Coadministration has not been studied but based on metabolism and clearance a pharmacokinetic interaction is unlikely. Ketorolac is partly eliminated renally and via hepatic metabolism by CYP2C8, CYP2C9 and UGT2B7. No pharmacokinetic interaction is expected with emtricitabine or tenofovir-DF, however, coadministration could potentially result in increased risk of nephrotoxicity. Cases of acute renal failure after initiation of high dose or multiple NSAIDs have been reported in patients treated with tenofovir-DF and with risk factors for renal dysfunction. The risk is increased if an NSAID is used for a long duration, if the patient has a pre-existing renal dysfunction, has a low body weight, or receives other drugs that may increase tenofovir exposure. Alternatives to NSAIDs should be considered in patients at risk for renal dysfunction. If emtricitabine/tenofovir-DF is co-administered with an NSAID, renal function should be monitored adequately.