A.M. Baars

Pharmacokinetics, renal clearance and metabolism of ciprofloxacin following intravenous and oral administration to calves and pigs

The pharmacokinetics of ciprofloxacin, a quinoline derivative with marked bactericidal activity against gram-negative bacteria, was studied in calves and pigs following intravenous and oral administration. Ciprofloxacin was rapidly and well distributed in the body, exhibited a short elimination half-life of 2.5 h in both species, and was rapidly absorbed after oral administration (Tmax:2 to 3 h). The oral bioavailability in calves was 53 +/- 14% and for 1 pig 37.3%. The renal clearance of the unbound ciprofloxacin for both species was of the same order, indicated a predominantly tubular secretion pattern, and accounted for about 46% of the total drug elimination. No complete drug mass balance could be demonstrated. Small amounts of two metabolites were detected in the urine of calves, but not in pig urine.

Determination of trimethoprim and sulfamethoxazole (co-trimoxazole) in body fluids of man by means of high-performance liquid chromatography

A high-performance liquid chromatographic method for the determination of trimethoprim, sulfamethoxazole and its metabolite and a series of structurally related sulfonamides is described. The half-life time of elimination of sulfamethoxazole and its metabolite N4-acetylsulfamethoxazole is 9 h for both compounds. The renal excretion rate of sulfamethoxazole depends strongly on the urinary pH. The renal excretion rate of the metabolite N4-acetylsulfamethoxazole is not dependent on the urinary pH.

Pharmacokinetics of Sulphamethoxazole in Man: Effects of Urinary pH and Urine Flow on Metabolism and Renal Excretion of Sulphamethoxazole and its Metabolite N4-Acetylsulphamethoxazole

SummaryA high performance liquid chromatography method for the determination of sulphamethoxazole and its metabolite N4-acetylsulphamethoxazole is described. The renal excretion rate and cumulative renal excretion of sulphamethoxazole is markedly influenced by urinary pH. With constant urinary pH, the renal excretion rate and the renal clearance of sulphamethoxazole is dependent on the urine flow. The renal clearance of the metabolite N4-acetylsulphamethoxazole is not influenced by urinary pH or urine flow.No clear acetylator phenotype could be detected in the group of volunteers studied. The extent of acetylation depends on the amount of sulphamethoxazole available for acetylation, thus indirectly on the urine pH and flow.

High-performance liquid chromatography and preliminary pharmacokinetics of articaine and its 2-carboxy metabolite in human serum and urine

T.B. VREE* Department of Clinical Pharmacy and Department of Anesthesiology, Sint Radboud Hospital, University of Nijmegen, Nijmegen (The Netherlands) A.M. BAARS Department of Clinical Pharmacy, Sint Radboud Hospital, University of Nijmegen, Nijmegen (The Netherlands) G.E.C.J.M. VAN OSS Department of Anesthesiology, Hervormd Diaconessen Huis, Arnhem (The Netherlands) and L.H.D.J. BOOIJ Department of Anesthesiology, Free University Hospital, Amsterdam (The Netherlands)

Clinical effects and pharmacokinetics of articainic acid in one volunteer after intravenous administration

Articainic acid, a major metabolite of articaine, was administered to a volunteer. Since the renewed interest in the utilization of articaine in epidural anaesthesia, it has been important to assess the clinical effects of this metabolite. It was noted that articainic acid had no effect on EEG, ECG, blood pressure and heart rate. Pharmacokinetic parameters are given.

Hydroxylation and oxidation of nalidixic acid in the turtle Pseudemys scripta elegans.

The turtle Pseudemys scripta elegans hydroxylates nalidixic acid into 7-hydroxynalidixic acid; this latter metabolite is oxidised into 7-carboxynalidixic acid. The elimination half-life of nalidixic acid in the turtle is 30 h. No glucuronides of nalidixic- and 7-hydroxynalidixic acid are formed, as they are in man.