The effect of vitamin C on the pharmacokinetics of caffeine in elderly men.
Am J Clin Nutr
; 35(3): 487-94, 1982 Mar.
Article
en En
| MEDLINE
| ID: mdl-7064899
ABSTRACT
The influence of vitamin C on the pharmacokinetics of caffeine was investigated in 10 elderly males, age 66 to 86 yr. Caffeine was administered intravenously on three different occasions over a 7-wk period before vitamin C restriction, after approximately 4 wk of vitamin C restriction (15 mg dietary intake per day), and after 2 wk of vitamin C supplementation (500 mg orally, twice daily). Blood and urine samples were collected over a 48-h period after each caffeine administration. The plasma half-life, rate constant of elimination, apparent volume of distribution, total body clearance, renal clearance, and metabolic clearance of caffeine were determined. Simultaneous plasma, whole blood and leukocyte vitamin C concentrations were obtained. All of the average vitamin C concentrations monitored (plasma, whole blood, and leukocyte) changed significantly during the study, corresponding to the alterations in dietary vitamin C intake. Conversely, none of the caffeine pharmacokinetic parameters evaluated changed significantly during the study. The average metabolic clearance was approximately 77 (ml hr-1) kg-1 and the average half-life was approximately 4.6 h for all caffeine administrations. These results indicate that the elimination of caffeine in the elderly is not affected significantly by the concentrations of vitamin C achieved during this study.
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Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Ácido Ascórbico
/
Anciano
/
Cafeína
Límite:
Humans
/
Male
Idioma:
En
Revista:
Am J Clin Nutr
Año:
1982
Tipo del documento:
Article