An Investigation into the Hypoalgesic Effects of Transcutaneous Piezoelectric Current on Experimentally Induced Thermal Stimuli in Healthy Participants

Objectives: To investigate the effects of transcutaneous piezoelectric currents on experimentally induced thermal pain in healthy human participants. Materials and Methods: A repeated measure cross-over study recorded sensory detection and pain thresholds to contact thermal stimuli during active and placebo (no current) transcutaneous piezoelectric current in 15 pain-free healthy human volunteers. Active transcutaneous piezoelectric current (6 μA) was delivered as 35 high voltage single rectangular pulses (1 Hz) at the LI4 (Hegu) acupuncture point. Results: Repeated measures ANOVA found that active and placebo transcutaneous piezoelectric current elevated thresholds for warm sensation, heat pain, and cold sensation. However, there were no statistically significant effects for active piezoelectric current compared with placebo for any outcome measure. Conclusions: Reductions in experimentally induced pain were not due to piezoelectric currents per se. These findings challenge claims about the efficacy of transcutaneous piezoelectric currents for pain relief. A clinical trial is needed.