Absorption Well absorbed. T max is 31.3 h (active isomer). C max is 0.77 mcg/mL (active isomer).
Distribution 96% protein bound.
Metabolism Undergoes stereospecific metabolism. The S-isomer (inactive) is metabolized by glucuronidation. The R-isomer (active) undergoes glucuronidation but is predominantly oxidized to an inactive metabolite.
Elimination Eliminated in urine and feces; t ½ is 5.8 days (active isomer).
Special Populations Hepatic Function Impairment The t ½ of the R-isomer is increased about 76% in patients with severe liver disease. No dosage adjustment is necessary.
|