Relief of primary dysmenorrhea by transcutaneous electrical nerve stimulation.

In this study we describe the use of high-frequency transcutaneous electrical nerve stimulation (TENS) (100 Hz) and low-frequency TENS (lf-TENS) (2 Hz trains) as compared with placebo-TENS (p-TENS) in a group of 21 patients suffering from primary dysmenorrhea. Naloxone, a relatively pure opiate antagonist, was an additional test administered to 6 volunteer patients who had experienced an alleviation of pain with TENS. As will be seen, 14 out of 21 patients receiving high-frequency TENS (hf-TENS) experienced a pain reduction exceeding 50% of its original intensity. During lf-TENS or p-TENS, only 7 and 5 patients, respectively, obtained pain relief exceeding 50%. In 4 out of 6 volunteer patients, the relief of pain obtained with lf-TENS was counteracted by naloxone, whereas the relief experienced with hf-TENS in the same patients was, in general, unaffected by naloxone.