RESUMEN
Objective: The study was conducted to determine the pharmacokinetis of diclofenac in healthy male volunteers so as to establish therapeutic norms. Setting: Department of Chemistry, Physiology and Pharmacology University of Agriculture Faisalabad. Period: During the year 2003
Material and Methods: The concentrations of diclofenac sodium in the plasma of 10 male volunteers were determined by HPLC analysis following oral administration of 50 mg capsules
Results: The diclofenac molecule was found to absorb rapidly and the concentration was detectable even after 10 minutes of the drug intake. The mean+/-SD values for the absorption kinetic parameters were for time to peak concentration [T max] 0.53+/-0.05 hours [range 0.42 to 0.56 hours], C max 2.52+/-0.17 mg/L [range 2.25 to 2.72 mg/L], absorption half-life 0.21+/-0.06 hours [range 0.08 to 0.28 hours] and the absorption rate constant [Ka] 3.77+/-1.75 1/h [range 1.75 to 8.16 1/h]. The disposition kinetics parameters revealed mean+/-SD values for AUC 4.31+/-0.45 h. mg/L and ranged between 3.66 to 5.01 h. mg/L, c Volume of the Central Compartment [V] 9.41+/-2.12 L range 7.08 to 12.79L, Volume of distribution 46.34+/-20.37 liter ranged 32.64 to 79.18L, distribution half-life 0.32 +/- 0.10 hours range 0.19 to 0.47 hours and elimination half-life 2.80 +/- 1.35 hours range 1.61 to 5.58 hours and the mean residence time [MRT] 1.94+/-2.62 hours range 1.86 to 3.87 hours
Conclusions: Variable parameters were observed for disposition kinetics of diclofenac in this pilot study indicating the need for dosage adjustment and its evaluation