FRIDAY, Sept. 17 (HealthDay News) -- More and more children with attention-deficit/hyperactivity disorder (ADHD) who act out aggressively are being given antipsychotic drugs in addition to stimulant medications to help control their volatile outbursts.

It's a trend that many parents and child mental health professionals find worrisome.

However, a new study by researchers at New York's Stony Brook University School of Medicine suggests that, with careful tweaking, use of stimulant medication alone can significantly reduce or eliminate aggressive behavior in at least half of these children.

"There's a big push in this country to have pediatricians manage these kinds of behavioral difficulties in children because there's such a shortage of child psychiatrists," noted the study's lead author, Joseph C. Blader, an assistant professor of psychiatry at Stony Brook. "I hope our study will embolden more primary care physicians to push the limits of first-line [stimulant] treatment for ADHD before going on to the next thing."

The study findings were released online Sept. 13 in advance of publication in the October print issue of Pediatrics.

Blader said the results were an unexpected finding that occurred during the lead-in phase of a study designed to look at whether it was beneficial to give the antipsychotic medication divalproex (Depakote) to aggressive kids with ADHD whose volatile behavior wasn't controlled by stimulant medication alone.

The researchers followed 65 children between the ages of 6 and 13 to determine the most effective and best-tolerated stimulant regimen for each of them. All of the kids had ADHD plus either oppositional defiant disorder or conduct disorder, with significant aggressive behavior. The children were started on a low dose of triphasic-release methylphenidate (Concerta), the longest acting form of Ritalin.

During weekly assessments, the researchers fine-tuned the dose until the child's symptoms were well-controlled and he or she could tolerate any side effects (mainly insomnia and loss of appetite). If Concerta wasn't the right choice, a child was switched to either biphasic methylphenidate (Metadate) or biphasic mixed amphetamine salt medication (Adderall XR).

Children and their parents also had weekly behavioral therapy sessions, during which parents were encouraged to "emphasize the times when their children were able to show self-control and manage their frustrations better," Blader said. "The goal was to help parents develop rewards and incentives, while at the same time, set limits around some of the problem behaviors."

At the end of the lead-in phase, which lasted an average of five weeks, 32 of the children showed significant reductions in their aggressive behavior.

"I was very surprised by how many of the kids we couldn't randomize [to an antipsychotic medication] because their aggression went away" as doctors adjusted their type or level of stimulant drug, said Blader.

"This is an important message about hanging in there with a medication," noted Dr. Chris Varley, a child psychiatrist at Seattle Children's Hospital. He said in the last decade, there's been a dramatic increase in the use of antipsychotic medications to reduce disruptive behavior in children, and in many cases the drugs are not necessary.

"Sometimes you do need to use these medications, but in this day and age, the trigger may be pulled too quickly," said Varney, who is professor of child and adolescent psychiatry at the University of Washington School of Medicine.

Blader said the advice for children and their parents is to not get discouraged if the first ADHD drug and dosage doesn't work.

"Just like with asthma or many other health problems, it's often a bit of an exercise to find what does the trick," he said.

The researchers received funding from the U.S. National Institutes of Health and the National Alliance for Research on Schizophrenia and Depression.

More information

Find out more about ADHD at the U.S. National Institute of Mental Health.