Using codeine to treat pain in some breastfeeding mothers may be risky for infants, according to a new study.
Researchers at The Hospital for Sick Children have found the codeine in some pain relief drugs can be harmful and possibly even fatal for infants when taken by some mothers.
The study was prompted by the death of an infant who suffered a morphine overdose through breast milk.
Rani Jamieson's son Tariq died in 2005 when he was just 12 days old.
"That evening when he stopped breathing at home . . . it was like, 'what's happening? This can't be happening!'" she told CTV News.
Doctors had given Jamieson Tylenol 3, which contains codeine. Unknowing that she was one of the small percentage of women whose bodies convert codeine into morphine, she breastfed her son, causing an overdose of morphine.
"I lose a child that I was so prepared for and for something I could have avoided," she said. "I would not have taken the drugs . . . I would not have breastfed and taken the drug."
Jamieson has launched a class-action suit against the makers of Tylenol 3.
One of the study's researchers says that mothers need to be informed about codeine's potentially fatal side-effects.
"I don't think there is a reason to be scared but there is a reason to be informed," Dr. Gideon Koren of The Hospital for Sick Children, told CTV News. "I don't think people should be scared but like many other drugs, women and doctors should be aware that something we thought was safe - may not be safe."
Codeine, found in painkillers like Tylenol 3, had been recommended by the American Academy of Pediatrics for use in women who were breastfeeding.
Codeine must be metabolized by the body into morphine in order for it to begin relieving pain. However, some people have a rare genetic condition which causes them to transform it much more quickly.
Women with this genetic abnormality who take codeine while breastfeeding then expose infants to high, possibly even toxic levels of morphine through their breast milk.
About five per cent of women have this genetic defect -- meaning about 5,000 Canadian newborns are at risk.
Babies exposed to morphine can experience central nervous system depression, including symptoms like difficulty breathing, poor feeding and lethargy. Mothers with the genetic abnormality may experience similar symptoms themselves.
"The good news is that those breastfeeding children who were exposed to these high levels of morphine showed dramatic improvement once they were taken off the morphine tainted breast milk," Koren said in a press release.
"By removing the exposure, most children will demonstrate a complete reversal of symptoms and show no long-term adverse effects."
With a report from CTV's Scott Laurie
