Roth T, Roehrs T, Koshorek G, Sicklesteel J, Zorick F
J Allergy Clin Immunol. 1987 Jul;80(1):94-8. doi: 10.1016/s0091-6749(87)80197-5.
The central effects of a newly developed, long-acting H1 antihistamine, loratadine (10 and 40 mg), were compared with those of a standard H1 antihistamine, diphenhydramine (50 mg three times a day) with measures of performance and daytime sleepiness (multiple sleep latency test). Sixteen healthy adults (six women and 10 men), 19 to 35 years of age, received each of the drugs and placebo for 2 days, separated by 5 days at home. Each day, the drug or placebo was administered at 8 A.M. and 12 and 4 P.M. Diphenhydramine was administered in three equal doses (50 mg), and loratadine was administered in a single dose followed by two placebo doses. Mean latency to sleep on tests done at 9 and 11 A.M. and 1, 3, and 5 P.M. was reduced significantly with diphenhydramine compared to placebo, whereas neither loratadine dose reduced sleep latency. Performance measured at 9:30 P.M. and 1:30 P.M. with a battery of tests, including reaction time, vigilance, digit symbol substitution, and symbol copying tasks demonstrated a significant reduction in symbols copied and digits substituted after diphenhydramine compared to both loratadine doses. These results demonstrate that loratadine (10 and 40 mg doses) did not have clinically significant central nervous system activity, whereas diphenhydramine increases sleepiness and disrupts performance efficiency.
将一种新研发的长效H1抗组胺药氯雷他定（10毫克和40毫克）的中枢效应，与一种标准H1抗组胺药苯海拉明（每日三次，每次50毫克）的中枢效应进行比较，采用了性能和日间嗜睡测量方法（多次睡眠潜伏期试验）。16名年龄在19至35岁之间的健康成年人（6名女性和10名男性），每种药物和安慰剂各服用2天，中间在家休息5天。每天上午8点、中午12点和下午4点服用药物或安慰剂。苯海拉明分三次等量服用（50毫克），氯雷他定单次服用，随后服用两次安慰剂。与安慰剂相比，上午9点和11点以及下午1点、3点和5点进行的测试中，苯海拉明显著缩短了入睡平均潜伏期，而氯雷他定的两种剂量均未缩短睡眠潜伏期。晚上9点30分和下午1点30分进行的一系列测试，包括反应时间、警觉性、数字符号替换和符号抄写任务，结果显示，与氯雷他定的两种剂量相比，苯海拉明服用后抄写的符号和替换的数字显著减少。这些结果表明，氯雷他定（10毫克和40毫克剂量）没有临床上显著的中枢神经系统活性，而苯海拉明会增加嗜睡并干扰执行效率。
