Premium
Pharmacokinetics of Amikacin and Cephalothin in Bedridden Elderly Patients
Author(s) -
YASUHARA HAJIME,
KOBAYASHI SHINICHI,
SAKAMOTO KOJI,
KAMIJO KAZUYA
Publication year - 1982
Publication title -
the journal of clinical pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.92
H-Index - 116
eISSN - 1552-4604
pISSN - 0091-2700
DOI - 10.1002/j.1552-4604.1982.tb02693.x
Subject(s) - amikacin , medicine , pharmacokinetics , volume of distribution , impaired renal function , renal function , excretion , surgery , antibiotics , chemistry , biochemistry
The pharmacokinetics of amikacin (5.5 mg/kg intramuscularly) and cephalothin (1000 mg/body intravenously) in bedridden elderly patients were studied in comparison with those in healthy volunteers. The eliminations of amikacin and cephalothin from the plasma followed the course of a one‐compartment open model. For amikacin, five healthy volunteers, elimination rate constant K el was 0.396 hr −1 biologic half‐life t ½ was 1.80 hour, volume of distribution V d was 0.201 l./kg; in five bedridden elderly patients, K el was 0.208 hr −1 , t ½ was 3.55 hours, V d was 0.376 l./kg. Cumulative renal excretion of amikacin in 8 hours was 44 per cent of the total dose in bedridden elderly patients and 69 per cent in healthy volunteers. For cephalothin, in seven healthy volunteers, K el was 0.0353 min −1 , t ½ was 19.7 min, V d was 0.176 l./kg; in four bedridden elderly patients, K el was 0.0127 min −1 , t ½ was 56.4 min, V d was 0.283 l./kg. Cumulative renal excretion of cephalothin reached a plateau by 4 hours of 40.8 per cent of the total dose in bedridden elderly patients and of 56.7 per cent in healthy volunteers. These results suggest that in bedridden elderly patients decreased renal excretion of amikacin and cephalothin is related to decreased renal function and an increased V d .