27/03/2026
A pivotal Lancet case report suggesting that codeine given to breastfeeding mothers could trigger opioid overdoses in babies is facing demands for investigation.
The 2006 report came under scrutiny after a member of the original research team wrote to the journal on 20 January 2026 alleging misconduct by the team’s leader.
The Lancet has now issued an expression of concern over the paper and requested an investigation by Toronto’s Hospital for Sick Children, widely known as SickKids, where the paper was written under the leadership of the pharmacologist Gideon Koren.
Koren’s work has come under intense focus in recent weeks after it emerged that a separate case report describing an overdose in another baby that appeared to support the Lancet paper’s hypothesis was entirely fictitious.2 That report was written by Koren in Paediatrics & Child Health, the journal of the Canadian Paediatric Society, but no mention was made of its fictitious nature and it was accepted as describing a real event.
Koren’s paper was part of a tsunami of corrections issued by the journal for a total of 138 case reports by various authors published over a 25 year period noting that each clinical vignette “describes a fictional case, created as a teaching tool.”
The 2006 Lancet article, which has been cited 822 times, described a case in which a 12 day old baby died from opioid overdose while his mother was taking codeine for postpartum pain
https://www.bmj.com/content/392/bmj.s498
No change in MHRA recommendations at present
