Patent ID: 8741332

Claim:
A formulation for treating neuropathic pain, comprising: a) at least one drug selected from the group consisting of ropivacaine, acyclovir, valacyclovir, pencyclovir, lidocaine, tetracaine, amitriptyline, ketamine, and combinations thereof; b) a solvent vehicle, comprising: i) a volatile solvent system including at least one volatile solvent, wherein volatile solvent system comprises about 10 wt % to about 85 wt % of the formulation, and ii) a non-volatile solvent system including at least one non-volatile solvent, wherein the non-volatile solvent system is flux-enabling for the drug and facilitates transdermal delivery of the drug at a therapeutically effective rate over a sustained period of time; and c) a peel-forming agent, wherein the formulation has a viscosity suitable for application and adhesion to a skin surface prior to evaporation of the volatile solvent system, wherein the formulation applied to the skin surface forms a solidified layer after at least partial evaporation of the volatile solvent system within about 15 minutes of application to the skin surface under standard skin and ambient conditions, and wherein the drug continues to be dermally delivered at the therapeutically effective rate after the volatile solvent system is evaporated.