THE widely used painkiller codeine doesn’t work in some people and can be fatal in others, so its use should be halted, say researchers at the University of British Columbia in Vancouver, Canada.

Codeine works by being metabolised to morphine in the body, but the extent of that metabolism depends on a person’s genetic make-up, so the amount of morphine produced varies.

In an editorial published in the Canadian Medical Association Journal this week, Stuart MacLeod and Noni MacDonald say the problem is especially relevant for infants, citing examples of two children who died after being given codeine following …