Methylphenidate is a stimulant drug that is authorised in children over six years of age as part of a comprehensive treatment programme for attention deficit hyperactivity disorder (ADHD). Treatment should be under the supervision of a specialist. Clinical trials submitted at the time of licensing have examined the safety and efficacy of methylphenidate in children with ADHD who received treatment for up to 12 months.
Since methylphenidate was first authorised in the United Kingdom, a range of representations regarding its safety profile have been received from Members of Parliament, patients and health care professionals. Some of these have specifically questioned the need for further research into its long-term safety profile but none have specifically provided information about the findings of new research.
It is recognised that there is limited information about the long term efficacy and safety profile of methylphenidate. This is reflected in the product information, which advises that treatment should be discontinued periodically to assess the child’s condition and that treatment should usually be discontinued during or after puberty.
Stimulants such as methylphenidate are known potentially to affect weight gain and growth in children following long-term use. The product information, for prescribers and patients/carers and the British National Formulary contain warnings about this risk and advise that the child's weight and height should be regularly checked throughout treatment. A number of studies have been conducted to examine this issue and these inform current clinical guidance which recommends regular monitoring and treatment breaks in children who are not gaining weight or growing as expected.
The longer term safety of the use of methylphenidate in routine clinical practice is closely monitored by the Medicines and Healthcare products Regulatory Agency (MHRA) in conjunction with other European regulatory authorities. There are currently ongoing discussions at European level on whether further formal studies are required to extend the knowledge about the safety profile of methylphenidate, including the long term safety profile. As new data emerge they are carefully evaluated by the MHRA and where necessary current prescribing advice is updated to reflect the new evidence.
(2) what estimate she has made of how many children (a) are diagnosed as having attention deficit hyperactivity disorder and (b) are receiving (i) prescribed medication, (ii) alternative treatments and (iii) a combination of such treatments.
We have received no representations about the breaching of National Institute for Health and Clinical Excellence (NICE) guidelines on the prescription of methylphenidate to children.
NICE recommended in March 2006 that drug treatment for attention deficit hyperactivity disorder (ADHD) should only be initiated by an appropriately qualified healthcare professional with expertise in ADHD and it should be based on a comprehensive assessment and diagnosis. Continued prescribing and monitoring of drug treatment may be performed by general practitioners, under shared care arrangements. Information on the number of prescriptions issued for methylphenidate in the community for children aged 0-15 years and those aged 16-18 years in full-time education is in the following table.
Information is not collected on the number of children diagnosed as having ADHD; nor how many are receiving (a) prescribed medication, (b) alternative treatments or (c) a combination of such treatments.
NICE has estimated that around five per cent of school-aged children meet the diagnostic criteria for ADHD, equivalent to 366,000 children and adolescents in England and Wales, but not all these children will require treatment.
England Number September 2001 to August 2002 215,000 September 2002 to August 2003 274,000 September 2003 to August 2004 320,000 September 2004 to August 2005 341,000 September 2005 to August 2006 384,000 Notes: 1. Data are for 0-15 year olds and those aged 16-18 in full time education. 2. Data cover prescriptions prescribed by general practitioners, nurses, pharmacists and others in England and dispensed in the community in the United Kingdom. Source: PACT Data
September 2001 to August 2002
September 2002 to August 2003
September 2003 to August 2004
September 2004 to August 2005
September 2005 to August 2006
1. Data are for 0-15 year olds and those aged 16-18 in full time education.
2. Data cover prescriptions prescribed by general practitioners, nurses, pharmacists and others in England and dispensed in the community in the United Kingdom.