A study that found possible heart risks with attention deficit drugs had limitations and should not prompt parents to stop giving the medications to children, the U.S. Food and Drug Administration said on Monday.

The FDA said the study published on Monday in the American Journal of Psychiatry found there may be an association between use of stimulant medications used to treat attention deficit hyperactivity disorder (ADHD) and sudden cardiac death in healthy children.

"Because of the study's limitations, parents should not stop a child's stimulant medication based on the study," an FDA statement said.

Stimulant medications used to treat ADHD include Novartis AG's Ritalin and Shire PLC's Adderall and Vyvanse.