Placebo May Augment Effects of ADHD Meds
Small Study Suggests Low-Dose Medications Helpful When Paired With Placebo
While Bodfish's study was small and lasted only three months -- too short to study long-term effects -- he is currently testing this theory in a larger trial involving 150 ADHD children for longer period, courtesy of a National Institutes of Health grant.
The pill initially used with a half-dose of regular active medication was made to look visually distinctive, and the patients and their parents were fully told of the study's intention. "We explained that previous studies have shown that you can condition medication effects with a placebo, and there is a possibly they could get similar effects with less side effects using this placebo pill with a lower dose of their regular drug," Bodfish says.
This conditioning response may be behind the so-called "placebo effect," the reason why many participants in medical studies respond favorably when given the "dummy" pills, which primarily consist of sugar.
However, the study was too small and short-term to draw convincing conclusions, say two experts not involved in the research.
"This is certainly an interesting finding, and they present a great theory that is consistent with other studies," says neurologist Thomas Megerian, MD, PhD, ADHD specialist at Children's Hospital of Boston. "We see around a 30% response rate to placebo in depression and many other psychiatric conditions. But at this point, these researchers are hinting at an effect but the results aren't there."
Megerian says that while the study results suggest improvement with placebo, the results were not statistically significant. "This is what we call 'a trend toward significance,' but we're not there yet," he tells WebMD. "This is probably why the NIH said, 'do this on a larger number of people.'"
In other words, while more children responded well with the placebo, some children -- though not as many -- also responded well to a lower dose of medication without the sugar pill. "It's hard to tell in this study what these kids needed in terms of medication," Megerian says. "Maybe all the kids needed to be on half the dose of medication, since no information was given on how severely affected they were. Were these borderline cases of ADHD, children who didn't need much of a nudge to get them across to responding favorably? It's good that they're doing more research, because more is needed."
Another ADHD specialist tells WebMD says that because the children studied received alternating doses for week-long periods, it's hard to determine the real effect of the placebo. Most ADHD children have their medication dosages altered repeatedly over the course of their treatment, says David Rabiner, PhD, of Duke University and a spokesman for CHADD, an ADHD patient advocacy group.
"And previous studies suggest that kids who receive behavior treatment in conjunction with their medication, on average, are maintained on lower doses of medication," he tells WebMD. "So what is important for parents to know is that if a child needs to be on [ADHD] medication, and they would like their child to be managed on lower doses, there is evidence that if the child gets good behavioral intervention, they may be able to reduce the need for higher dosages. It would be unfortunate if it was interpreted from this study, and I know it's not the authors' intention, that the medication doesn't do anything and they could just cut their child's dosage in half."