TCR: Dr. Diller, you’re a rare bird in the ADHD world in that you are skeptical of our reliance on stimulants for treating this condition, and yet you have an unusually good grasp and appreciation of how and when to use them. What is your background?
Dr. Diller: I’ve practiced developmental/behavioral pediatrics for 27 years in the suburban East Bay Community of Walnut Creek, and I am on the clinical faculty at UCSF. I have scrupulously avoided taking money from any drug companies, in part because I continue to prescribe psychiatric medications for children, and I feel that if I did accept drug money, my credibility would be seriously compromised.
TCR: Let’s talk a bit about Adderall XR, since it has recently been approved for the treatment of adult ADHD and has been on the news lately because of safety concerns.
Dr. Diller: The story of Adderall is interesting, because when it was first introduced (as the immediate release version) it was heavily promoted as a major leap over Ritalin, because it lasted longer. But that was an unfair comparison because it really should have been compared with Dexedrine Spansules, a longer half-life medication that had already been around for years. Eventually, about three years ago, Adderall IR was compared with Dexedrine Spansules in an NIMH-funded study and the Spansule was shown to exhibit a more consistent six to eight hour length of action and was a more effective medication four hours after kids took it (ed. note: J Am Acad Child Adolesc Psychiatry 2001; 11:1268-76). Indeed, when I started using Adderall IR, I found that people would say it wore off after four or five hours. The length of action in Adderall is very variable, in my experience.
TCR: So the immediate release version of Adderall didn’t offer any advantage over Dexedrine Spansules?
Dr. Diller: No, but they priced Adderall IR about three cents cheaper than Dexedrine Spansules and they marketed it heavily to doctors, so that within two years of its introduction, Adderall IR had surpassed Ritalin as the most frequently prescribed brand-name drug.
TCR: How does all this relate to Adderall XR, the extended release version?
Dr. Diller: After Concerta was approved in 2000, Adderall IR’s position was highly threatened because here was a truly innovative delivery system–osmotic release with an intact capsule–and it seemed to genuinely deliver 10 to 12 hours of methylphenidate release. Compared to Adderall IR, it was a much better product, in my opinion. And so within months, we started hearing about Adderall XR.
TCR: Does Adderall XR have any advantages over Concerta?
Dr. Diller: No. It can last as long as Concerta, but in general I choose a methylphenidate product like Concerta first because, despite large group studies indicating that amphetamine and methylphenidate are equally effective and have about the same side effects, 27 years of experience tell me that amphetamines are a little bit more likely to produce insomnia, even with just a morning dose of Adderall, and even when you use the IR formulation. If methylphenidate is not successful in a given patient, however, I will try an amphetamine product before I move to something else. Why? Because there is good evidence that failure to respond to one form of stimulant doesn’t mean that patients won’t respond to the other one positively. Overall, I would say I have an 80-90 percent success rate using one or another form of stimulant medication.
TCR: Can you comment on the recent Canadian government decision to temporarily halt the sale of Adderall XR in Canada?
Dr Diller: Apparently there have been 20 reported sudden deaths in children and adults (on stimulants) between 1999 and 2004. Thirteen took Adderall XR but the concern should exist for all stimulants. Sixteen of the 20 had preexisting cardiac structural or arrhythmia problems. I do believe these deaths were probably stimulant-related (unlike some who suggest this percentage mimics the “natural” sudden death rate in children). That said, there’s probably a higher chance of being hit by a drunk driver and dying on the freeway than dying from taking Adderall. You’ll still take the freeway because it gets you where you want to go faster. It hasn’t changed my prescribing choices, even with one of my patients who is a nine year-old survivor of a hypoplastic left heart syndrome repair. His ADHD symptoms were severe and quite responsive to Metadate ER (methylphenidate extended release), so in concert with his pediatric cardiologist and parents I continue to prescribe the drug for him despite the Canadian decision.
TCR: Are there particular clinical scenarios that lead you to choose one stimulant treatment over another?
