[Pharmacological effects of nalfurafine hydrochloride, a kappa-opioid receptor agonist].

Nalfurafine hydrochloride, a kappa-opioid receptor agonist, was approved in January 2009 and released to the market on March 2009 for the indication of "Improvement of pruritus in hemodialysis patients (only for cases resistant to conventional treatments)" in Japan (Brand Name: REMITCH CAPSULES 2.5 microg, Marketing Authorization Holder: Toray Industries, Inc., Distributed by Torii Pharmaceutical Co., Ltd., Co-developed by Japan Tobacco Inc.). In addition to antipruritic effect, nalfurafine hydrochloride showed ameliorating effects on pain, neuropathic pain, drug dependence, schizophrenia and dyskinesia in non-clinical studies. Therefore, nalfurafine hydrochloride may become a useful therapeutic agent for their diseases.