Markoula Sofia, Konitsiotis Spyridon, Chatzistefanidis Dimitrios, Lagos Georgios, Kyritsis Athanassios P
Department of Neurology, University of Ioannina, Ioannina, Greece.
Clin Neuropharmacol. 2010 Jan-Feb;33(1):50-1. doi: 10.1097/WNF.0b013e3181bf213b.
Mirtazapine is an antidepressant blocking presynaptic alpha2-adrenergic receptors and an antagonist of 5-hydroxytryptamine 2A/2C, 5-hydroxytryptamine 3, and histaminergic (H) postsynaptic receptor. Acute dystonia restless legs syndrome (RLS) and manic syndromes are adverse effects of mirtazapine, whereas only few cases of acute akathisia, after the first doses of mirtazapine, are referred. Instead, mirtazapine is used to treat akathisia probably because of its antagonistic property at H1 postsynaptic receptors and dopaminergic action in the frontal cortex.
A 72-year-old woman with depression, on mirtazapine treatment for almost 20 years, was admitted to an outpatient neurology clinic, with 1-week history of 3-kg weight loss and progressive intense "inner restlessness," constant movements of the legs and feet, remarkable distress, insomnia, and pacing up and down. Neurological examination had normal results, no deterioration of the depression was present, a magnetic resonance scan of the brain was unremarkable, and biochemical tests were within reference ranges. The disorder eventually resolved after the permanent withdrawal of the offending medication.
After excluding other possible disorders, the diagnosis of severe akathisia, possibly induced by mirtazapine, was made. The reappearance of the symptoms after the patient had been rechallenged with mirtazapine ascertained the diagnosis of akathisia induced by mirtazapine. This report relates akathisia with mirtazapine intake after such a long period of treatment. It illustrates the importance of being alert to any movement disorder emerging in patients treated with mirtazapine, even after many years of treatment.
米氮平是一种抗抑郁药，可阻断突触前α2-肾上腺素能受体，也是5-羟色胺2A/2C、5-羟色胺3和组胺能（H）突触后受体的拮抗剂。急性肌张力障碍、不宁腿综合征（RLS）和躁狂综合征是米氮平的不良反应，而仅有少数关于首次服用米氮平后出现急性静坐不能的病例报道。相反，米氮平被用于治疗静坐不能，可能是因为其对H1突触后受体的拮抗特性以及在额叶皮质的多巴胺能作用。
一名72岁患有抑郁症的女性，服用米氮平治疗近20年，因1周内体重减轻3千克、进行性强烈的“内心不安”、下肢和足部持续运动、明显痛苦、失眠以及来回踱步而入住门诊神经科诊所。神经系统检查结果正常，抑郁症无恶化，脑部磁共振扫描无异常，生化检查在参考范围内。在停用致病药物后，该病症最终得以缓解。
在排除其他可能的病症后，诊断为可能由米氮平诱发的严重静坐不能。患者再次服用米氮平后症状复发，确定了米氮平诱发静坐不能的诊断。本报告阐述了在如此长时间治疗后静坐不能与米氮平摄入之间的关系。它说明了对于接受米氮平治疗的患者，即使经过多年治疗，对出现的任何运动障碍保持警惕的重要性。
