Abstract：
Sleep laboratory and outpatient studies of the hypnotic efficacy of the amino acid L-tryptophan are reviewed, with particular emphasis on evaluation of therapeutic effectiveness in the treatment of insomnia. In younger situational insomniacs, whose sleep problem consists solely of longer than usual sleep latencies, L-tryptophan is effective in reducing sleep onset time on the first night of administration in doses ranging from 1 to 15 g. In more chronic, well-established sleep-onset insomnia or in more severe insomnias characterized by both sleep onset and sleep maintenance problems, repeated administration of low doses of L-tryptophan over time may be required for therapeutic improvement. In these patients, hypnotic effects appear late in the treatment period or, as shown in some studies, even after discontinuation of treatment. The improvement in sleep measures post-treatment has given rise to use of a treatment regimen known as \"interval therapy\", in which L-tryptophan treatment alternates with an L-tryptophan-free interval until improvement occurs. The absence of side effects and lack of development of tolerance in long-term use are important factors in the decision to embark upon a trial of L-tryptophan treatment. In addition, L-tryptophan administration is not associated with impairment of visuomotor, cognitive, or memory performance, nor does it elevate threshold for arousal from sleep.
摘要：
综述了氨基酸L-色氨酸催眠功效的睡眠实验室和门诊研究，特别强调评估治疗失眠的疗效。在年轻的情境失眠症患者中，其睡眠问题仅由比通常更长的睡眠延迟组成，L-色氨酸在1至15g的剂量范围内有效减少给药第一晚的睡眠开始时间。在更慢性的情况下，公认的睡眠发作性失眠或以睡眠发作和睡眠维持问题为特征的更严重的失眠，随着时间的推移,可能需要反复施用低剂量的L-色氨酸以改善治疗效果.在这些患者中,催眠作用出现在治疗后期或，如一些研究所示，即使在停止治疗后。治疗后睡眠措施的改善导致使用称为“间隔治疗”的治疗方案，其中L-色氨酸治疗与无L-色氨酸间隔交替，直到出现改善。长期使用中没有副作用和缺乏耐受性是决定开始进行L-色氨酸治疗试验的重要因素。此外,L-色氨酸给药与视觉运动损伤无关，认知，或内存性能，它也不会提高睡眠唤醒的阈值。
