening mental health. Those with neurodivergent conditions such as autism can also face these overlapping challenges.

How is ADHD treated?

ADHD can be diagnosed and treated effectively, as can many mental illnesses. However, as previously stated, the aim of ADHD treatment is not to “cure” children or adults. It is to help them manage this condition and live more easily. Not everyone opts for medication or finds that this works; other approaches can work well. Therapeutic intervention at school and home can be extremely beneficial for children with ADHD.

While ADHD can fall under the category of mental illness, it is better understood as a neurodevelopmental disorder. It can share characteristics with comorbid mental illnesses. Understanding what ADHD is and how it intersects with other disorders can be essential for knowing how to support those with ADHD best.