Children suffering from attention deficit hyperactivity disorder (ADHD) should get a cardiac evaluation before receiving treatment with stimulant drugs, the American Heart Association recommended Monday.

According to government estimates, about 2.5 million American children and 1.5 million adults take medication for ADHD. To help these children stay focused and control their behavior, doctors prescribe drugs like Ritalin (Novartis AG), Adderall (Shire Pharmaceuticals Group PLC), Concerta (Johnson & Johnson) and Strattera (Eli Lilly & Co.) considered stimulants.

These drugs can increase blood pressure and heart rate, which, for most children, is not a problem. However, for children with heart conditions, stimulant drugs could make them more vulnerable to sudden cardiac arrest – an erratic heartbeat that causes the heart to stop pumping blood through the body – and other heart problems.

“There's been concern that these drugs might be associated in a very small number of individuals' sudden cardiac arrest or sudden cardiac death. There's no registry in the country to determine how many young people are dying from sudden cardiac arrest and what they might have causing that -- and similarly how many of those who die might be on these medications. So there's no causal information,” said Dr. Victoria Vetter of the University of Pennsylvania School of Medicine in Philadelphia, who led the panel that drafted the recommendations, Reuters reports.

The AHA recommendations come a year after the Food and Drug Administration got reports that 19 children had died suddenly and an additional 26 suffered strokes, cardiac arrests, or other cardiovascular events while on the medication between 1999 and 2004. Following this report, a warning about possible risk to people with heart problems was added to the labels of these drugs.

According to the new recommendations, all children should receive careful heart screenings that include electrocardiograms (EKGs) to rule out heat abnormalities before being started on stimulants for ADHD. Moreover, children who are already on the ADHD treatment but did not receive an EKG should get one. During ADHD treatment, people should have blood pressure check-ups once every one to three months as well as routine health check-ups every six to twelve months.

“We don't want to keep children who have this from being treated. We want to do it as safely as possible,” said Dr. Vetter.

Representatives for Shire PLC and Novartis said the labeling already suggests patients be evaluated for heart problems and an EKG done if needed.

"There's no new information here. And frankly, we're a little perplexed as to the purpose of the American Heart Association coming out with this statement at this time," said Shire spokesman Matt Cabrey as quoted by the Associated Press.

An ADHD advocacy group called CHADD welcomed the AHA recommendations saying parents should monitor their children’s reaction to all medications. EKG screening "will bring an even further measure of safety to what is already a safe clinical treatment approach," the group said.

Also other health specialists praised the AHA recommendations. “While no screening method will be perfect, if you do a good physical exam, a history and an electrocardiogram, you're going to identify most of the disease that will be adversely affected by getting a stimulant. This is reasonable and prudent,” said Steven Nissen, head of cardiology at the Cleveland Clinic, who urged warning labels for the stimulant drugs.