Postherpetic neuralgia (PHN) is a severe condition that remains a challenge to treat. Spinal cord stimulation (SCS) is used in cases of insufficient efficacy of conservative treatment.

Spinal cord stimulation is an established treatment option for patients with pharmacologically resistant PHN. High-frequency stimulation, burst stimulation, and dorsal root ganglion stimulation are promising options in the management of PHN due to the absence of paresthesias which can be painful for patients with PHN. 

https://pubmed.ncbi.nlm.nih.gov/37007861/

Vitamin B12 for herpetic neuralgia: A meta-analysis of randomised controlled trials

Compared with the placebo group, the Vitamin B12 group exhibited a significant decrease in the Numeric Rating Scale score, with a mean difference of -4.01 (95% confidence interval = -4.70 to -3.33). Vitamin B12 administration improved the quality of life of PHN patients with moderate quality evidence and significantly decreased the number of patients using analgesics.