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B Hampel

Publications and source records attributed to B Hampel.

8 recordsLinked to original sources

Pharmacokinetics of FCE 22891, a new oral penem.

FCE 22891 is the oral prodrug of FCE 22101, a new broad-spectrum penem. The pharmacokinetics of FCE 22891 after single-dose administration, its absolute bioavailability, and the effect of food intake on its absorption were investigated in three different randomized crossover studies in healthy volunteers. Drug levels in blood and urine were measured by high-pressure liquid chromatography and bioassay. For optimal comparison of the results of all studies, and since there was good agreement of both methods, only the high-pressure liquid chromatography results are included. The pharmacokinetics of the penem were linear, and its bioavailability after oral administration was 42 +/- 11%. Food intake increased the total area under the curve from 0 h to infinity from 11.9 +/- 3.5 to 14.1 +/- 2.4 mg.h/liter. A specific side effect, i.e., bladder complaints, was registered in some volunteers taking FCE 22891 at doses greater than or equal to 1.0 g.

Administration, Oral

The pharmacokinetics of sultamicillin.

Sultamicillin is a mutual prodrug of ampicillin and sulbactam, a beta-lactamase inhibitor. When administered orally, sultamicillin is readily absorbed and rapidly hydrolyzed to provide high levels of its two constituents in the peripheral circulation. Peak serum concentrations of ampicillin are achieved that are approximately three and one-half times those obtained with an equivalent amount of oral ampicillin. Equimolar concentrations of sulbactam are also provided, with both ampicillin and sulbactam being widely distributed among various body fluids and tissues. The pharmacokinetic parameters of the two components are similar, both being eliminated primarily by renal excretion. Although the elimination half-lives of ampicillin and sulbactam are each approximately 1 hour, the high serum concentrations achieved coupled with their synergistic bactericidal activity permit twice-daily dosing.

Amoxicillin

Comparative pharmacokinetics of sulbactam/ampicillin and clavulanic acid/amoxycillin in human volunteers.

In this study, the pharmacokinetic parameters of 2 different beta-lactamase inhibitors (sulbactam and clavulanic acid) in combination with 2 different aminobenzylpenicillins (ampicillin and amoxycillin) were compared. The study involved 10 healthy volunteers who received sulbactam 250 mg plus ampicillin 500 mg intravenously, clavulanic acid 100 mg plus amoxycillin 500 mg intravenously, sultamicillin equivalent to sulbactam 294 mg plus ampicillin 440 mg orally, and clavulanic acid 125 mg plus amoxycillin 500 mg orally in a crossover, randomised trial. Serum and urine concentrations of ampicillin, amoxycillin and clavulanic acid were assayed by agar diffusion test, and the concentrations of sulbactam by gas chromatography with mass spectrometry. Pharmacokinetic parameters were calculated according to open 1- and 2-compartment models. Test results showed that the addition of sulbactam significantly increases the bioavailability of oral ampicillin when the 2 drugs are administered in the form of the prodrug sultamicillin. Also, sulbactam does not interfere with the kinetics of intravenous ampicillin but increases the absorption of oral ampicillin.

Administration, Oral

Comparative pharmacokinetics of ceftriaxone after subcutaneous and intravenous administration.

The pharmacokinetics of ceftriaxone (CRO) after subcutaneous and intravenous administration was studied in 10 healthy volunteers (5 males, 5 females, age 22-43 years, body weight 64.3 +/- 9.5 kg). Each of them received 2.0 g CRO i.v., and then 0.5 g i.v. and 0.5 g CRO s.c. in a randomized cross-over design. Subcutaneous administration of ceftriaxone was tolerable in combination with lidocaine. Serum and urine concentrations were determined by high performance liquid chromatography and for comparison with a bioassay. Mean serum concentrations were high after intravenous administration: 258 +/- 40 mg/1 (0 min, 2 g i.v.) resp. 84 +/- 40 mg/1 (0 min, 0.5 g i.v.). They declined to 11.6 +/- 4.2 mg/1 (2 g) resp. 6.5 +/- 2.2 mg/1 (0.5 g i.v.) within 24 h. Following subcutaneous application peak serum concentrations of 37.1 +/- 5.6 mg/1 were found after 138 +/- 49 min and a mean serum concentration of 6.6 +/- 1.6 mg/1 after 24 h. Concentrations of free ceftriaxone, determined by ultrafiltration, were 9.2 +/- 2.7% of total concentrations from 25 to 200 mg/1. Cumulated urine recoveries over a period of 24 h were: 51.2 +/- 8.9% (2 g i.v.), 47.1 +/- 7.9% (0.5 g i.v.) and 39.7 +/- 9.5% (0.5 g s.c.). There was no evidence for the presence of a microbiologically active metabolite in urine. Comparison of pharmacokinetic parameters for the 0.5 g dose did not show relevant differences between intravenous and subcutaneous administration (using an open two-compartment model): t beta 1/2 (min) 514 +/- 104 (s.c.), 592 +/- 133 (i.v.), VD,Area (1) 11.9 +/- 3.8 (s.c.), 13.3 +/- 3.8 (i.v.) and AUCtot (mg X h/1) 515 +/- 106 (s.c.) and 549 +/- 125 (i.v.). Bioavailability of the subcutaneous application was 0.96 +/- 0.26. For the 2 g i.v. dose the known nondosis-dependent kinetics was observed. Subcutaneous administration of ceftriaxone appears to be a possible alternative to the intravenous route in selected clinical situations or cases.

Adult

Pharmacokinetics of temocillin in volunteers.

The pharmacokinetics of temocillin, a new semisynthetic parenteral penicillin, were studied in 10 healthy volunteers. Doses of 0.5, 1.0, and 2.0 g were administered by intravenous bolus injection at weekly intervals, and serum and urine samples were assayed by an agar diffusion method. Mean peak serum concentrations were: 77.9 (+/- 28.4) mg/L (0.5 g), 160.8 (+/- 58.2) mg/L (1.0 g), and 236.1 (+/- 93.3) mg/L (2.0 g), with serum concentrations still being measurable after 12 hours for all doses [7.9 (+/- 3.7) mg/L, 12.9 (+/- 5.2) mg/L, 14.8 (+/- 6.3) mg/L]. According to a 2-compartment open model, the mean terminal half-lives of 0.5, 1.0, and 2.0 g doses were 5.2 (+/- 0.3), 5.0 (+/- 0.2), and 5.0 (+/- 0.2) hours, respectively. The total volume of distribution averaged 0.15 (+/- 0.01), 0.17 (+/- 0.01), and 0.24 (+/- 0.01) L/kg bodyweight, respectively, mean renal clearances were 18.5 (+/- 3.2), 19.6 (+/- 5.0), and 29.8 (+/- 2.6) ml/min, respectively, and the area under the serum concentration time curve (AUC) was 344.1 (+/- 18.7), 573.3 (+/- 27.8), and 784.5 (+/- 47.1) mg X h/L, respectively. At 74 (+/- 12.9)%, the 24-hour urinary recovery was highest for the low dose, followed by 68.1 (+/- 6)% for the 2.0 g dose, and 66.1 (+/- 16.8)% for the 1.0 dose. No untoward side effects were recorded. Thus, temocillin appears to be a penicillin with a prolonged half-life and high AUC.

Adult