Flupirtine, a re-discovered drug, revisited

Abstract

Flupirtine was developed long before KV7 (KCNQ) channels were known. However, it was clear from the beginning that flupirtine is neither an opioid nor a nonsteroidal anti-inflammatory analgesic. Its unique muscle relaxing activity was discovered by serendipity. In the meantime, broad and intensive research has resulted in a partial clarification of its mode of action. Flupirtine is the first therapeutically used KV7 channel activator with additional GABAAergic mechanisms and thus the first representative of a novel class of analgesics. The presently accepted main mode of its action, potassium KV7 (KCNQ) channel activation, opens a series of further therapeutic possibilities. One of them has now been realized: its back-up compound, the bioisostere retigabine, has been approved for the treatment of epilepsy. © 2013 Springer Basel.