Abstract: The pharmacokinetics of a sustained- release formulation and an enteric-coated tablet of diclofenac sodium were studied on 8 healthy male volunteers in an open, randomized crossover study. Drug level in serum was assayed by HPLC method. The changes in serum concentration were conformed to a l-compartment open model. The t1/2 (Ke) averaged 2.15±0.17 and 11.60±l.95 h, and the areas under the drug concentration curves were 5.87±0.67 and 5.55±0.57 μg·h/ml for enteric-coated and sustained-release tablet of diclofenac sodium, respectively. The mean relative bioavailability of sustained-release tablet was 0.95 to that of enteric-coated tablet.

Key words: Diclofenac sodium, Pharmacokinetics, Sustained-release, Enteric-coated, Rela tive bioavailability