Molecular monitoring of patient response to painkiller drugs

Introduction Non-steroidal anti-inflammatory drugs and opioids are widely prescribed for the treatment of mild to severe pain. Wide interindividual variability regarding the analgesic efficacy and adverse reactions to these drugs (ADRs) exist although the mechanisms responsible for these ADRs are not well understood. Areas covered We provide an overview of the clinical impact of variants in genes related to the pharmacokinetics and pharmacodynamics of painkillers, as well as those associated with the susceptibility to ADRs. In addition, we discuss the current pharmacogenetic-guided treatment recommendations for the therapeutic use of non-steroidal anti-inflammatory drugs and opioids. Expert opinion In the light of the data analyzed, common variants in genes involved in pharmacokinetic and pharmacodynamic processes may partially explain the lack of response to painkiller treatment and the occurrence of adverse drug reactions. The implementation of high-throughput sequencing technologies may help to unveil the role of rare variants as considerable contributors to explaining the interindividual variability in drug response. Furthermore, a consensus between the diverse pharmacogenetic guidelines is necessary to extend the implementation of pharmacogenetic-guided prescription in daily clinical practice. Additionally, the physiologically based pharmacokinetic and pharmacodynamic modeling techniques may contribute to the improvement of these guidelines and facilitate clinician drug dose adjustment.