Starting on medication for ADHD

Starting stimulant medication -key learning points

  • Methylphenidate is the first choice stimulant in the UK
  • Treatment with stimulants should only be initiated by a child and adolescent psychiatrists or paediatrician with expertise in ADHD but continued prescribing and monitoring may be performed by general practitioners under shared care arrangements with specialists.
  • Clinicians should measure and record child's height, weight, blood pressure and pulse as a baseline prior to starting any medication for ADHD
  • The usual starting dose of immediate release methylphenidate is 5mg mane in primary aged children and 5mg bd in secondary aged children. This should be titrated upwards to a maximum of 20mg per dose according to response and side effects to allow optimal dose to be established. The usual maximum dose is 60mg per day.
  • Involvement of school teachers in the titration process is crucial
  • Single drug treatment should be initiated first. If side effects intolerable or drug is ineffective, an alternative single drug should be tried before combinations of drugs are used.

Only a child and adolescent psychiatrist or a paediatrician with special training in ADHD should initiate pharmacological treatment for children with a diagnosis of ADHD. The American Academy of Child and Adolescent Psychiatry have published a practice parameter for the assessment and treatment of children and adolescents with Attention-Deficit/Hyperactivity Disorder (2007) which gives up to date recommendations on the pharmacological management of ADHD. Additional information relevant to UK practitioners will soon be available from the National Institute for Health and Clinical Excellence who are in the process producing guidance for the assessment and management of ADHD (see www.nice.org.uk for drafts out to consultation).

Starting stimulant medication

Stimulant medication does not address the condition in isolation from other treatment approaches and, in the UK, is generally only considered after other approaches have been tried. Medication aims to minimise core symptoms and to improve the effectiveness of other interventions. Stimulant medications are only licensed for children over 6 years of age as 'part of a comprehensive treatment programme for attention deficit hyperactivity disorder when remedial measures alone prove insufficient (under specialist supervision) (BNF, p206, Sept 2004). The aim of a trial of stimulant medication should be to determine the lowest effective dose which produces the maximum therapeutic effect whilst keeping side effects to a minimum. In the UK methylphenidate is usually the first choice of stimulant to be trialed.

“The information below on the use of stimulant medication should be read in conjunction with the National Institute for Health and Clinical Excellence’s National Institute for Health and Clinical Excellence Review of technology Appraisal 13- methylphenidate, atomoxetine and dexamphetamine for attention deficit hyperactivity disorder (ADHD) in children and adolescents available via www.nice.org.uk/TA098.  

See also “Information for children and adolescents with attention deficit hyperactivity disorder, their families and the public” available from www.nice.org.uk/TA098publicinfo”

Further description on the four main protocols for the clinical usage of methylphenidate can be found via http://www.rcpsych.ac.uk/traindev/cpd/adhd/drug/mpd14b.htm

1. Prior to the commencement of any medication, parents and young people should be given full written details of the medication, including details of its benefits, limitations and potential side effects. This should be given in a form that the parents and young people can understand and there must be opportunity to reflect on this and to ask questions before starting treatment. See downloads for examples of information sheets which can be given to parents of primary and secondary school aged children summarizing side effects and titration regime. Information for children and adolescents with attention deficit hyperactivity disorder, their families and the public” is available from www.nice.org.uk/TA098publicinfo

2. Prior to the commencement of any medication, full details of height, weight, blood pressure and pulse should be entered in the child's health record. In line with drug company recommendations, some local services also suggest a baseline full blood count is performed. Unfortunately, there is currently a diversity of opinion in the UK as to whether baseline (and follow up) full blood counts should be routinely performed on all children prescribed stimulant medications. The European clinical guidelines for hyperkinetic disorder - first upgrade (Taylor et al, 2004, p.1/16) do not recommend routine blood tests and state that "the remote chance of benefit is usually outweighed by the unpleasantness for the child". Full blood counts should only be performed where there a clinical indication (i.e. the child is symptomatic).

3. The trial of stimulant medication should follow the protocol in line with that recommended by Peter Hill and Eric Taylor outlined in the Royal College Psychiatrist's book Focus on the Use of Stimulants in Children with Attention Deficit Hyperactivity Disorde" (Joughin and Zwi, 1999). This in line with the recommendations coming out the MTA trial. Information on titration procedures is also contained in Hill and Taylor's (2001) 'Auditable protocol for treating attention deficit/hyperactivity disorder'. (Available in full text form on line via http://adc.bmjjournals.com/).This web address takes you to the home page. Enter Hill in the author box and ADHD in the keywords box and this will lead you to the article).

