Coadministration has not been studied. Furosemide is glucuronidated mainly in the kidney (UGT1A9) and to a lesser extent in the liver (UGT1A1). A large proportion of furosemide is also eliminated unchanged renally (via OATs). In vitro data indicate that furosemide is a weak inhibitor of the renal transporters OAT1/OAT3. No interaction with emtricitabine is expected and any effect on renal elimination of tenofovir is likely to be limited. No a priori dosage adjustment is recommended.