Dextromethorphan and guaifenesin use should be monitored very carefully in people with "very poor metabolizer" CYP2D6 enzyme levels and individuals that are sedated. This mix medication provides a huge median harmful dose (TD50) to median efficient dose (ED50) ratio (or therapeutic index) in these patients. We only use high quality, https://hypebookmarking.com/story17980741/what-does-dextromethorphan-dxm-for-sale-mean