Despite recommended limits on codeine use in children, the potent painkiller is prescribed in pediatric cases in at least half a million emergency-room visits each year, a study suggests.

Use of the drug in that setting is hardly rampant — just 3 percent of children’s ER visits resulted in codeine prescriptions in 2010, the 10-year study found. But with more than 25 million ER visits by children each year, the authors say far too many are getting the drug when better options are available.

Codeine is an opiate, and a genetic variation makes some people metabolize it too quickly, potentially resulting in dangerous side effects, including excessive sleepiness and difficulty breathing. The Food and Drug Administration issued its strictest warning last year about a rare risk for life-threatening complications or death in children given the drug after certain surgeries. It advises using codeine for children’s pain only if the anticipated benefits outweigh the risks. Codeine was once commonly used for coughs, but the American Academy of Pediatrics recommends against that use because of the risks and a lack of evidence that the drug does relieve coughs.

Injuries and respiratory symptoms are the top reasons for children’s ER visits. The study’s authors analyzed national data from 2001 to 2010 on ER visits for patients ages 3 to 17. The portion of visits where codeine was prescribed dipped slightly during the study. But the authors estimated the yearly number of visits in which codeine was used ranged from almost 560,000 to 877,000. Information on any side effects was not included in the data.

The study was published online Monday in Pediatrics.

Kathleen Neville, a pediatric drug expert at Children’s Mercy Hospitals and Clinics in Kansas City, Mo., said it is likely the numbers have declined since the study ended, given the FDA’s warning.

A spokesman for the American College of Emergency Physicians, Alfred Sacchetti, said codeine can be safely used in many children, especially if they are older. Children typically are monitored in the ER after getting codeine and would not be sent home with a prescription if they had a bad reaction or it did not work, he said.

Children on codeine who develop breathing problems or unusual sleepiness should get immediate medical attention, the FDA says. The study’s lead author, Sunitha Kaiser, an associate pediatrics professor at the University of California at San Francisco, said that doctors and parents should know about codeine’s drawbacks and that alternatives are available, including dark honey for coughs in children over age 1 and ibuprofen or the opiate drug hydrocodone for pain including broken bones.

Associated Press