目的：血清素症候群 (serotonin syndrome) 是因中樞神經系統的血清素含量過高所產生的藥物不良反應，儘管發生率不高，但嚴重時可能導致死亡。本文研究目的藉由系列案例研究及文獻回顧，探討和分析可能導致血清素症候群的血清素作用藥物(serotonergic drugs) 類型組合和症狀表現。
方法：回溯性收集某醫院藥物不良反應系統資料庫，自2008 年1 月1 日至2019年7 月31 日，通報血清素症候群的個案，並進行文獻回顧及討論。
結果：共收納6 個個案，其中4 名女性和2 名男性。平均年齡為56.2 歲，年齡範圍為15 ~ 79 歲。結果顯示，血清素抗憂鬱劑 (serotonergic antidepressants) 是這些血清素症候群個案最常見的用藥，6 個個案中有5 位使用選擇性血清素回收抑制劑 (selective serotonin reuptake inhibitor) 或血清素—正腎上腺素回收抑制劑 (serotoninnoradrenaline inhibitors)。這5 個個案有2 位併用第二代抗精神病藥物 (secondgeneration antipsychotic drugs, SGAs)、2 位併用opioids。常見的臨床症狀有精神狀態改變 (n = 5)、陣攣或肌陣攣 (n = 4) 和心搏過速 (n = 3)。有3 個個案出現高熱並伴隨肌酸激酶 (creatine kinase) 升高。有5 個個案使用cyproheptadine 治療或合併benzodiazepines 治療。所有的個案在治療後症狀皆改善。
結論：我們的研究與文獻顯示，因抗憂鬱藥、opioids 和SGAs 使用的增加，彼此間交互作用也隨之增加，導致血清素症候群發生風險提高。並提醒臨床上在開立血清素作用藥物 (serotonergic agents) 或同時使用多種同類藥物時，應瞭解病人的用藥史和警覺症狀變化，以避免血清素症候群的發生。

Objective: Serotonin syndrome is a spectrum of adverse effects caused by excessive central nervous system levels of serotonin. It is relatively rare but potentially lifethreatening. This study aimed to investigate the association of serotonergic drugs and clinical symptoms in patients with serotonin syndrome by case series and literature review.
Methods: We retrospectively reviewed the medical records of serotonin syndrome cases reported to the institutional adverse drug reaction reporting system from January 1, 2008 to July 31, 2019.
Results: Six cases of serotonin syndrome were reviewed (4 female and 2 male). The mean age was 56.2 years with a range of 15 to 79 years. Our results reveal that antidepressants were the most commonly involved serotonergic drugs, and 5 out of the 6 patients took either serotonin reuptake inhibitor or serotonin-noradrenaline. Of these 5 patients, 2 patients took second-generation antipsychotic drugs (SGAs) and 2 patients took opioids concurrently. The most common clinical presentations were altered mental status (n = 5), clonus or myoclonus (n = 4), and tachycardia (n = 3). Three patients presented with hyperthermia and complicated with the elevation of creatine kinase. Five patients were treated with cyproheptadine (with/without benzodiazepines). All of our patients recovered after treatment.
Conclusions: Our study and literature review show that the increased use of antidepressants, opioids, and SGAs, and interactions among these drugs, may lead to the occurrence of serotonin syndrome to increase. Therefore, clinicians should review medication history, be cautious when treating patients with multiple serotonergic agents, and be aware of the alarming change of symptoms to avoid the occurrence of serotonin syndrome.

Summited for publication: 2020.6.19; Accepted for publication: 2020.9.20