Absorption:Absorption is rapid. T max is approximately 1.7 h. C max and AUC are approximately proportional in doses from 15 to 60 mg single dose administration. Absolute bioavailability is over 80%. C max and AUC decrease 50% if given 30 min after food.
Distribution:Protein binding (97%) is constant over the concentration range of 0.05 to 5 mcg/mL.
Metabolism:Extensively metabolized in the liver. Metabolites are hydroxylated sulfonyl and sulfone derivatives (very little activity).
Elimination:Significant biliary excretion of the metabolites. Mean t ½ is 1.9 to 2.9 h.
Special Populations: Hepatic Function Impairment: Mean t ½ prolonged to 3.2 to 7.2 h and AUC increased up to 500%; dose reduction is recommended in severe hepatic disease.
Elderly:Cl is decreased with t ½ increasing approximately 50% to 100%. Because mean t ½ remains between 1.9 to 2.9 h, repeated once daily dosing does not accumulate; no adjustment needed.
|