Flupirtine HCl is the salt form of Flupirtine, also known as W-2964, an aminopyridine that functions as a centrally acting non-opioid analgesic. It first became available in Europe in 1984, and is sold mainly under the names Katadolon, Trancolong, Awegal, Efiret, Trancopal Dolo, and Metanor. Like nefopam, it is unique among analgesics in that it is a non-opioid, non-NSAID, non-steroidal centrally acting analgesic. Flupirtine is a selective neuronal potassium channel opener that also has NMDA receptor antagonist and GABAA receptor modulatory properties.