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Fake Dictionary, definition of the word ADHD.


What is ADHD?

Attention Deficit Hyperactivity Disorder (ADHD) is a condition that can affect children and adults but it most commonly diagnosed when children are between 6 and 12 years old.  ADHD refers to certain behaviours that are displayed, including hyperactivity, inattentiveness and impulsiveness.  Supplementary issues may include anxiety or sleep disorders.1

ADHD often improves with age and is a condition that can be managed with various techniques and medication if required.  It is more common in boys than in girls.2  It is important to remember that most children display signs of hyperactivity or other ADHD symptoms at certain times during their life – this does not mean they have ADHD.  ADHD would require a proper diagnosis of symptoms from a doctor or clinician.

What causes ADHD?

The exact cause of ADHD is still not fully known or understood.  It is not a brain disease, it is a dysfunction of the brain.  ADHD does tend to show a hereditary pattern suggesting a genetic connection.  There could be connections to brain differences or how certain chemicals work within the brain.2

Research shows that approximately 60-80 per cent of children suffering from ADHD will have at least one other medical condition, including conditions such as dyslexia or dyspraxia.2

Other factors that have been connected to the cause of ADHD include smoking, alcohol or drug abuse during pregnancy, premature birth and low birth weight.  Statistics show that around 2-5 per cent of school-aged children are thought to have ADHD.1

What are the symptoms of ADHD?

Symptoms of ADHD seem to be different in children to those in adults.  In children, the symptoms seem to be of inattentiveness and hyperactivity and impulsiveness including:3

    • having a short attention span and being easily distracted

    • making careless mistakes – for example, in schoolwork

    • appearing forgetful or losing things

    • being unable to stick at tasks that are tedious or time-consuming

    • appearing to be unable to listen to or carry out instructions

    • constantly changing activity or task

    • having difficulty organising tasks

    • being unable to sit still, especially in calm or quiet surroundings

    • constantly fidgeting

    • being unable to concentrate on tasks

    • excessive physical movement

    • excessive talking

    • being unable to wait their turn

    • acting without thinking

    • interrupting conversations

    • little or no sense of danger

Symptoms can change over time and therefore when the child is an adult some symptoms can remain such as depression or dyslexia.  15% of children will still continue to have all symptoms as an adult but 65% will only have a few symptoms remaining.

Symptoms in adults tend to be more subtle: 3

    • carelessness and lack of attention to detail

    • continually starting new tasks before finishing old ones

    • poor organisational skills

    • inability to focus or prioritise

    • continually losing or misplacing things

    • forgetfulness

    • restlessness and edginess

    • difficulty keeping quiet and speaking out of turn

    • mood swings, irritability and a quick temper

    • inability to deal with stress

    • extreme impatience

    • taking risks in activities, often with little or no regard for personal safety or the safety of others – for example, driving dangerously

It is important to obtain a professional medical diagnosis to confirm ADHD.


Testing would be carried out by a specialist healthcare professional such as a paediatrician or clinical psychologist.  There isn’t a specific test that can be carried out to confirm ADHD but a thorough assessment would be done to establish the medical history and a full picture of the patient’s symptoms.  Observations and questionnaires may also be part of the diagnosis process.


Medication is available to treat ADHD but there are other techniques and ways to help ADHD sufferers that don’t involve medication.  The medications used for ADHD all have side effects but the benefits and harms should be discussed with the clinician.

Medications would need to be prescribed and monitored by a doctor or specialist including 4

    • methylphenidate (brand name Ritalin®)

    • dexamfetamine

    • lisdexamfetamine

    • atomoxetine

    • guanfacine

Other techniques include: 4

    • psychoeducation

    • behaviour therapy

    • parent training and education programmes

    • social skills training

    • cognitive behavioural therapy (CBT)

    • looking at diet

    • supplements

There is some evidence suggesting that ADHD and thyroid abnormalities are linked. Many children suffering from ADHD show generalised resistance to thyroid hormone.5–7

There are certain similarities between the symptoms presented with ADHD and those displayed with a thyroid disorder. Brain chemical changes that are caused by a thyroid issue can affect the symptoms of ADHD. The chemical imbalances cause the body not to function as it should subsequently sending mixed signals to the brain. This confusion in signals can impact symptoms already present due to ADHD 8 and may possibly worsen them.

There isn’t currently any evidence that confirms one disorder directly causes the other or increases your chances of suffering from the second illness. It is clear that further research into any connections is required.

For more support check out our online community:


  1. NHS. Overview – Attention deficit hyperactivity disorder (ADHD). NHS. Published May 30, 2018.
  2. The Child and Adolescent Mental Health Service in collaboration with the Child and Family Information Group. Attention deficit hyperactivity disorder (ADHD). Great Ormond Street Hospital for Children. Published October 2016.
  3. NHS. Symptoms – Attention deficit hyperactivity disorder (ADHD). NHS. Published May 30, 2018.
  4. NHS. Treatment – Attention deficit hyperactivity disorder (ADHD). NHS. Published May 30, 2018.
  5. Hauser P, Zametkin AJ, Martinez P, et al. Attention Deficit-Hyperactivity Disorder in People with Generalized Resistance to Thyroid Hormone. N Engl J Med. Published online April 8, 1993:997-1001. doi:10.1056/nejm199304083281403
  6. Weiss RE, Stein MA, Trommer B, Refetoff S. Attention-deficit hyperactivity disorder and thyroid function. The Journal of Pediatrics. Published online October 1993:539-545. doi:10.1016/s0022-3476(05)80947-3
  7. Hauser P, McMillin JM, Bhatara VS. Resistance To Thyroid Hormone: Implications for Neurodevelopmental Research On the Effects of Thyroid Hormone Disruptors. Toxicol Ind Health. Published online January 1998:85-101. doi:10.1177/074823379801400108
  8. Álvarez-Pedrerol M, Ribas-Fitó N, Torrent M, Julvez J, Ferrer C, Sunyer J. TSH concentration within the normal range is associated with cognitive function and ADHD symptoms in healthy preschoolers. Clin Endocrinol. Published online June 2007:890-898. doi:10.1111/j.1365-2265.2007.02871.x

Date updated: 22.03.21 (V1.3)
Review date: 11.10.21

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