N&PD Moderators: Skorpio Forums Media, Science and Research Neuroscience and Pharmacology Discussion The CYP2D6 mediated o-demethylation of codeine and the 'ceiling effect' JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding. You are using an out of date browser. It may not display this or other websites correctly.You should upgrade or use an alternative browser. Members who reacted to message #4 All (1) Like (1) 3 Oct 27, 2024 3DQSAR Bluelighter Messages 395 Reaction score 204 Points 15 Loading… Forums Media, Science and Research Neuroscience and Pharmacology Discussion The CYP2D6 mediated o-demethylation of codeine and the 'ceiling effect'