從安非他命濫用到愷他命濫用

A Roller Coaster from Methamphetamine to Ketamine

臺灣過去十多年來在藥物濫用盛行率方面，似有由甲基安非他命(methamphetamine)轉為愷也命(ketamine)的趨勢。臺灣的學者們有關於甲基安非他命依賴及其引發精神病之研究成果，不論是臨床特徵方面或是誘發基因之相關性調查，在相關研究領域中皆有重要的貢獻與影響。安非他命多巴胺系統的作用以及愷他命對glutamate系統的作用，在過去人體與動物研究中分別模擬了精神分裂症（思覺失調症）在正性與負性症狀的不同面向，讓學者們對精神疾病機轉上有深一的了解，從而也影響了治療。本篇文章的第一部分，我們將針對甲基安非他命濫用與甲基安非他命精神病的進行文獻探討，特別是著重在臺灣進的研究。而在第二部分，我們討論愷他命的生理機多及對人體之作用，特別是長期濫用後之各類副作用，比如膀胱問題、腹部疼痛、神經認知損傷、憂鬱症、精神病、以及成癮問題。由於有關愷他命的神經適應作用以及迴饋機制仍尚未清楚，未來仍需要更多的研究，以精進我們在其臨床使用的益處以及濫用危害的了解。

A trend of drug abuse shifting from methamphetamine (METH) to ketamine in Taiwan has been witnessed in Taiwan in the past decade. The research in exam-ining the clinical characteristics and genetic predispositions of METH dependence and psychosis in Taiwan has had a great impact in the pertinent fields. The effects of amphetamine and ketamine have provoked interest in studying the rôle of dopa-mine theory and glutamatergic hypothesis in schizophrenia, both of which mimic different aspects of the illness. In the first part of this overview paper we review the studies on METH abuse and METH psychosis, particularly those conducted in Taiwan. And in the second part, we address the complex mechanisms of ketamine action and the adverse outcomes associated with chronic ketamine abuse such as cystitis, abdominal pain, neurocognitive impairment, depression, and psychosis. Because the neuroadaptation and reward related to ketamine are not entirely clear, future studies are needed to advance our understanding both its clinical uses and abuse.