THURSDAY, Feb. 10, 2005 (HealthDay News) -- The Canadian pullback of the drug Adderall XR will not prompt similar measures south of the border.
The U.S. Food and Drug Administration (FDA) said Thursday it was satisfied with the safety profile of the medication, which is used to treat attention-deficit hyperactivity disorder (ADHD).
"Given the data we have in front of us now, we're fairly confident with the decision we've made," said Dr. Russell Katz, director of the division of neuropharmacological drug products at the FDA. "As far as we can tell, the evidence does not indict the drug."
There are 2 million children in the United States who have been diagnosed with ADHD, according to the National Institute of Mental Health. Adderall XR is taken by about 700,000 people in this country, according to the Associated Press, while another 300,000 take the immediate-release form of the medication called Adderall.
Canada's move to suspend sales of the drug was prompted by 20 sudden deaths, 14 of them in children, in those taking the recommended doses of Adderall XR. A dozen strokes, two in children, were also reported. All of the deaths, which go back to 1999, occurred in the United States.
The FDA's decision, according to an official statement, was not to make "any immediate changes" in "FDA labeling or approved use of this drug." In an agency alert published online Wednesday, the FDA noted the Canadian move and the data that prompted it, adding, however, that "at this time, FDA cannot conclude that recommended doses of Adderall can cause sudden unexplained death, but is continuing to carefully evaluate these data."
In August, the agency changed the label of the drug to indicate it might cause problems in people with underlying structural heart defects.
Doctors in the field described the drug as effective, yet potent.
"The drug is very effective and fairly widely prescribed," said Dr. Lenard Adler, director of the Adult ADHD Program at New York University Medical Center.
At the same time, added Dr. Jon A. Shaw, director of child and adolescent psychiatry at the University of Miami School of Medicine, "it is a powerful drug and needs to be used judiciously and with careful forethought, being attentive to possible adverse effects and interaction with other drugs." The drug has been associated with an increased heart rate, increased blood pressure and irregular heartbeats, he added.
The main concern about Adderall to date had been its addictive properties, not sudden cardiac death.
"There's pretty good evidence that these are drugs that are easy to get addicted to," said Dr. James M. Perrin, a professor of pediatrics at Massachusetts General Hospital for Children in Boston and chairman of the American Academy of Pediatrics committee that wrote the diagnostic and treatment guidelines for ADHD. "There's much less good evidence that children can get addicted."
According to Katz, five of the children who died had underlying structural heart defects. Many of the other cases had mitigating circumstances, he added.
"When you look at those cases, there are a number of seriously confounding events, things that might make you think it was something else," he said. One child was in boot camp, and had been exercising in extremely hot temperatures. There were also other cases of extreme exercise, as well as cases of high amphetamine levels in the blood, Katz stated.
The FDA is also not convinced that these deaths are necessarily greater than in the population at large or in other drug categories.
Will they continue to investigate? "We think we've got all the relevant data for 1999 forward, at least with regard to sudden death," Katz said. "There really isn't a lot more for us to do in terms of data analysis."
There is still some ongoing work with background rates, and Katz said they may look at death rates further back. It was an open question whether additional studies needed to be done, he said.
Shire Pharmaceuticals, the British company that makes Adderall, strongly defended its product Thursday.
"Although we are complying with this request, we strongly disagree with this decision," Shire spokeswoman Jessica Mann told Bloomberg News. "We have confidence in the safety and efficacy of Adderall XR."
Most doctors indicated that they would not change their practices.
"It's important to remember that are substantial risks of not treating ADHD," Adler said. "Individuals are more likely to smoke cigarettes, use substances, get divorced or separated, have motor vehicle accidents, underperform on the job and get fired."
"Parents and professionals need to bear in mind that although it's certainly concerning that there seems to be an association with 20 or so deaths, 99.99 percent of children and adolescents have not had any problems," added Dr. Andrew Adesman, chief of developmental and behavioral pediatrics at Schneider Children's Hospital in New York City.
And there are other medications that can be used to treat ADHD, most notably methylphenidates such as Ritalin, that have not shown the same risks.
"We need to get more information, but this could change the landscape of treatment," Perrin said. "There are other treatments that could be used. I suspect doctors who use this a lot will at least be thinking about alternatives."
Children and Adults with Attention-Deficit/Hyperactivity Disorder (CHADD), the nation's leading support and advocacy group, posted a statement about Canada's move on its Web site Thursday.
"CHADD recognizes that families seek a variety of effective treatments given the uniqueness of a child's clinical needs, coupled with the philosophy of the family. The choice to use or not use medication -- along with the choice of what medication -- is an individual decision made between the treating professionals and the family," the statement said. "CHADD will continue to monitor the situation closely for any developments from the FDA and provide timely responses as necessary."
The U.S. Food and Drug Administration has a public health alert on Adderall.