Past Issues

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.