Go-sha-jinki-Gan (GJG) ameliorates allodynia in chronic constriction injury model mice via suppression of TNF-α expression in the spinal cord

Background Alternative medicine is noted for its clinical effect and minimal invasiveness in the treatment of neuropathic pain. Go-sha-jinki-Gan, a traditional Japanese herbal medicine, has been used for meralgia and numbness in elderly patients. However, the exact mechanism of GJG is unclear. This study aimed to investigate the molecular mechanism of the analgesic effect of GJG in a chronic constriction injury model. Results GJG significantly reduced allodynia and hyperalgesia from the early phase (von Frey test, p