Flupirtine (hydrochloride)

Flupirtine hydrochloride (D 9998 hydrochloride) is a selective neuropotassium channel opener with analgesic activity. Flupirtine hydrochloride is used to inhibit a variety of pain conditions, including chronic musculoskeletal pain, migraines, and neuralgia. Flupirtine hydrochloride has antidepressant and antioxidant properties and may increase the analgesic effect in combination therapy with morphine. Flupirtine hydrochloride relieves abnormally increased muscle tension and has a muscle relaxant effect. Flupirtine hydrochloride is clinically superior to other drugs, such as tramadol and pantoxan, plus its side effects are better tolerated. Flupirtine hydrochloride has a significant effect on inhibiting neural hyperexcitability and therefore exhibits inhibitory potential in various pain states[1].

[1]Kornhuber J, et al. Flupirtine shows functional NMDA receptor antagonism by enhancing Mg2+ block via activation of voltageindependent potassium channels. Rapid communication. J Neural Transm. 1999;106(9-10):857-67.|[2]Klinger F, et al. Concomitant facilitation of GABAA receptors and KV7 channels by the non-opioid analgesic flupirtine. Br J Pharmacol. 2012 Jul;166(5):1631-42.|[3]Swedberg MD, et al. Pharmacological mechanisms of action of flupirtine: a novel, centrally acting, nonopioid analgesic evaluated by its discriminative effects in the rat. J Pharmacol Exp Ther. 1988 Sep;246(3):1067-74.|[4]Wu SN, et al. Evidence for inhibitory effects of flupirtine, a centrally acting analgesic, on delayed rectifier k(+) currents in motor neuron-like cells. Evid Based Complement Alternat Med. 2012;2012:148403.|[5]Kolosov A, et al. Flupirtine enhances the anti-hyperalgesic effects of morphine in a rat model of prostate bone metastasis. Pain Med. 2012 Nov;13(11):1444-56.|[6]Michel MC, et al. Unexpected frequent hepatotoxicity of a prescription drug, flupirtine, marketed for about 30 years. Br J Clin Pharmacol. 2012 May;73(5):821-5.|[7]Flupirtine in pain management: pharmacological properties and clinical use