The dose-effect relationship of electroacupuncture analgesia and its stimulus parameters: Progress in the last 3 decades

In this review, we explored the dose-effect relationship of electroacupuncture (EA) analgesia and its stimulus parameters by searching articles on clinical and experimental research of EA analgesia in the past 30 years. The impacts on the analgesic effects are discussed in terms of the pulse waveform, frequency, amplitude, wave width, and time effect, as well as parameter combinations, and the optimization of the EA parameters are summarized for the treatment of neuropathic, inflammatory, and cancer pains. It was initially discovered that the distant-dense (D-D) wave (2/15 Hz or 2/100 Hz) and stimulus for 30 -45 min were appropriate in the treatment of chronic inflammatory pain, the strong stimulus was applicable to the acute stage of pain (twice a week), while the weak stimulus was for the stable stage (once weekly). The continuous (2 Hz)/D-D wave (2/100 Hz) and moderate/low intensity of stimulus for 30 -45 min are preferred in the treatment of neuropathic pain with EA, once daily or every 2 days. Regarding the treatment of cancer pain, EA with continuous (2 Hz or 100 Hz) or D-D wave (2/100 Hz), moderate and low intensity of stimulus for 30 -45 min is adopted, once every 2 days. There is a certain rule for the correlation of each parameter and the combination of parameters to ensure an analgesic effect of EA, which should be further explored in future studies. & COPY; 2022 Published by Elsevier B.V. on behalf of World Journal of Acupuncture Moxibustion House.