Codeine has been used to treat kids' pain and coughs for decades "because we thought it was safer than other narcotics," said report author Dr. Joseph Tobias.
But doctors have learned that the way codeine is processed in the body is very dangerous for children and can result in death, said Tobias, chief of anesthesiology and pain medicine for Nationwide Children's Hospital in Columbus, Ohio.
Codeine is converted by the liver into morphine, but genetic differences between people can prompt the liver to create too much morphine in some and too little in others, he explained.
"Now, lo and behold, we're learning that due to this genetic variation it's a very dangerous medication," Tobias added.
Children who rapidly metabolize codeine into an overdose of morphine can experience severely slowed breathing rates, and may even stop breathing and die, he said.
Concerns regarding codeine have been mounting for years, but the drug is still available without a prescription in over-the-counter cough formulas from outpatient pharmacies in 28 states and the District of Columbia, the American Academy of Pediatrics (AAP) report noted.
Codeine is also still commonly prescribed to children after surgical procedures such as tonsil and adenoid removal, the report added.
More than 800,000 patients under the age of 11 were prescribed codeine between 2007 and 2011, according to one study cited in the report.
Ear/nose/throat doctors most frequently prescribe liquid codeine/acetaminophen blends, followed by dentists, pediatricians and family physicians, the report found.
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