1. US Food and Drug Administration. FDA Drug Safety Communication: safety review update of codeine use in children; new boxed warning and contraindication on use after tonsillectomy and/or adenoidectomy. http://www.fda.gov/Drugs/DrugSafety/ucm339112.htm. Accessed October 29, 2014.
2. Health Canada. Health Canada’s review recommends codeine only be used in patients aged 12 and over. http://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2013/33915a-eng.php. Accessed October 29, 2014.
3. European Medicines Agency. Press release. Restrictions on use of codeine for pain relief in children: CMDh endorses PRAC recommendation. http://www.ema.europa.eu/ema/index.jsp?curl=pages/news_and_events/news/2013/06/news_detail_001829.jsp&mid=WC0b01ac058004d5c1. Accessed October 29, 2014.
4. Codeine, ultrarapid- metabolism genotype, and postoperative death;Ciszkowski;N Engl J Med,2009
5. Pharmacogenetics of morphine poisoning in a breastfed neonate of a codeine-prescribed mother;Koren;Lancet,2006