Attention Deficit Hyperactivity Disorder (ADHD)

What is ADHD?

Attention deficit hyperactivity disorder (ADHD) is a behavioural disorder characterised by symptoms of inattention, impulsivity and hyperactivity.

What are the signs and symptoms of ADHD?

There are three core symptoms of ADHD. These are: inattention, hyperactivity and impulsivity. ADHD is categorised into one of three types, depending on the presence or absence of these symptoms:

  • Combined type with signs of hyperactivity/impulsivity and inattention
  • Predominantly inattentive type ADHD with inattention but not hyperactivity/impulsivity
  • Predominantly hyperactive-impulsive type ADHD with hyperactivity/impulsivity but not inattention

The symptoms associated with ADHD may appear in different ways at different ages; the hyperactivity of childhood may present as excessive fidgetiness in adolescence and mature into a sustained inner sense of restlessness in adult life. Inattention may decrease, as attention span usually increases with age.

What are the causes of ADHD?

The exact cause of ADHD is unknown. However, it is known to ‘run in families’ and progress is being made in identifying the genetic components involved.

It is also possible that ADHD may result from environmental factors - things that are in the world around us. Cigarette smoking during pregnancy and drinking alcohol during early pregnancy may be associated with ADHD.

Who is likely to be at risk of ADHD?

At present, ADHD affects about 5.29% of the world’s population*. As the illness can often result in disruptive behaviour in the classroom, it is often first identified at school.

Although ADHD is generally considered a childhood disorder, it is now known that approximately two thirds of children affected with ADHD symptoms can carry the condition into adolescence and then adulthood.

*Using DSM-IV criteria

How is ADHD diagnosed?

ADHD is not an easy disorder to diagnose, so the diagnosis should only be made by a specialist psychiatrist, or other appropriately qualified healthcare professional with the right training and expertise.

This is because there are other conditions which are very similar to ADHD that have to be ruled out and because ADHD often occurs alongside other conditions.

The diagnosis is based on:

  • A full clinical and psychosocial assessment
  • A full developmental and psychiatric history
  • Reports from observers (such as school or place of work) and an assessment of an individual’s mental state

What are the treatments for ADHD?

Treating ADHD usually involves behavioural therapy, medication, or a combination of behavioural therapy and medication.

Further information on ADHD can be found at: