Pharmacokinetics of diclofenac sodium injection in swine

The pharmacokinetics of a diclofenac sodium was investigated in swine.A single intravenous (i.v.) or intramuscular (i.m.) injection of 5% diclofenac sodium (concentration = 2.5 mg • kg -1 ) was administered to 8 healthy pigs according to a two-period crossover design.The pharmacokinetic parameters were calculated by non-compartmental analysis with DAS2.1.1 software.After a single i.v.administration, the main pharmacokinetic parameters of diclofenac sodium injection in swine were as follows: the elimination half-time (T 1/2β ) was 1.32±0.34h; the area under the curve (AUC) was (55.50±5.50μg • mL -1 h; the mean residence time (MRT) was 1.60±0.28h; the apparent volume of distribution (V d ) was 0.50±0.05L • kg -1 ; and the body clearance (CL B ) was 0.26±0.04L • (h • kg) -1 .After the single i.m. administration, the pharmacokinetic parameters were as follows: peak time (T max ) was 1.19±0.26h; and peak concentration (C max ) was 11.61±5.99μg mL -1 .The diclofenac sodium has the following pharmacokinetic characteristics in swine: rapid absorption and elimination; high peak concentration; and bioavailability.