Effect of acupuncture of pain threshold and pain tolerance determined by electrical stimulation of the skin: a controlled study.

The effect of needling traditional acupuncture loci (Ho-Ku, LI4; Nei-Kuan, EH-6) compared to arbitarily chosen points was measured in twelve healthy subjects. In a crossover blind study pain tolerance and pain threshold were measured by electrical stimulation of the skin in the thyroid area. Traditional acupuncture was found to be significantly more effective in elevating pain threshold than needling of arbitarily chosen points. Pain tolerance also rose more under "real" acupuncture, the difference, however, being statistically not significant. In one subject, threshold and tolerance increased more under needling of nonacupuncture loci, while two subjects did not show any changes under either procedure.