[Teratologic studies in rabbits and rats with the morphine derivative codeine (author's transl)]

Codeine was administered to rabbits and rats during the organogenetic phase (days 6--18 and 6--15, resp.) in oral doses of 5, 12.5 and 30 mg/kg and 10, 35 and 120 mg/kg, resp. The tests in rabbits yielded no indication of a teratogenic or embryolethal action of the substance under investigation. Even in the experiments on rats no teratogenicity could be realised. The highest dose of 120 mg/kg led to an increased mortality of rat embryos around the time of implantation. As this dose was toxic even to adult rats the described experiments give no indication of an increased risk during pregnancy.