Background Ketamine appears to have a therapeutic role in certain mental disorders, most notably unipolar major depressive disorder. However, its efficacy in bipolar depression is less clear. This study aimed to assess the efficacy and tolerability of ketamine for bipolar depression. Methods We conducted a systematic review of experimental studies using ketamine for the treatment of bipolar depression. We searched PubMed, MEDLINE, Embase, PsycINFO, and the Cochrane Central Register for relevant studies published since each database’s inception. We synthesized evidence regarding efficacy (improvement in depression rating scores) and tolerability (adverse events, dissociation, dropouts) across studies. Results We identified 6 studies, with 135 participants (53% female; 44.7 years; standard deviation, 11.7 years). All studies used 0.5 mg/kg of add-on intravenous racemic ketamine, with the number of doses ranging from 1 to 6; all participants continued a mood-stabilizing agent. The overall proportion achieving a response (defined as those having a reduction in their baseline depression severity of at least 50%) was 61% for those receiving ketamine and 5% for those receiving a placebo. The overall response rates varied from 52% to 80% across studies. Ketamine was reasonably well tolerated; however, 2 participants (1 receiving ketamine and 1 receiving placebo) developed manic symptoms. Some participants developed significant dissociative symptoms at the 40-minute mark following ketamine infusion in 2 trials. Conclusions There is some preliminary evidence supporting use of intravenous racemic ketamine to treat adults with bipolar depression. There is a need for additional studies exploring longer-term outcomes and alterative formulations of ketamine.

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双相抑郁症的氯胺酮：系统评价

背景 氯胺酮似乎在某些精神障碍中具有治疗作用，尤其是单相重度抑郁症。然而，其在双相抑郁症中的疗效尚不清楚。本研究旨在评估氯胺酮治疗双相抑郁症的疗效和耐受性。方法 我们对使用氯胺酮治疗双相抑郁症的实验研究进行了系统评价。我们搜索了 PubMed、MEDLINE、Embase、PsycINFO 和 Cochrane Central Register，以查找自每个数据库成立以来发表的相关研究。我们综合了研究中关于疗效（抑郁评分的提高）和耐受性（不良事件、分离、辍学）的证据。结果 我们确定了 6 项研究，有 135 名参与者（53% 为女性；44.7 岁；标准差，11.7 岁）。所有研究均使用 0。5 mg/kg 外消旋氯胺酮静脉滴注，给药次数为 1 至 6 次；所有参与者都继续使用情绪稳定剂。接受氯胺酮的患者获得缓解（定义为基线抑郁严重程度降低至少 50%）的总体比例为 61%，接受安慰剂的患者为 5%。整个研究的总体反应率从 52% 到 80% 不等。氯胺酮的耐受性相当好；然而，2 名参与者（1 名服用氯胺酮，1 名服用安慰剂）出现躁狂症状。在 2 项试验中，一些参与者在输注氯胺酮后 40 分钟出现明显的解离症状。结论 有一些初步证据支持使用静脉内消旋氯胺酮治疗成人双相抑郁症。