Biomedical subjects

M J Nieto

Publications and source records attributed to M J Nieto.

22 records · Page 2Linked to original sources

PubMed1983

Elimination of cefroxadine (CGP-9000) from patients undergoing dialysis.

The pharmacokinetics of cefroxadine was studied in 17 patients with terminal renal impairment, 10 of whom were undergoing 5 h dialysis sessions. The antibiotic was administered as a single oral dose of 500 mg. Cefroxadine followed a single compartment open kinetic model. During the interdialysis period in patients with terminal renal impairment, an average Cmax of 26.59 micrograms/ml and a tmax of 3.65 h were reached, which are greater than in patients with normal renal function. The serum half-life was reduced from 23.55 h in the interdialysis periods to 3.40 h during the dialysis sessions. The average extraction coefficient was 0.249. It is recommended that a 500 mg dose cefroxadine should be administered at the end of each dialysis session if the interdialysis period is 48 h.

Adolescent↗

PubMed1980

Disposition of cefoxitin in the elderly.

The pharmacokinetics off cefoxitin were studied after a single i.v. and i. m. dose of 15 mg/kg of cefoxitin to 15 younger people (15-55 years) and to 16 geriatric patients (66-94 years). The kinetics of the antibiotic follow an open two-compartment model for both administration routes. After i.m. administration of the antibiotic, there are modifications in the distribution with respect to i.v. administration, and there is a decrease in beta K21 and as a consequence, an increase in Vp. In geriatric patients, pharmacokinetic modifications take place with respect to those recorded in the younger people in both administration routes, there being a decrease in the following pharmacokinetic parameters: alpha, beta, K12, K21, K13 and Clp, together with an increase in the apparent distribution volume Vdss. A linear relationship has been established between the constant beta and the age of the patient. In spite of the pharmacokinetic modifications observed as a function of age, given the wide safety margin of the antibiotic, it is not necessary to modify the dosage regimen of cefoxitin in geriatric patients.

Adolescent↗

PubMed1980

The influence of ascites on the pharmacokinetics of amikacin.

The pharmacokinetics of Amikacin are studied after the administration of 7.5 mg/kg body weight to 10 ascitic patients diagnosed with various hepatic disorders. The antibiotic was determined microbiologically in plasma and in the ascitic fluid. The antibiotic follows a two-compartment kinetic model, and it may be seen that once the rapid disposition phase has ended, an inflexion in the plasma-time levels curve takes place, with a passing increase in the plasma concentrations. From the pharmacokinetic study of Amikacin in these patients, it may be deduced that the ascitic liquid forms part of the central compartment for the effects of distribution, though not for the effects of elimination. The plasma half-life of the slow disposition phase is analogous to that obtained from non-ascitic patients with normal renal function. In one of the patients, the antibiotic was administered intraperitoneally; following this, the plasma concentrations of Amikacin were detected. In the last of the 10 patients included in the survey, the evolution of the plasma concentrations of the antibiotic were studied while the patient was undergoing a multiple dosage regimen with the aim of determining the accumulation of Amikacin in the ascitic fluid. A dosage regimen of multiple doses is programmed which should guarantee the efficiency and safety of the antibiotic.

Amikacin↗

PubMedDate not supplied

Isolation and identification of the N-oxide metabolite of picobenzide in human urine.

The possible presence of metabolites was investigated in the urine of 14 patients treated with N-(4-picolyl) 3,5 dimethyl benzamide (picobenzide) after an i.v. dose of 10 mg/Kg. The metabolites formed were isolated by liquid-liquid extraction processes and chromatographic techniques. The main metabolite of this neuroleptic agent is the N-oxide derivative, which appears in urine together with the unaltered drug. Identification of the metabolite was made by I.R. spectroscopy, nuclear magnetic resonance (NMR) and mass spectroscopy. Its structure was confirmed by comparison with the metabolite obtained by synthesis.

Adult↗