Transcutaneous electrical nerve stimulation (TENS) is a floor-used unit that provides very low voltage electrical existing through the skin to create analgesia. Corydalis would be the genus of the perennial flowering plant from the poppy family with about 400 species. The tubers of corydalis (corydalis yanhusuo yan hu suo; https://andreygklm.ampedpages.com/the-ultimate-guide-to-alternative-natural-pain-relief-to-replace-traditional-painkillers-65615952