A Weibull distribution model for intradermal administration of ceftazidime.

The pharmacokinetics of 1 g of ceftazidime administered intradermally was studied in seven healthy volunteers. The objective of the present study was to find the most appropriate mathematical model to describe the drug intake process. The concentration of ceftazidime in plasma was measured by HPLC. The disposition of the drug was described by a one-compartment pharmacokinetic model, with drug intake occurring by different processes: a zero-order process due to the administration and a first-order intake from the injection site to the systemic circulation. The Weibull model was considered as an approximation of the overall process. The mean Weibull parameters were td (time necessary to transfer 63% of the administered drug into the systemic circulation) of 2.75 +/- 0.75 h, and f (shape) of 1.04 +/- 0.15. The mean elimination half-life was 2.0 +/- 0.4 h. The area under the concentration versus time curve obtained in this study (139 +/- 46 mg.h/L) is very near to literature values reported after single intravenous doses of 1 g of ceftazidime, suggesting that the bioavailability of ceftazidime after intradermal administration may be approximately 100%. Moreover, the mean peak plasma concentration (37 +/- 16 mg/L) is in the same range as that reported in the literature after intramuscular administration of a single dose of 1 g.

[Acute epididymitis and antibiotherapy. Measurement of the epididymal diffusion of pefloxacin]. / Epididymites aiguës et antibiothérapie Mesure de la diffusion épididymaire de la péfloxacine.

Acute epididymitis is a common infection in the young sexually active adult. Etiologically, the organisms most frequently found are Chlamydia trachomatis, Neisseria gonorrhea and gram negative bacilli. Pefloxacin is a novel quinolone whose antibacterial spectrum and bactericidal activity allow it to be considered for use in the treatment of orchitis and epididymitis Prior to clinical study the authors investigated the degree of epididymal diffusion of Pefloxacin. Ten subjects underwent extraction of an epididymal sample by direct access to the epididymis through a transverse scrotal incision under peridural anesthesia. Three days before surgery, Pefloxacin was administrated at the rate of 400 mg every 12 hours by the oral route. On the day of the operation, the subject receive a 400 mg infusion over one hour, 2 hours before epididymal biopsy. Blood specimens were also extracted. Pefloxacin assays were performed by HPLC following a method derived from that of Montay. The trough concentration of Pefloxacin inhibiting 90% of sensitive strains (MIC 90) is less than or equal to 2 micro-g/ml. The majority of sensitive organisms have minimum bactericidal concentrations equal to twice the MIC 90. The epididymal concentrations that the authors measured are situated at values of 8.15 to 21.80 miro-g/g tissue (mean 13.44). These data allow the use of Pefloxacin to be considered an option in the treatment of epididymitis.