U.S. advisers on Wednesday called for new information about psychiatric and heart risks on the labels of attention deficit drugs but stopped short of recommending the strongest possible warning, saying they did not want to frighten patients or parents from effective treatment.

The panel of pediatric experts reviewed reports of heart problems, psychotic behavior, hallucinations and other psychiatric symptoms, in children who took the medicines, which include Novartis AG’s Ritalin and Shire Plc’s Adderall.

Patients, parents and doctors should know about the reports even though it is unclear if the drugs contributed to the problems, panel members said. They declined to recommend the “black box” warning - the strongest for prescription drugs - that a different advisory panel narrowly endorsed last month.

“You have overwhelming evidence of efficacy with two rare adverse events ... A black box would scare many patients away from treatment,” said panel chairman Dr. Robert Nelson, a critical care specialist at The Children’s Hospital of Philadelphia.

The Food and Drug Administration will consider both panels’ recommendations before making a final labeling decision. Dr. Robert Temple, director of the FDA’s medical policy office, said officials likely would follow the pediatric panel’s recommendations for explaining risks to children but were still mulling what to say about the dangers for adults.

Millions take prescription drugs to treat attention deficit hyperactivity disorder (ADHD). The condition causes trouble with focus as well as hyperactivity and impulsiveness. Symptoms can be so disabling that they interfere with school or work and personal relationships.

Other ADHD drugs include Johnson & Johnson’s Concerta, Novartis’s Focalin, GlaxoSmithKline Plc’s Dexedrine and Eli Lilly and Co.‘s Strattera.

Critics say the drugs are prescribed to people who do not need them.

The recent safety concerns have added to the controversy. FDA reviewers have been working for months to analyze reports of sudden deaths, heart attacks and strokes as well as psychiatric symptoms.

FDA staff said they were struck by reports of several children under age 10 who were taking the drugs and mistakenly thought they saw or felt bugs, snakes and worms crawling on them. The hallucinations and other episodes most often occurred in patients with no known risks factors for such behavior, FDA staff said.

Panel members said they thought those problems should be highlighted on the ADHD drug labels and described in a patient-friendly guide handed out with prescriptions.

Cardiac problems also should be noted, panel members said, but stressed they are most likely to be seen in children with a history of heart problems or in adults.

“In the general run-of-the-mill kid, I think (ADHD drugs) are well-tolerated. I don’t think there’s much risk at all if they don’t have a heart condition,” said Dr. John Moore, a panel member and pediatric cardiologist at Mattel Children’s Hospital at UCLA in Los Angeles.

Last month, a different FDA panel of drug safety experts voted 8-7 to recommend a black box warning about the potential for cardiac complications.

Adderall already carries a black box warning that misuse could lead to cardiovascular problems, and Strattera has one cautioning that children and teens who take it could have suicidal thoughts.

Makers of the ADHD drugs said they would work with the FDA to make sure risks were communicated adequately.

“We are supportive of the suggestion that they made…of having some type of heightened awareness around potential adverse events,” Shire spokesman Matthew Cabrey said.