From: Pharmacogenomic considerations in the opioid management of pain
Gene | Variant | Analgesics affected | Consequence of genetic variation |
---|---|---|---|
ABCB1 | 3435C>T | Morphine | Homozygous variants cause increased efficacy |
CYP2D6 | 1846G>A, 2549A>del | Codeine, oxycodone, tramadol | Poor metabolizers (PM; variants) have more adverse drug reactions and less efficacy |
UGT2B7 | -840G>A, 802C>T; *2 | Morphine | Homozygous variants require lower doses of morphine for efficacy; UGT2B7*2 variants have less side effects (nausea) with morphine |
COMT | 1947G>A, (Rs4680) | Morphine | Homozygous variants have a three- to fourfold decrease in COMT activity; wild-type patients require higher doses of morphine for efficacy than variant patients |
OPRM1 | 118A>G | Morphine, M6G | Homozygous variants cause decreased effectiveness and increased dose requirements |