4. In general it is advised to titrate stimulant medication against adverse and desirable effects rather than give on a predetermined mg/kg basis (see below). The usual starting dose of immediate release methylphenidate is 5mg mane in primary aged children and 5mg bd in secondary aged children. This should be titrated upwards to a maximum of 20mg per dose according to response and side effects to allow optimal dose to be established. By using a fixed-dose titration trial, similar to that used in the MTA trial, the child will try each of 4 doses i.e. 5mg, 10mg, 15mg and 20mg and a decision can then be made as to the dose which yields the maximum benefit to the child balanced against any side effects occurring. In smaller children the clinician might choose to miss out the highest doses depending on the response seen and the emergence of side effects.

The recommended starting dose of dexamphetamine is 2.5mg mane or BD. Titration upwards occurs in a similar manner as with methylphenidate. Usual maximum dose of dexamphetamine prescribed is 10mg three times a day.

5. Where methylphenidate is prescribed on a mg/kg basis an appropriate starting dose would be in the region of 0.2mg/kg per dose. The ceiling dose would be 0.7mg/kg/dose, less if beneficial effects are seen before this point or adverse side effects occur.

6. Children weighing less than 25kg generally should not receive single doses greater than 15mg of methylphenidate or 10mg of dexamphetamine (Greenhill et al, 2001). According to the Summary of the American Academy of Child and Adolescent Psychiatry's practice parameter for the use of stimulant medications in the treatment of children, adolescents and adults (Greenhill et al, 2001, p.1355), expert consensus is that occasionally doses of stimulants may go above recommended licensed limits. Experts in the USA often limit the upper range to a total daily dose of 40mg of dexamphetamine or 25mg for a single dose of methylphenidate when methylphenidate is given in multiple doses throughout the day. In general, clinicians should stick within BNF limits and should consider seeking advice from a tertiary centre before prescribing higher levels.

7. The frequency of dosing will be determined on an individual basis. Many children and young people take psychostimulants three times daily, thereby offering treatment in the after school period, thus providing cover for homework or after school activities. Pharmacodynamic studies suggest that stimulant blood levels need to increase throughout the day to maintain constant efficacy. This is because short-term tolerance to methylphenidate develops by the second dose given in the same day (Swanson et al, 1999).

8. OROS methylphenidate (Concerta XL) can be used from the start of therapy with an initial dose of 18mg daily increased at intervals of 1 week up to 54mg daily. In practice a number of UK clinicians will prescribe to a maximum of 72mg daily. For Equasym XL, the initial starting dose is 10mg before breakfast. N.B. it is probably easier to titrate the correct dose of methylphenidate for an individual child by using immediate release methylphenidate in the initial trial phase and then converting to modified release methylphenidate at a later point in those children and young people for whom it is thought that a once daily formulation might be beneficial.

9. Parental consent should be sought to notify the Head Teacher/ SENCO/ Head of Year of a child's particular school as well as LEA support staff who are involved at the start of a trial stimulant medication.

10. Contact (either by telephone or by questionnaire) should be made by the prescribing doctor with the child's parents and school within the first 2 weeks of commencing medication and thereafter at regular intervals over the next 4-8 weeks to enable the doctor to titrate the dosage according to the response. Subsequent outpatient follow-ups should take place at approximately one month, 3 months, 6 months and 12 months (or more frequently if there is a clinical indication).

11. Medication side effects should be specifically enquired about at each dose change and subsequent clinic visits.

12. Feedback from the child's school before each appointment should be sought (with parental permission). Involvement of the child's school teachers in the titration (and subsequent monitoring process) is crucial in assessing response to treatment. (See section on monitoring of medication for further information. See also downloads for example of letter to school requesting feedback prior to ADHD follow up clinic appointment).

13. It is not necessary for stimulant medication to be taken 7 days a week where the aim is for symptom control in school time only. In such instances a 5 day a week schedule with breaks at the weekend and in school holidays may be appropriate.

14. Once stabilised on medication, where is local agreement, the child's GP should be notified in order to for him/her to continue prescribing in liaison with the specialist CAMHS/paediatric ADHD clinic. In many areas a shared care protocol will have been drawn up. An example of such a protocol is available on the SIGN website (http://www.sign.ac.uk/guidelines/fulltext/52/index.html) -click on 'supporting material for guideline').

