[Genetics, pain and analgesia]

Abstract

Genomic variations influencing nociceptive sensitivity and susceptibility to pain conditions, as well as responses to pharmacotherapy of pain are currently under investigation. Candidate genes involved in pain perception, pain processing and pain management such as (opioid) receptors, transporters and other targets of pharmacotherapy are discussed. Drug metabolizing enzymes represent a further major target of ongoing research in order to identify associations between an individual's genetic profile and drug response (pharmacogenetics). Polymorphisms of the cytochrome P 450 enzymes influence analgesic efficacy of codeine, tramadol and tricyclic antidepressants (CYP2D6). Blood levels of some non-steroidal anti-inflammatory drugs (NSAIDs) are dependent on CYP2C9 activity, whereas opioid receptor polymorphisms are discussed with respect to differences in opioid-mediated analgesia and side-effects. Pharmacogenetics is seen as a potential diagnostic tool for improving patient therapy and care and will contribute to a more individualized drug treatment in the future.