Interindividual variability of drug transporters: impact on opioid treatment in chronic renal failure

Some transmembrane transporters influence the absorption, the tissue distribution and the elimination of opioids, and their genetic variants may be an important factor in therapeutic efficacy and toxicity. Uptake and efflux transporters may facilitate or limit access of opioids to blood—brain barrier (BBB), modulating pain relief. As renal function is crucial in the metabolism and pharmacokinetic profile of any drug, renal failure and end-stage renal disease may alter drug disposition by affecting protein and tissue binding, and reducing systemic clearance of drugs.