Paroxetine投与中に出血時間延長および血小板数減少を伴わない紫斑が出現したパニック障害の1例について

Spontaneous Ecchymoses Developed on a Patient under Medication of Paroxetine for Panic Disorder, Even though Her Platelet Count and Bleeding Time were Normal

抄録

　Paroxetine30mg/日を投与中に，出血時間延長も血小板数減少もなく紫斑が出現し，投薬減量で紫斑は軽快したものの退薬症候群を合併したパニック障害の30歳女性の1例を報告する。選択的セロトニン再取り込み阻害薬(SSRI)による出血性の副作用報告を海外で散見し，特にparoxetineでは出血時間延長や血小板減少を伴わない出血例も報告されている。本例を含めて複数の報告において患者は同症状をすぐには副作用として認識できておらず，SSRIの開始前には出血性副作用の説明を要する。またSSRIでは退薬症候群が発現しやすいため副作用発現時の減薬にも工夫を要する。同症状の発生機序としては，ADPに誘導された血小板凝集のSSRIによる阻害の報告との関係，また血管脆弱性との関係が推測される。

Summary

　A 30-year-old woman diagnosed as panic disorder and who was under medication of paroxetine 30mg/day developed ecchymoses on her four extremities, but the investigations showed that her platelet-count and bleeding time were normal. By decreasing the dose of paroxetine her ecchymoses gradually diminished, but withdrawal symptoms, headache and hypersensitivity developed, which made it difficult to deal with the bleeding event. This is the first Japanese case report of bleeding with normal platelet count and normal bleeding time under medication of paroxetine. The patient had not noticed the event was due to paroxetine and continued to take it as had other patients described in some of the reports on this phenomenon. Practitioners should give an explanation of the bleeding side-effect of this selective serotonin reuptake inhibitor (SSRI) to patients for whom they prescribe paroxetine. Withdrawal symptoms of SSRI make it difficult to deal with the bleeding. The process of the bleeding events caused by SSRIs may be related to the fact that they inhibit ADP-induced platelet aggregation, and/or to capillary fragility.