Department of Clinical Psychology, University of Amsterdam, Amsterdam, The Netherlands.
Psychother Psychosom. 2012;81(1):29-37. doi: 10.1159/000329454. Epub 2011 Nov 22.
Research suggests that yohimbine hydrochloride (YOH), a noradrenaline agonist, can facilitate fear extinction. It is thought that the mechanism of enhanced emotional memory is stimulated through elevated noradrenaline levels. This randomized placebo-controlled trial examined the potential exposure-enhancing effects of YOH in a clinical sample of participants meeting DSM-IV criteria for a specific phobia (fear of flying).
Sixty-seven participants with fear of flying were randomized to 4 sessions of virtual reality exposure therapy (VRET) combined with YOH (10 mg), or 4 sessions of VRET combined with a placebo. Treatment consisted of 4 weekly 1-hour exposure sessions consisting of two 25-minute virtual flights. At pre- and post- treatment, fear of flying was assessed. The YOH or placebo capsules were administered 1 h prior to exposures. The manipulation of the noradrenaline activity was confirmed by salivary α-amylase (sAA) samples taken pre-, during and post-exposure.
Forty-eight participants completed treatment. Manipulation of noradrenaline levels with YOH was successful, with significantly higher levels of sAA in the YOH group when entering exposure. Results showed that both groups improved significantly from pre- to post-treatment with respect to anxiety reduction. However, although the manipulation of noradrenaline activity was successful, there was no evidence that YOH enhanced outcome.
Participants improved significantly on anxiety measures independently of drug condition, after 4 sessions of VRET. These data do not support the initial findings of exposure-enhancing effects of YOH in this dosage in clinical populations.
研究表明，盐酸育亨宾（YOH）是一种去甲肾上腺素激动剂，可促进恐惧的消退。人们认为，通过提高去甲肾上腺素水平来刺激增强情绪记忆的机制。这项随机安慰剂对照试验在符合 DSM-IV 特定恐惧症（飞行恐惧）标准的临床样本参与者中检查了 YOH 的潜在增强暴露效应。
67 名飞行恐惧参与者被随机分配到 4 个虚拟现实暴露治疗（VRET）联合 YOH（10mg）疗程，或 4 个 VRET 联合安慰剂疗程。治疗包括每周 1 小时的 4 次暴露，每次 25 分钟，进行两次虚拟飞行。在治疗前和治疗后评估飞行恐惧。YOH 或安慰剂胶囊在暴露前 1 小时给药。通过在暴露前、暴露中和暴露后采集唾液α-淀粉酶（sAA）样本来确认去甲肾上腺素活性的操纵。
48 名参与者完成了治疗。用 YOH 操纵去甲肾上腺素水平是成功的，YOH 组在进入暴露时 sAA 水平明显升高。结果表明，两组在治疗后焦虑程度都有显著改善。然而，尽管去甲肾上腺素活动的操纵是成功的，但没有证据表明 YOH 增强了结果。
参与者在接受 4 个疗程的 VRET 后，在焦虑测量方面有了显著的改善，与药物状况无关。这些数据不支持 YOH 在该剂量下对临床人群具有增强暴露效应的最初发现。
