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Diurnal Effect on Caffeine Clearance
Author(s) -
Hashiguchi Masayuki,
Fujimura Akio,
Ohashi Kyoichi,
Ebihara Akio
Publication year - 1992
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.1552-4604.1992.tb03824.x
Subject(s) - caffeine , saliva , crossover study , dosing , urine , oral administration , urinary system , medicine , chemistry , pharmacology , placebo , alternative medicine , pathology
Caffeine (300 mg) was given orally to nine healthy subjects at 10:00 am (day trial) or at 10:00 pm (night trial) using a crossover design. Saliva was obtained at 0.5, 1, 1.5, 2, 3, 4, 6, and 8 hours after administration of caffeine. Urine was collected for 8 hours after caffeine dosing. Caffeine clearances in saliva during the day tried were not different from those in the night trial. No significant difference was observed in urinary molar ratios of metabolites (AFMU+ 1X + 1U / 17U) between the two trials. These data suggest that caffeine clearances in saliva do not vary with its administration time. Since caffeine clearances in plasma are reflected in the urinary ratios of caffeine metabolites, its clearance in plasma might also not be altered by the time of dosing.