Dược Động Học :
▧ Absorption :
Absolute bioavailability = 23% with high variability
▧ Volume of Distribution :
* 17 L (low tissue distribution)
▧ Protein binding :
94 - 97% bound to serum proteins, primarily serum albumin
▧ Metabolism :
Valsartan is excreted largely as unchanged drug (80%) and is minimally metabolized in humans. The primary circulating metabolite, 4-OH-valsartan, is pharmacologically inactive and produced CYP2C9. 4-OH-valsartan accounts for approximately 9% of the circulating dose of valsartan. Although valsartan is metabolized by CYP2C9, CYP-mediated drug-drug interactions between valsartan and other drugs is unlikely.
▧ Route of Elimination :
83% of absorbed valsartan is excreted in feces and 13% is excreted in urine, primarily as unchanged drug
▧ Half Life :
The initial phase t1/2 α is < 1 hour while the terminal phase t1/2 β is 5-9 hours.
▧ Clearance :
* 2 L/h [IV administration]
* 4.5 L/h [heart Failure patients receiving oral administration 40 to 160 mg twice a day]