Comparison of Bioavailability and Pharmacokinetics of Diclofenac Sodium and Diclofenac Potassium in Healthy and Escherichia coli Induced Febrile Rabbits

Diclofenac sodium and diclofenac potassium in tablet dosage form were tested for their bioavailability and disposition kinetics in a group of 18 rabbits in normal and Escherichia coli induced febrile condition with a washout period of 7 days. Biochemical and physiological parameters were measured in both normal and febrile state. Diclofenac levels in plasma were determined using a reversed-phase HPLC method. Primary kinetic parameters i.e. AUC0-∞, Cmax, tmax and other disposition kinetics, were obtained with non-compartmental procedure. The values of physiological and biochemical parameter were significantly (p<0.05) low in febrile rabbits as compared to that of normal animals. The drug concentration levels and pharmacokinetics of orally administered diclofenac sodium and diclofenac potassium were changed during fever. The comparison of diclofenac sodium and diclofenac potassium in normal and febrile conditions showed significantly (p<0.05) increased level of diclofenac potassium in both conditions normal & febrile.