Even though anticonvulsants and antidepressants can treat neuropathic pain, about half of those who take them will not see any improvement [source: Moore, Wiffin, Derry and McQuay]. In these cases, topical pain relievers might help.
Lidocaine is one that has been around since the 1940s. It's so well-known as an analgesic that Meredith Grey, the protagonist of the popular television show "Grey's Anatomy," is quoted as saying, "I'm having a miscarriage. I need Lidocaine." in the nail-biting season six finale [source: Grey's Anatomy]. Lidocaine works on neuropathic pain by blocking voltage-gated sodium channels. Typically, it's prescribed in 5 percent patches. Up to three patches can be applied topically on a localized painful area and worn for 24 hours.
Capsaicin poses an alternative topical treatment. The active ingredient in capsaicin is derived from chili peppers, and capsaicin patches and creams are widely available over the counter for the deep-heating treatment of minor muscle pain. The dosages required for the treatment of chronic neuropathic pain, however, are much higher and require a prescription. In one study, patients applied a single high-dose (8 percent) capsaicin patch. Thirty-three percent of patients reported a 50 percent reduction in pain. Fifty percent reported at least a 30 percent reduction. The positive effects of the patch lasted around 12 weeks [source: Gever].
For cases where topical treatments don't provide enough relief or where neuropathic pain is random or not localized, patients may want to try something a little crazier than a cream.