Dược Động Học :
▧ Absorption :
Variable, yet relatively rapid rate of absorption with a time to peak concentration of 2.8-3.9 hours. Food has no effect on the bioavailability of zonisamide.
▧ Volume of Distribution :
* 1.45 L/kg
▧ Protein binding :
40% (at concentrations of 1.0-7.0 µg/mL)
▧ Metabolism :
Primarily hepatic through cytochrome P450 isoenzyme 3A4 (CYP3A4). Undergoes acetylation and reduction, forming N-acetyl zonisamide, and the open-ring metabolite 2–sulfamoylacetyl phenol, respectively.
▧ Route of Elimination :
Zonisamide is excreted primarily in urine as parent drug and as the glucuronide of a metabolite.
▧ Half Life :
▧ Clearance :
* 0.30 - 0.35 mL/min/kg [patients not receiving enzyme-inducing antiepilepsy drugs (AEDs)]
* 0.35 - 0.5 mL/min/kg [Concomitant administration of phenytoin and carbamazepine]