The current topical medication for postherpetic neuralgia is lidocaine patch, which is currently the first line of medication for postherpetic neuralgia, and patients are advised to use the medication under the supervision of a doctor. The principle of action of lidocaine patch is to improve the postherpetic neuralgia through the action of local anesthesia of lidocaine; it is usually used on unbroken skin, covering the area with the most severe pain. It is contraindicated in patients with a history of hypersensitivity to amide-based local anesthetics or to other components of the product. If improvement is not apparent with topical agents alone, oral calcium channel modulators such as pregabalin or gabapentin may be used in combination. For patients with postherpetic neuralgia, it is recommended to go to a regular hospital for timely examination and treatment with medication under the guidance of a professional doctor.