Analgesic effects of different acupoint stimulation frequencies in humans.

Transcutaneous electrical acupoint stimulation (TEAS) provides a convenient and standardized technique for pain treatment. The cold-pressor test is a simple and reliable model in humans for the induction of tonic pain. In this controlled study, the effects of TEAS on cold pressor-induced pain were evaluated in 22 healthy human subjects. Electrical stimulation at 4 Hz and 32 Hz was applied to He-Gu (LI 4) and Nui-Guan (P 6) acupoints for 15 minutes. Pain score ratings were evaluated at four time points from 30-170 seconds during the cold-pressor test. We observed an analgesic effect at both 4 Hz and 32 Hz of stimulation, and pain score rating reductions were statistically significant compared to control (p < 0.01). Our data support the efficacy of TEAS analgesia. However, there was no significant difference between pain scores at 4 Hz and 32 Hz stimulation.