a heating acupuncture needle , comprising a source of external energy which heats a heating structure , the heating structure extending over at least most of the length of the needle and comprising an electrically conductive envelope surrounding the needle but leaving an upper end of the needle uncovered . the needle has a tip which is uncovered by the electrically conductive envelope , or which in another embodiment is uncovered . there is an electrically insulating layer between the electrically conductive envelope and the needle , which may surround the tip of the needle or may expose the tip of the needle .