15. If no benefit after an adequate trial of one stimulant [e.g. up to a maximum of 20mg per dose of methylphenidate (60mg per day), or 10mg per dose of dexamphetamine], consider trying an alternative stimulant.

16. If no response to alternative medication, review the diagnosis and consider referral to a tertiary centre.

Starting Atomoxetine

For children and adolescents up to 70kg in body weight, the dose of atomoxetine is based on weight. The approximate starting dose is 0.5mg/kg/day for a minimum of 7 days. The recommended maintenance dose is 1.2mg/kg/day. For those over 70kg, Atomoxetine should be initiated at a dose of 40mg daily, the usual recommended maintenance dose is 80mg and the maximum recommended total daily dose is 100mg. Patients weighing up to 55kg can be treated with one tablet daily but individuals weighing more than this would require two tablets, doubling the treatment cost. The onset of efficacy with atomoxetine is very different to stimulant drugs. Although some symptom relief may be seen by one week, near maximum benefits are usually only seen after 4 weeks and onwards. Atomoxetine should be taken every day and drug holidays avoided.

Calculating the correct dose of Atomoxetine

For children and adolescents less than 70kg body weight

0.5mg/kg/day

1.2mg/kg/day

1.4mg/kg/day or 100mg (which ever is less)

Approximate starting dose (minimum of 7 days)

Daily target dose

Maximum total daily dose evaluated for safety(after an additional 2-4 weeks)

For children and adolescents over 70kg body weight

Approximate starting dose is 40mg (taken for a minimum of 7 days)

Daily target dose is 80mg /day

Maximum total daily dose evaluated for safety
(after an additional 2-4 weeks) is 100mg

 

When starting Atomoxetine: Remind child and parents/care givers

  • Onset is not immediate. 4-6 weeks are required to approach maximal efficacy, although some improvement may be seen by the end of the first week.
  • Atomoxetine should be taken every day drug holidays avoided
  • Side effects include: somnolence, loss of appetite, nausea, vomiting, irritability or agitation, increased risk of suicidal thoughts and behaviour and a risk of rare hepatic disorders.
  • Side effects may occur with treatment initiation but they are usually only mild-moderate and subside with continued treatment.
  • Atomoxetine can be taken with or without food.

Starting Tricyclic Antidepressants

There is no consensus regarding dose recommendations for TCA's. When starting TCA's baseline measurements of BP, pulse, cardiovascular examination and ECG should be undertaken.

The trial of a TCA such as imipramine should follow the titration procedure recommended by Peter Hill and Eric Taylor outlined in the Royal College Psychiatrist book Focus on the Use of Stimulants in Children with Attention Deficit Hyperactivity Disorder (Joughin and Zwi, 1999). Information is also contained in the 'Auditable protocol for treating attention deficit/hyperactivity disorder'. P. Hill and E.Taylor. Archives of Disease in Childhood, 84, Page 408. (Available in full text form on line via http://adc.bmjjournals.com/ This web address takes you to the home page. Enter Hill in the author box and ADHD in the keywords box and this will lead you to the article).

For additional information on TCA's, consult the SIGN guidelines (2001) (http://www.sign.ac.uk/guidelines/fulltext/52/index.html- click on section 5 pharmacological therapy and see page 5). This recommends commencing with a low (subtherapeutic) divided dose of imipramine or amitriptyline (10-25mg/day) or nortriptyline (5-10mg/day) and warning about potential side effects. The dose should then be titrated upwards at intervals of several days while monitoring side effects. The target dose is 1-2mg/kg/day for impramine and amitriptyline and 0.5mg-1mg for nortryptyline.

N.B. when stopping TCA's slow withdrawal is recommended to prevent cholinergic rebound.

Starting Clonidine

Before starting clonidine take a medical history from the patient and first degree relatives. A history of sudden death, repeated fainting or arrhythmias in family members would probably rule out it's use. The dose of clonidine should be built up gradually over 2-4 weeks. The dose range is 3-5 microgrames/kg/day divided into 2 doses. It takes 6 weeks on full dose before optimum benefit might be seen. N.B. when stopping clonidine, the medication should be slowly tappered down and not withdrawn suddenly due to the risk of rebound hypertension and tics.

Useful web based sources of information on starting medications for children with ADHD