Pharmacokinetics of Cephradine Administered Intravenously and Orally to Young and Elderly Subjects
| Autor: | Elizabeth A. Gill, Carl W. Norden, Terry L. Schwinghammer |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
Adult
Male Time Factors Metabolic Clearance Rate medicine.drug_class Antibiotics Administration Oral Biological Availability Renal function Urine Pharmacokinetics Oral administration medicine Humans Pharmacology (medical) Infusions Intravenous Cephradine Aged Aged 80 and over Pharmacology Volume of distribution business.industry Age Factors Bioavailability Anesthesia Female business Half-Life |
| Zdroj: | The Journal of Clinical Pharmacology. 30:893-899 |
| ISSN: | 0091-2700 |
| DOI: | 10.1002/j.1552-4604.1990.tb03568.x |
| Popis: | The pharmacokinetics of IV and oral cephradine in healthy young male and female volunteers (ages 19 to 25, n = 10) were compared to those of older individuals (ages 65 to 81, n = 9). Subjects received 1 gram of cephradine by a 5-minute intravenous (IV) infusion followed the next day by a 1-gram oral dose. Serial serum and urine samples collected over a period of 12 hours after the dose were analyzed for cephradine concentration by a microbiologic assay. After IV administration, mean serum cephradine concentrations in the elderly group were significantly higher at both 6 hours (1.52 +/- 0.41 mcg/mL) and 8 hours (0.73 +/- 0.22 mcg/mL) than in the young group at 6 hours (0.43 +/- 0.11 mcg/mL). Total systemic clearance was significantly lower (2.64 +/- 0.34 vs. 4.81 +/- 0.59 ml/min/kg) and the elimination half-life was significantly longer (1.71 +/- 0.20 vs 1.12 +/- 0.13 hours) in the elderly group (P = .0001). Systemic cephradine clearance correlated positively with creatinine clearance (r2 = 0.34, P = .0110) and negatively with age (r2 = 0.79, P = .0052). The mean volume of distribution was not significantly different between the two groups. Mean renal clearance was significantly lower in the elderly group (P = .0001), but more than 80% of the dose was excreted in the urine within 6 hours in both groups. After oral administration, the mean peak concentration and time to peak concentration did not differ between groups. The relative oral bioavailability was approximately 94% in both groups. The mean serum concentrations in the elderly were higher at both 6 and 8 hours than in the young group at 6 hours. There were no differences in pharmacokinetic parameters between male and female subjects. Because of reduced cephradine clearance secondary to an age-related decline in renal function, administration of cephradine every 8 hours, rather than every 6 hours, may be sufficient in elderly patients. |
| Databáze: | OpenAIRE |
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