What is ADHD?

Attention deficit hyperactivity disorder (ADHD) is a psychiatric disorder or neurobehavioral disorder characterized by significant difficulties either of inattention or hyperactivity and impulsiveness or a combination of the two. According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR), symptoms emerge before seven years of age.


Signs and Symptoms

Children with ADHD tend to get distracted from schoolwork rather easily, and they often behave disruptively.

Inattention, hyperactivity, disruptive behaviour and impulsivity are common in ADHD.  Academic difficulties are also frequent.  The symptoms are especially difficult to define because it is hard to draw a line at where normal levels of inattention, hyperactivity, and impulsivity end and clinically significant levels requiring intervention begin.  To be diagnosed with ADHD, symptoms must be observed in two different settings for six months or more and to a degree that is greater than other children of the same age.

The symptom categories yield three potential classifications of ADHD — predominantly inattentive type, predominantly hyperactive-impulsive type, or combined type if criteria for both subtypes are met:

Predominantly inattentive type symptoms may include:

  • Be easily distracted, miss details, forget things, and frequently switch from one activity to another
  • Have difficulty maintaining focus on one task
  • Become bored with a task after only a few minutes, unless doing something enjoyable
  • Have difficulty focusing attention on organizing and completing a task or learning something new or trouble completing or turning in homework assignments, often losing things (e.g., pencils, toys, assignments) needed to complete tasks or activities
  • Not seem to listen when spoken to
  • Daydream, become easily confused, and move slowly
  • Have difficulty processing information as quickly and accurately as others
  • Struggle to follow instructions.

Predominantly hyperactive-impulsive type symptoms may include:

  • Fidget and squirm in their seats
  • Talk nonstop
  • Dash around, touching or playing with anything and everything in sight
  • Have trouble sitting still during dinner, school, and story time
  • Be constantly in motion
  • Have difficulty doing quiet tasks or activities

and also these manifestations primarily of impulsivity:

  • Be very impatient
  • Blurt out inappropriate comments, show their emotions without restraint, and act without regard for consequences
  • Have difficulty waiting for things they want or waiting their turns in games

Some children, adolescents, and adults with ADHD have an increased risk of experiencing difficulties with social skills, such as social interaction and forming and maintaining friendships.  About half of children and adolescents with ADHD experience rejection by their peers compared to 10-15 percent of non-ADHD children and adolescents. Training in social skills, behavioural modification and medication may have some limited beneficial effects.

The most important factor in reducing emergence of later psychopathology, such as major depression, criminality, school failure, and substance use disorders is formation of friendships with people who are not involved in delinquent activities.  Adolescents with ADHD are more likely to have difficulty making and keeping friends due to impairments in processing verbal and nonverbal language.

Handwriting difficulties seem to be common in children with ADHD.  Delays in speech and language as well as motor development occur more commonly in the ADHD population.


The management of ADHD involves either psychotherapy or medication therapy alone or a combination of the two.  Medications used in the treatment of ADHD include stimulants, noradrenergic agents, adrenergic agonists and certain antidepressants. Medications have at least some effect in about 80% of people.  Dietary modifications may also be of benefit.


The evidence is strong for the effectiveness of behavioural treatments in ADHD.  It is recommended first line in those who have mild symptoms and in preschool-aged children.  Psychological therapies used include psychoeducational input, behavior therapy, cognitive behavioral therapy (CBT), interpersonal psychotherapy (IPT), family therapy, school-based interventions, social skills training, parent management training, neurofeedback, and outdoor activities.  Parent training and education have been found to have short-term benefits.  There is a deficiency of good research on the effectiveness of family therapy for ADHD, but the evidence that exists shows that it is comparable in effectiveness to treatment as usual in the community and is superior to medication placebo.  Several ADHD specific support groups exist as informational sources and to help families cope with challenges associated with dealing with ADHD.


Stimulant medications are the medical treatment of choice.  There are a number of non-stimulant medications, such as atomoxetine, that may be used as alternatives.  There are no good studies of comparative effectiveness between various medications, and there is a lack of evidence on their effects on academic performance and social behaviours.  While stimulants and atomoxetine are generally safe, there are side-effects and contraindications to their use.  Medications are not recommended for preschool children, as their long-term effects in such young people are unknown.  Research into the long-term effects of stimulants in ADHD have come to conflicting conclusions with one study finding benefit, another finding no benefit while another finding evidence of harm.  The current research has methodological problems and more robust research has been recommended. Any drug used for ADHD may have adverse drug reactions such as psychosis and mania, though methylphenidate-induced psychosis is uncommon.  Regular monitoring of individuals receiving long-term stimulant therapy for possible treatment emergent psychosis has been recommended.  Stimulant therapy is recommended to be discontinued periodically during protracted therapy to assess for continuing need for medication.  Tolerance to the therapeutic effects of stimulants can occur, with rebound effects occurring when the dose wears off. Therefore due to the risk of discontinuation/rebound effects abrupt withdrawal of stimulants is not recommended.

People with ADHD have an increased risk of substance abuse, and research studies have found that stimulant medications reduce this risk or have no effect on substance abuse.  Additionally, stimulant medications approved for treating ADHD have the potential for abuse and dependence.  Atomoxetine due to its lack of abuse potential may be preferred in individuals who are at risk of abusing stimulant medication.

Deficiency in zinc has been associated with inattentive symptoms of ADHD and there is evidence that zinc supplementation can benefit ADHD children who have low zinc levels.  There is also some evidence that zinc supplementation leads to a significant reduction in the dosage of stimulants required for ADHD.

(Obtained from the Web)