Dr. Diller: I try to be sensitive to the specific problems of the disorder rather than saying, “You have ADHD, go on Concerta.” In fact, I just got a call from a parent yesterday with a five-year-old in kindergarten whose family doctor put the child on Concerta. My question to the parent was, “Why?” Because in fact at home the child wasn’t much of a problem. In very young children up to about second grade, the bulk of the work that the kid has to do is in the morning, and in this case Concerta is often overkill; a three to four hour drug taken in the morning makes more sense. This allows the kid to have an appetite for lunch and to have an otherwise good rest of the day. So instead of being yelled at by the teacher in the morning he has been successful, and this gets his own endogenous endorphins working to help him throughout the day, even after the stimulant has worn off.
TCR: What about stimulants for older school age kids?
Dr. Diller: After first or second grade, kids will be getting more schoolwork in the afternoon. From about second grade to fifth grade or so, Metadate ER is an overlooked choice. More people have heard about Metadate CD (oncea-day dosing), but Metadate ER gives a very nice six to eight hour coverage. Dexedrine Spansule also is a good choice for school day coverage.
TCR: These are both shorter acting than Concerta and Adderall XR?
Dr. Diller: Yes, and parents love these moderate-lasting drugs. Parents are reluctant to put their kids on medications, and the less time that the medication is active, the better from their point of view. Now in some cases the choice of medication will come down to how difficult homework completion is at home. If homework completion is an issue even for the middle school aged child, then some parents will choose Concerta. But otherwise they say, “Oh no, we can manage homework with a structured reward and punishment system here. We want just a school day coverage.” I think this issue is often overlooked in recommendations and I think clinicians should really consider Metadate ER or Dexedrine Spansule as opposed to Concerta in this age group.
TCR: What about Ritalin SR (sustained release)?
Dr. Diller: Ritalin SR is from the Paleolithic era and many people saw it as an early attempt to extend the patent on Ritalin. It never impressed me as more effective than Ritalin.
TCR: And what are your thoughts about Focalin?
Dr. Diller: Focalin is the dextro-isomer of methylphenidate, which is considered the active isomer. What that allows you to do is to prescribe half the dose for the same effect, and in my opinion this only has psychological benefits for the parents. They can feel better about giving their kids only 2.5 mg of Focalin, instead of 5 mg of Ritalin, but otherwise there is no difference aside from the much higher cost of Focalin. The idea that Focalin has fewer side effects is not true. So Focalin is simply another player on the grand tour of “me too” medications that you can embark on with the patient if that is the only thing that you do. The likelihood of being more successful with a third medication after you have tried two of them goes down markedly. Or if it is successful, I couldn’t attribute it to the drug.
TCR: While you often use stimulants in your practice, you have been critical of what you feel is an over-reliance on these drugs. Can you expand a bit on your views about this?
Dr. Diller: I believe our culture is obsessed with performance, and our increasing use of stimulants reflects that obsession. In my own practice, I see two types of kids with ADHD: those with severe ADHD, who definitely need stimulants, and those with what I call garden variety “Tom Sawyer” ADHD, who I believe constitute the vast majority of children taking stimulants today.
TCR: Define Tom Sawyer ADHD.
Dr. Diller: Tom Sawyer ADHD is for the kids who are definitely struggling in school, have some problems with impulse control, have interests and talents that are not necessarily what the adults want, but when these kids are interested in something, they focus fine. That kind of behavior has been redefined as pathology, and there is no question in my mind that Tom Sawyer and Huck Finn would be taking medication today. I believe that the vast bulk of children we see are simply extremes of normal variations of temperament or talent diversity, and we should be more cautious about jumping to medication in these cases. We tend to use the categorical nature of ADHD to justify treatment, although we know that ADHD and ADD are actually a spectrum of disorders and that there is a large group of kids who are sitting in the penumbra of the diagnosis who could be very amenable to behavioral and educational intervention.