Objective: To observe the curative effect of Yiqi Huoxue Fang (YHF) combined with ketamine anesthesia in vertebral canal on treating intractable postherpetic neuralgia(PHN). Method: One hundred and ten cases of PHN were randomly divided into control group (n=54) and treatment group (n=56).All patients were given ketamine spinal block therapy once a week for a total of eight times.The treatment group on this basis was received YHF once daily(given by half dose

bid).The patients in two groups were given multi-analgesic tramadol when necessary during the investigation of 8 weeks. Result: After treatment for 7 days

4 weeks and 8 weeks

the Visual analogue scale(VAS) scores of the treatment group were lower than those in the control group(P<0.01); the efficacy in the treatment group was significantly better than the control group(P<0.01).The quality of life(QOL) scores in the treatment group after treatment of 4 weeks and 8 weeks were higher than those in the control group (P<0.01); and the consumed tramadol in the treatment group was (230.5±72.4)mg

which is lower than that in the control group (725.7±581.9)mg (P<0.01). Conclusion: YHF combined with ketamine spinal block is effective and safe in the treatment of intractable PHN.