The Clinical Pharmacogenetics Implementation Consortium (CPIC) has published updates to the guidelines for the use of genetic test results for cytochrome P450-2D6 (CYP2D6) in codeine dosing. The 2014 update is now available online, as an accepted article preview.
Alternate analgesics are recommended for CYP2D6 ultrarapid and poor metabolizers. Label recommended age- or weight-specific codeine dosing is warranted for CYP2D6 extensive and intermediate metabolizers. However, patients with the intermediate metabolizer phenotype should be monitored closely for less than optimal response and should be offered an alternative analgesic if required.
This updated guideline extended Table 2, which summarizes codeine therapy recommendations based on CYP2D6 phenotype, to include considerations regarding the use of alternative opioids.
The guideline supplements include updates on the literature review, the CYP2D6 genetic testing interpretation, the frequencies of CYP2D6 alleles in major race/ethnic groups, and evidence linking CYP2D6 genotype to phenotype.
For details see the CPIC guidelines and supplements for CYP2D6 and codeine.