Hello dear, Welcome to healthcaremagic. I have read your query and understood your concern. Postherpetic neuralgia is really a bothersome condition usually found in old aged people. Various drugs are available for the pain relief and treatment of this condition like combination of methylcobalamin with gabapentin/ pregabalin, amitriptyline etc. Topical medications like lignocaine , capsacin also provide relief to some extent. You may discuss it with your doctor. I hope he/she will agree with my opinion. If you have further query, you may ask me. Stay healthy.