Int J Clin Pharmacol Ther. 2022 Apr;60(4):184-187. doi: 10.5414/CP204068.
Trazodone is prescribed off-label to treat insomnia, especially in older, not depressed adults. At low doses, it blocks histamine-1 (H1) receptors having a hypnotic effect. Unusual but potentially severe side effects of trazodone include suicidal behavior, excess sedation, QT prolongation, and priapism. Three case studies have been published in the last four decades describing trazodone-induced parkinsonism.
A 78-year-old Caucasian male with a past medical history of paroxysmal atrial fibrillation (on amiodarone), major depressive disorder, chronic obstructive pulmonary disease, hypothyroidism, and obstructive sleep apnea, was prescribed trazodone for his chronic insomnia. After 1 month, he was seen in the emergency department (ED) with complaints of coarse tremors of his upper extremities and could not write with a pen anymore due to shaking. He noticed dragging of his feet while walking for over a month, which caused him to have multiple falls and significantly impacted his activities of daily living. On clinical exam, the patient had bilateral cogwheel rigidity in ankles and shuffling gait. Trazodone was discontinued, and his symptoms resolved within a week.
Trazodone was likely causing parkinsonism in our patient. Amiodarone may have hindered trazodone metabolism causing higher levels in blood. Multiple mechanisms of trazodone's effect on dopamine have been suggested, but the serotonin-dopamine system interaction remains significant. Physicians need to contemplate the benefits and detriments before adding more medications to the list for older adults. Polypharmacy can amplify the adverse effects of a drug that might not be seen in everyday practice.
曲唑酮被开出处方用于治疗失眠，尤其适用于年龄较大但无抑郁的成年人。低剂量时，它会阻断组胺-1（H1）受体，从而产生催眠作用。曲唑酮的一些不常见但可能很严重的副作用包括自杀行为、过度镇静、QT 间期延长和阴茎异常勃起。在过去四十年中，已有三篇病例研究报告了曲唑酮引起的帕金森病。
一名 78 岁白人男性，既往有阵发性心房颤动（服用胺碘酮）、重度抑郁症、慢性阻塞性肺疾病、甲状腺功能减退症和阻塞性睡眠呼吸暂停病史，因慢性失眠而被开处曲唑酮。一个月后，他因上肢粗震颤和无法用钢笔写字而到急诊科就诊。他注意到脚拖地，这种情况已经持续了一个多月，导致他多次跌倒，严重影响了日常生活活动。临床检查发现，患者踝关节有双侧齿轮样僵硬，步态拖曳。停用曲唑酮后，他的症状在一周内得到缓解。
曲唑酮可能导致了我们患者的帕金森病。胺碘酮可能会阻碍曲唑酮的代谢，导致血液中的水平升高。已经提出了曲唑酮对多巴胺作用的多种机制，但 5-羟色胺-多巴胺系统的相互作用仍然很重要。医生在为老年人添加更多药物之前，需要权衡利弊。药物的不良反应可能会因药物相互作用而放大，这种情况在日常实践中可能不会被发现。
