Effect of sulphadoxine-trimethoprim combination on some pharmacokinetic aspects of sulphadoxine in goats

Abstract

Some pharmacokinetic aspects of sulphadoxine alone and sulphadoxine-trimethoprim (TMP) combination were studied in goats following single intravenous (i.v) and intramuscular (i.m) administration of 15 mg kg–1 b.wt. After i.v injection the serum sulphadoxine concentration time course was best described by two compartment-open model with distribution half-lives (t0.5(α)) 2.48 and 2.31 h., elimination (t0.5(β)) half-lives 23.10 and 24.75 h., total body clearance (ClB) 0.076 and 0.073 L kg-1 h.-1 and steady state volume of distribution (Vdss) 368.54 and 411.73 ml kg-1 for sulphadoxine alone and sulphadoxine-trimethoprim combination, respectively. After i.m administration the mean peak serum concentrations (Cmax) 25.69 and 33.31 ug ml–1 were achieved after maximum time (tmax) of 3.09 and 2.79 h. for sulphadoxine alone and sulphadoxine- trimethoprim combination, respectively. The absorption half-lives (t0.5(ab)) were 0.58 and 0.42 h., respectively. It is concluded that a combination of sulphadoxine and TMP can provide a synergistic level for both antimicrobials and thus be a useful combination in the treatment of various goat diseases.