Codeine use by nursing mothers may harm babies

NEW YORK Medicinal use of codeine by breast-feeding mothers may harm their babies’ health, according to a recent Canadian study.

In some women, genetic factors cause their bodies to metabolize codeine into morphine faster than others, increasing the babies’ risk of morphine overdose. Over time, buildup of morphine in the babies’ bodies can cause sleepiness, breathing problems and death.

The study, published online Aug. 20 in the journal Clinical Pharmacology and Therapeutics, looked at DNA samples from 72 Canadian mothers who used codeine after giving birth between 2004 and 2007 and also administered a telephone survey of the mothers to determine their health and their children’s health before, during and after the use of codeine. Almost a quarter of the babies experienced nervous system depression, evidenced by reduced alertness, while their mothers used codeine.

Two of the mothers had the genetic predisposition to overproduce morphine, and one of their babies died.