An estimated 7 percent of children ages three to 17 in the U.S. have ADHD. As of 2007, an estimated 2.7 million children in that age group were taking medication to help control their symptoms.

But for many, ADHD medications are of little use.

A six-year study by researchers at Johns Hopkins University concluded that, despite treatment, nine out of 10 children with moderate to severe ADHD still exhibit severe symptoms and learning impairment. 

Researchers say their findings shed “much-needed light” on how the condition naturally progresses, especially since children are being diagnosed at an increasingly younger age. 

“ADHD is becoming a more common diagnosis in early childhood, so understanding how the disorder progresses in this age group is critical,” Mark Riddle, M.D., a pediatric psychiatrist at Johns Hopkins Children's Center and lead study author, said in a press release. “We found that ADHD in preschoolers is a chronic and rather persistent condition, one that requires better long-term behavioral and pharmacological treatments than we currently have.”

Treatment Outcomes by the Numbers

Researchers enlisted children ages three to five who had already been diagnosed with ADHD. The children were treated for a few months and given ongoing care by pediatricians. Their progress was documented over the course of six years, along with information about their school performance, behavior, and overall health.

One surprising finding was that while two-thirds of the children studied were taking ADHD medication, there was little difference in symptom severity between them and the children not taking stimulant drugs. 

“Specifically, 62 percent of children taking anti-ADHD drugs had clinically significant hyperactivity and impulsivity, compared with 58 percent of those not taking medicines,” the study says. 

Inattention was also an issue. Nearly two-thirds of both medicated and non-medicated children reported inattention as a significant and debilitating symptom.

What the Study Doesn’t Say

While the data suggest that medication isn’t effective for more than half of the children taking it, researchers caution against jumping to conclusions about why drug therapies don’t work.

They said it could be related to poor medication choice, improper dosing, or simply that the children weren’t taking their medications.

“Our study was not designed to answer these questions, but whatever the reason may be, it is worrisome that children with ADHD, even when treated with medication, continue to experience symptoms, and what we need to find out is why that is and how we can do better,” Riddle said.

Riddle's findings were published this week in the Journal of the American Academy of Child & Adolescent Psychiatry.

What’s a Parent to Do?

The last thing a parent should do is to immediately stop giving his or her child prescribed ADHD medication. Some medications can cause severe withdrawal systems. 

Talk to your child’s pediatrician if your child continues to display severe symptoms that affect his or her behavior or performance in school. 

This study highlights the fact that no one treatment works for every child, but with all the alternative and supplemental therapies that can work alongside or in place of medications, there is always reason to hope.

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