Attention deficit hyperactivity disorder (ADHD)

F90.0-F90.9

DESCRIPTION

Children with ADHD display developmentally inappropriate degrees of inattention, impulsiveness and hyperactivity that interfere with their functioning.

DIAGNOSTIC CRITERIA (DSM 5)

May be mild, moderate or severe:

  • predominantly inattentive
  • predominantly hyperactive-impulsive, and
  • combined

Inattention: (9 symptoms)

  • Failing to give close attention to details or making careless mistakes.
  • Having difficulty sustaining attention in tasks or play.
  • Not listening when spoken to directly.
  • Failing to complete tasks or follow through on instructions.
  • Often losing things for tasks or activities.
  • Often having difficulty organising tasks and activities.
  • Being forgetful in daily activities.
  • Being easily distracted by extraneous stimuli.
  • Avoiding or being reluctant to engage in tasks requiring sustained mental effort.

Hyperactivity: (6 symptoms)

  • Often fidgeting, squirming or tapping.
  • Leaving his/her seat.
  • Running or climbing inappropriately.
  • Is “on the go”, or behaves as if “driven by a motor”.
  • Is unable to play quietly.
  • Talking excessively.

Impulsivity: (3 symptoms)

  • Blurts out answers.
  • Has difficulty waiting his/her turn.
  • Interrupts or intrudes on others.

  • Onset of several symptoms before 12 years.
  • Requires 6 symptoms of inattention or hyperactivity/impulsivity.
  • Symptoms have persisted for 6 months to a degree inconsistent with their developmental level.
  • Symptoms present in two or more settings.
  • Interferes with or reduces the quality of social, academic or occupational functioning.
  • Exclude psychotic or other psychiatric disorders.

Note:

  • Common co-morbid conditions include oppositional defiant disorder, conduct disorder, depression (particularly in girls) and substance use disorders (SUDs), as well as HIV and epilepsy.
  • Certain conditions may ‘mimic’ ADHD such as, developmental disorders, motor coordination problems, intellectual disability, post-traumatic and post infectious encephalopathy as well as anxiety and mood disorders.
  • Girls may more commonly present with inattentive-type ADHD. The diagnosis may therefore be missed.

GENERAL AND SUPPORTIVE MEASURES

Identify and treat co-morbidities such as depressive disorders early, as this may prevent the onset of substance misuse (to ‘self-medicate’) and other risk-taking behaviours during adolescence.

  • Parent counselling:
    • rules and limit-setting
    • positive reinforcement of pro-social behaviour
    • consistent routine
    • restrictive diets and OTC medications are of no proven value
  • Behaviour-based interventions:
    • reward positive behaviour
    • improve social awareness and adjustment
  • Social skills groups.
  • Identify learning difficulties and refer to educational support services.

MEDICATION TREATMENT

For children under the age of six years:

Refer for diagnostic assessment by a child and adolescent psychiatrist or paediatrician.

For children over the age of six years:

Initiate treatment using the short-acting methylphenidate formulation until effective dosage achieved. Reduce the dose or withdraw methylphenidate if a paradoxical increase in symptoms occurs.

  • Methylphenidate, short-acting, oral, 1 mg/kg/day.
    • Initial dose: 5 mg, 2–3 times daily, at breakfast, lunch and no later than 14h30 (approximately every 3 to 3½ hours).
    • Increase the dose at weekly intervals by 5–10 mg until symptoms are controlled. Use the lowest effective dose.
    • Maximum daily dose: 60 mg (adult dose). Any dose greater than 60 mg/day should be prescribed by a child psychiatrist or paediatrician.

Contraindications to methylphenidate

Absolute:

  • Hyperthyroidism
  • Glaucoma
  • Concomitant mono-amine oxidase inhibitor therapy
  • No absolute contraindication to the concomitant use of methylphenidate with antiepileptic drugs (AEDs) or antiretroviral therapy (ART). However, exercise caution with the prescribed dosages, be aware of potential drug-drug interactions and monitor for adverse effects.

Relative:

  • Hypertension
  • Cardiac abnormality – need ECG and cardiology assessment
  • Anxiety
  • Agitation
  • Epilepsy
  • Tics

Discontinuation of treatment

  • If no objective improvement of symptoms has been observed e.g. using an ADHD Rating Scale, after appropriate dosage adjustments over a two-month period.
  • To establish whether on-going treatment is indicated in a child on long-term stimulant therapy, trial periods off treatment should be part of the management plan.
  • Indications for a trial off treatment:
    • treatment duration in excess of 2-3 years,
    • adolescent age (particularly late adolescence), and
    • a substantial reduction in core ADHD symptoms, evident in more than one setting.
  • Trials off treatment should be planned at times least disruptive to the child’s academic and social functioning i.e. time the treatment withdrawal outside of major commitments such as examinations.
  • Duration of treatment withdrawal can be for one week to a month, depending on whether stability is maintained.
  • Treatment can be withdrawn abruptly, with no need to taper dosages.
  • Obtain feedback from teachers and parents (verbal feedback, completion of parent and teacher ADHD rating scales), before and during the trial off treatment.
  • Assess the child and document the mental state (symptoms of ADHD), before and during the trial off treatment.
  • Monitor 3 monthly for one year.
  • Re-initiate treatment (at last dosage prescribed), if:
    • there is a significant re-emergence of symptoms after one week off treatment and/or during the month off medication, or
    • after a longer trial off medication, e.g. at 3 monthly follow up visits, there is evidence of symptom re-emergence.

Note:
Adolescents are more likely to present with poor concentration, inattentiveness or impulsivity, rather than hyperactivity.

  • Hyperactivity symptoms usually decrease but inattention symptoms may persist during adolescence.
  • Remission is achieved in 30% of patients during adolescence.

REFERRAL

  • No response to treatment after 8 weeks.
  • Presence of comorbid psychiatric conditions with severe functional impairment: oppositional defiant disorder, mood disorders, anxiety disorders, debilitating tics.
  • Presence of uncontrollable seizures.
  • HIV infected status.