Muether P S, Gwaltney J M
Aachen Medical School, Aachen, Germany.
Clin Infect Dis. 2001 Nov 1;33(9):1483-8. doi: 10.1086/322518. Epub 2001 Oct 4.
Treatment with first-generation antihistamines reduces sneezing, rhinorrhea, nasal mucus weight, and, in some instances, cough in subjects with experimental or natural colds; however, treatment with second-generation antihistamines has not been effective for these complaints in trials in subjects with natural colds. This article reports the negative results of a clinical trial with loratadine, a second-generation antihistamine, in adults in the rhinovirus challenge model. This finding in the highly controlled setting of the challenge model confirms the earlier negative studies with second-generation antihistamines in natural colds. First-generation antihistamines block both histaminic and muscarinic receptors as well as passing the blood-brain barrier. Second-generation antihistamines mainly block histaminic receptors and do not pass the blood-brain barrier. The effectiveness of first-generation antihistamines in blocking sneezing in colds may be due primarily to neuropharmacological manipulation of histaminic and muscarinic receptors in the medulla.
第一代抗组胺药治疗可减轻实验性或自然感冒受试者的打喷嚏、流涕、鼻黏液重量，在某些情况下还可减轻咳嗽；然而，在自然感冒受试者的试验中，第二代抗组胺药治疗对这些症状并无效果。本文报道了在鼻病毒激发模型中，第二代抗组胺药氯雷他定在成人中的一项临床试验的阴性结果。在高度受控的激发模型中得到的这一发现证实了早期关于第二代抗组胺药治疗自然感冒的阴性研究。第一代抗组胺药可阻断组胺能和毒蕈碱能受体，并能透过血脑屏障。第二代抗组胺药主要阻断组胺能受体，不能透过血脑屏障。第一代抗组胺药在感冒时阻断打喷嚏的有效性可能主要归因于对延髓中组胺能和毒蕈碱能受体的神经药理学调控。
