Evidence lacking for most common ADHD drug
ADHD in kids is most often medicated with methylphenidate (Ritalin®, Concerta®), but a comprehensive Cochrane Review finds there is little evidence showing that it really benefits. Because of the potential for harm experts urge caution. The authors note:
"Attention deficit hyperactivity disorder (ADHD) is one of the most commonly diagnosed and treated psychiatric disorders in childhood. Typically, children with ADHD find it difficult to pay attention, they are hyperactive and impulsive...Methylphenidate is the drug most often prescribed to treat children and adolescents with ADHD but, despite its widespread use, this is the first comprehensive systematic review of its benefits and harms."
They set out to assess the beneficial and harmful effects of methylphenidate for children and adolescents by reviewing all randomised controlled trials (RCTs) comparing methylphenidate versus placebo (or no intervention) in children and adolescents aged 18 years and younger. They mined comprehensive data from six databases (CENTRAL, Ovid MEDLINE, EMBASE, CINAHL, PsycINFO, Conference Proceedings Citations Index), and two trials registers and contacted the pharmaceutical companies that manufacture methylphenidate for their published and unpublished data.
"We found 185 randomised controlled trials (RCTs; studies in which participants are randomly assigned to one of two or more treatment groups), involving 12,245 children or adolescents with a diagnosis of ADHD. Most of the trials compared methylphenidate to a placebo – something designed to look and taste the same as methylphenidate but with no active ingredient. Most trials were small and of low quality. Treatment generally lasted an average of 75 days (range 1 to 425 days), making it impossible to assess the long-term effects of methylphenidate. Seventy-two of the 185 included trials (40%) were funded by industry."
Some ADHD symptoms might improve but the evidence is poor
Methylphenidate can have side effects including sleep problems and loss of appetite, and there is no scientific data on its long term effects—a grave consideration for a brain-modifying drug.
"The quality of the evidence was very low for all outcomes. It was possible for people in the trials to know which treatment the children were taking, the reporting of the results was not complete in many trials and for some outcomes the results varied across trials. These considerations limit our confidence in the overall results of the review.
The lead authors lOle Jakob Storebø, PhD, clinical psychologist, Region Zealand, Roskilde, Denmark, and Morris Zwi, MBBCh, consultant child and adolescent psychiatrist, Whittington Health, London, UK, are quoted in Medscape Medical News:
"The evidence is not as convincing as many clinicians have believed regarding the benefits of methylphenidate...In general, our findings raise concerns about how much we should expect of this medicine, and there needs to be more caution when prescribing methylphenidate."
Furthermore...
"Clinicians need to weigh what we now believe to be an uncertain degree of benefit against the many adverse events that are known to be associated with methylphenidate, such as appetite suppression and sleep difficulties. The general perception of methylphenidate as an effective drug for all children with ADHD seems out of step with the new evidence. This new information from our review should challenge the mindset of clinicians because there is more uncertainty to factor in to balancing the benefits and risks of this medication."
Clinical Note
Practitioners participating in case management of ADHD should overcome any bias and consider the authors' conclusions:
"At the moment, the quality of the available evidence means that we cannot say for sure whether taking methylphenidate will improve the lives of children and adolescents with ADHD. Methylphenidiate is associated with a number of non-serious adverse events such as problems with sleeping and decreased appetite. Although we did not find evidence that there is an increased risk of serious adverse events, we need trials with longer follow-up to better assess the risk of serious adverse events in people who take methylphenidate over a long period of time."
Improving brain health by treatment plans that target dysfunction and deficiencies with appropriate objective tests is preferable to medicating a stimulant that has side effects, uncertain benefit and unknown long term effects. For a list of fundamental methods of assessing brain physiology that can form the basis of a rational treatment plan download the free Parents' Guide To Brain Health from Useful Links on the right.