Pharmacokinetics of Lincomycin Hydrochloride and Spectinomycin Sulfate Suspension for Injection in Swine

The lincomycin hydrochloride and spectinomycin sulfate suspension was injected into the neck muscle in 8 healthy pigs(5 mg·kg^-1 lincomycin，10 mg·kg^-1 spectinomycin). The concentrations of lincomycin and spectinomycin in plasma were determined by HPLC with UV detection, respectively. The plasma concentration-time data were fit to a non-compartmental analysis based on statistical moment theory. The main pharmacokinetic parameters of lincomycin were as follows: k_e=(0.21±0.01) h^-1；t_1/2β=（3.38±0.09）h；t_max=（0.29±0.02）h；C_max=（5.15±0.18）μg·mL^-1；AUC_0～LOQ=（10.27±0.38）μg·mL^-1·h；MRT=（3.52±0.11）h；Cl_B/F=（0.46±0.01）L·h^-1·kg^-1；V_Z/F=（2.26±0.12）L·kg^-1, whereas, those of spectinomycin were: k_e=(0.43±0.01) h^-1；t_1/2β=（1.64±0.06）h；t_max=（0.44±0.03）h；C_max=（20.05±0.70）μg·mL^-1；AUC_0～LOQ=（51.82±0.98）μg·mL^-1·h；MRT=（2.39±0.04）h；Cl_B/F=（0.19±0.01）L·h^-1·kg^-1；V_Z/F =（0.46±0.02）L·kg^-1. It was noted that both lincomycin hydrochloride and spectinomycin sulfate were rapidly absorbed and eliminated, however, the latter was more slowly absorbed but more rapidly eliminated after the intramuscular administration of lincomycin hydrochloride and spectinomycin sulfate suspension in pigs.