難治性うつ病に対する選択的セロトニン再取り込み阻害薬へのリスペリドン追加療法

Abstract

三環系抗うつ薬,四環系抗うつ薬による治療に反応が見られず,選択的セロトニン再取込み阻害薬(SSRI)であるフルボキサミンの単剤投与にも反応が見られなかったが,フルボキサミンに非定型抗精神病薬であるリスペリドンを追加したことにより著明に改善した難治性うつ病患者2例を経験した.リスペリドンの有する5-HT_<2A>受容体遮断作用が5-HT_<1A>受容体を介する神経伝達を増強し,その結果,不安,抑うつが軽減されることが示唆された.我々の症例では不安だけでなく制止症状も改善し,その改善が2週間以内という早期に現れた.また定型抗精神病薬で多く見られる錐体外路症状も認められなかった.難治性うつ病に対し,SSRIへのリスペリドン追加療法は新たな有効な治療手段であることが示唆された.Up to 30% of patients with major depression fail to respond to conventional treatment. Such refractory depression is a significant public health concern. We report the treatment course of two patients with refractory depression. Both had in common a long-term course of illness, episodes of major depression, and inadequate clinical response to various antidepressants. However, they responded soon after addition of a low dose of risperidone to a selective serotonin reuptake inhibitor (SSRI), fluvoxamine. Low-dose risperidone is much more potent in antagonizing the 5-HT_<2A> receptor than the D_2 receptor. Antagonism of 5-HT_<2A> may facilitate the action of serotonin at the 5-HT_<1A> receptor, leading to a decrease in depression and anxiety. The clinical responses in these patients were evident by the second week, suggesting a rapid onset of action. During the observation period, the absence of extrapyramidal symptoms was encouraging. Combined fluvoxamine and risperidone appears to be an effective and well tolerated treatment for refractory depression