Hashiguchi M, Fujimura A, Ohashi K, Ebihara A
Department of Clinical Pharmacology, Medical School of Oita, Japan.
J Clin Pharmacol. 1992 Feb;32(2):184-7. doi: 10.1002/j.1552-4604.1992.tb03824.x.
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 trial 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.
采用交叉设计，于上午10:00（日间试验）或晚上10:00（夜间试验）给9名健康受试者口服300毫克咖啡因。在给予咖啡因后的0.5、1、1.5、2、3、4、6和8小时采集唾液。在咖啡因给药后8小时收集尿液。日间试验期间唾液中的咖啡因清除率与夜间试验无差异。两项试验之间代谢物的尿摩尔比（AFMU + 1X + 1U/17U）未观察到显著差异。这些数据表明，唾液中的咖啡因清除率不随给药时间而变化。由于血浆中的咖啡因清除率反映在咖啡因代谢物的尿比值中，其在血浆中的清除率可能也不会因给药时间而改变。
