Attention deficit hyperactivity disorder (ADHD)

Attention deficit hyperactivity disorder (ADHD) describes behavioural symptoms which affect about two to five per cent of school-age children. ADHD affects boys more often than girls.


Most children are diagnosed when they're between six and twelve years old. ADHD can become more noticeable when a child's circumstances change, such as when they start school. 

ADHD symptoms include:

  • having a short attention span
  • being easily distracted
  • appearing forgetful or not seeming to listen
  • being disorganised
  • taking a long time to do something and rarely finishing what they start
  • being restless, fidgeting or being overactive
  • being impulsive and doing things without thinking

ADHD can occur in people of any intellectual ability, although it is more common in people with learning difficulties. People with ADHD may also have additional problems, such as sleep and anxiety disorders.

ADHD is not the same as the usual active behaviour of a child - it’s normal for young children to get bored, restless or inattentive at times and to want to try new activities. ADHD is an extreme of normal child behaviour. If you are concerned about your child’s behaviour or health, you should tell your doctor your concerns.

The symptoms of ADHD usually improve with age, but many adults who are diagnosed with the condition at a young age will continue to experience problems.

Causes of ADHD

The exact cause of ADHD is unknown but the condition has been shown to run in families. 

Other factors that have been suggested as potentially having a role in ADHD include:

  • being born prematurely (before the 37th week of pregnancy)
  • having a low birthweight
  • smoking, alcohol or drug abuse during pregnancy


If the doctor thinks your child has ADHD, they may refer them to a specialist. Your child will have different interviews. The specialist may want to speak to you and to your child’s teachers. If your child is diagnosed with ADHD, they will be offered treatment:

  • medication
  • behavioural therapy

Living with ADHD

If your child has ADHD, it is important to remember that they cannot help their behaviour.

Treatment for ADHD might help you and your child with day-to-day tasks including:

  • getting to sleep at night
  • getting  ready for school on time
  • listening to and carrying out instructions
  • being organised
  • behaviour at social occasions
  • behaviour during shopping

Adults with ADHD may also find they have similar problems, and some may have issues with drugs, crime and employment.


The information on this page was provided by the Department of Health.

For further information please see terms and conditions.

This page was reviewed April 2018

This page is due for review August 2019

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