I have Post-herpetic neurolgia due to a severe bout of shingles and am now into my 7th week. The last few weeks have been pure agony. When I researched and found I could possibly get some relief from lidocaine, I spoke to a pharmacist at Walmart. My husband brought it home and I immediately, with his help, covered the whole sensitive area. Then I read the pamphlet enclosed and it does not have any info regarding this type of use. Please advise if I should continue, and if so, how often can I apply? I am desperate!