Psychostimulant medications, including methylphenidate (Ritalin, Metadate, and Concerta), amphetamine (Dexedrine, Dextrostat, and Adderall), and a newer drug, atomoxetine (Strattera, marketed as a "non-stimulant," although its mechanism of action and potential side effects are essentially equivalent to the "psychostimulant" medications), are by far the most widely researched and commonly prescribed treatments for ADHD. Numerous short-term studies have established the safety and effectiveness of stimulants and psychosocial (behavioral therapy) treatments for not only alleviating the symptoms of ADHD but also improving the child's ability to follow rules and improve relationships with peers and parents. National Institute of Mental Health (NIMH) research has indicated that the two most effective treatment modalities for elementary-school children with ADHD are a closely monitored medication treatment or a program that combines medication with intensive behavioral interventions (behavior therapy). In the NIMH Multimodal Treatment Study for Children with ADHD (MTA), which included nearly 600 elementary-school children across multiple sites, nine out of 10 children improved substantially on one of these treatment programs.
Two types of antidepressant medications, the "tricyclic antidepressants" (TCA) (imipramine, desipramine, and nortriptyline) and bupropion (Wellbutrin) have also been shown to have a positive effect on all three of the major components of ADHD: inattention, impulsivity, and hyperactivity. They tend, though, to be considered as second options for the children who have shown inadequate response to stimulant medication or who experience unacceptable side effects from stimulant medication such as tics (uncontrolled movement disorders) or insomnia. The antidepressants, however, have a greater potential for side effects of their own, such as heart-rate and rhythm changes, dry mouth, headaches, and drowsiness, to name a few. If higher doses are required, bupropion may bring on seizures. The antidepressants, therefore, require more careful monitoring.
For the child who has a combination of ADHD and comorbid conditions such as depression, anxiety disorders, or mood disorders, stimulant medications can be combined with an antidepressant medication very successfully.
Are there standard doses for these medications?
For most children, stimulant medications are very safe and extremely effective. Research has shown that up to 80% of ADHD children show very good to excellent response to these medications. Improvements in the delivery systems for these medications in the last few years that have allowed the child to frequently only require one dose per day, alleviating the embarrassing "trip to the nurse's office" for a midday dose at school. Recently, a skin patch (Daytrana, a methylphenidate transdermal system) that, when applied daily, delivers the medication at a carefully controlled rate. The doctor will work with the child and his family to find the best medication, dosage, schedule, and delivery system. This requires careful individualization, since some children respond to one type of stimulant much better than another and each child's daily needs and schedules are so variable.
How long are children on these medications?
The expected duration of treatment has lengthened during this past decade as evidence has accumulated that benefits extend into adolescence and adulthood. Medication usage during the teen years can become problematic. The natural rebellion and desire for independence can make the adolescent protest against taking a medication. The need for a medication may reinforce anxiety that is common during the teen years in that it reinforces the notion of "I am different" to an age range that craves "fitting in." As such, parents and physicians must empower the teen to become a partner rather than a mere participant in his/her health. In some circumstances, it may even be necessary to allow the teenager to suffer the effects (academic and social) should he refuse to take medication. It is frequently the case that medication will be required into adulthood, and these years are critically important ones for the adolescent to begin to learn self-management of medication and other issues related to ADHD.
Hasn't the use of stimulant medication become excessive?
While it is certainly true that the prescribing of stimulant medication has increased sharply in the last 15 years, the statistics indicate that this increase coincides with the number of legitimately diagnosed cases of ADHD worldwide. Physicians, and the population in general, have achieved a much greater degree of awareness of and acceptance of the biological nature of ADHD, as well as the dramatic effectiveness of treatment protocols.
Are there differences in stimulant use across racial and ethnic groups?
There are significant differences in access to mental-health services between children of different racial groups; and consequently, there are differences in medication use. In particular, African-American children are much less likely than Caucasian children to receive psychotropic medications, including stimulants, for treatment of mental disorders.
Why are stimulants used when the problem is overactivity?
Recall that the three key components in ADHD are inattention, impulsiveness, and hyperactivity. While the exact nature of the disorder at the brain-cell level is not completely understood, it is felt that the medications work by stimulating the brain cells to make more of the chemicals (neurotransmitters) available that send messages from one brain cell to another. This improved message-sending system enhances the brains ability to pay attention, control behavior and impulses, plan actions, and follow through on schedules.
What are the risks of the use of stimulant medication and other treatments?
Stimulant medications have been successfully used to treat patients with ADHD for more than 50 years. This class of medication, when used under proper medical supervision, has an excellent safety record in patients with ADHD. In general, the side effects of the stimulant class of medications are mild, often temporary, and reversible with adjustment in dosage amount or interval of administration. The incidence of side effects is highest when administered to preschool-aged children. Common side effects include appetite suppression, sleep disturbances, and weight loss. Less common side effects include an increase in heart rate/blood pressure, headache, and emotional changes (social withdrawal, nervousness, and moodiness). Patients treated with the methylphenidate patch (Daytrana) may develop a skin sensitization at the site of application. Approximately 15%-30% of children treated with stimulant medication develop minor motor tics (involuntary rapid twitching of facial and/or neck and shoulder muscles). These are almost always short-lived and resolve without stopping the use of medication.
A recent investigation studied the possibility of stimulant medication used to treat ADHD and cardiovascular side effects. Concern focused on a possible association with heart attack, heart-rate and rhythm disturbances and stroke. At the time of the writing of this article, there is no certainty as to the relationship to these event (including sudden death) when medication is used in a pediatric population screened for prior cardiovascular symptoms or structural pathology. A positive family history for certain conditions (such as unusual heart-rhythm patterns) may be considered a risk factor. The current position of the American Academy of Pediatrics is that a screening EKG is not indicated before initiation of stimulant medication in a patient without risk factors.
Will children taking these medications for ADHD become drug addicts?
Although an increased risk of drug abuse and cigarette smoking is associated with childhood ADHD, this risk appears due to the ADHD condition itself, rather than its treatment. In a study jointly funded by the NIMH and the National Institute on Drug Abuse, boys with ADHD who were treated with stimulants were significantly less likely to abuse drugs and alcohol when they got older. Caution is warranted, nonetheless, as the overall evidence suggests that people with ADHD (particularly untreated ADHD) are indeed at greater risk for later alcohol or substance abuse. Because some studies have come to conflicting conclusions, more research is needed to understand these phenomena. Regardless, in view of the substantial, well-established findings of the harmful effects of inadequate treatment or no treatment for a child with ADHD, parents should not be dissuaded from seeking effective treatments because of misconstrued or exaggerated claims about substance-abuse risks.
"Diversion" is the transfer of medication from the patient for whom it was prescribed to another individual. Several large studies have indicated that 5%-9% of grade and high-school students and 5%-35% of college-age individuals reported use of non-prescribed stimulant medication. Approximately 16%-29% of students for whom stimulant medications were prescribed reported being approached to give, trade, or sell their medication. Misuse was more frequently seen in whites, members of fraternities and sororities, and students with a lower GPA. Diversion was more likely with the short-acting preparations. The most common reasons cited for use on non-prescribed stimulants were they "helped with studying," improved alertness, drug experimentation, and "getting high."
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