Efficacy and Safety of Lidocaine Infusion Treatment in Management of Neuropathic Pain

Inclusion Criteria: * postherpetic neuralgia, diabetic polyneuropathy, peripheral neuropathy * NRS score \> 4 * stable oral medication during the 1 month trial period * volunteers with informed consent Exclusion Criteria: * pregnancy, breastfeeding, possibility of pregnancy * pain from causes other than upper 3 indications * hypersensitivity to lidocaine or other local anesthetics * important disease of heart, kidney, liver or incurable disease that may affect the assessment of adverse effects, or may interfere with the completion of study * severe conduction block * history of other interventions that may affect the study * Enrollment in other clinical trials within 30 days * otherwise not suitable to study