Several scientific studies have shown that CES, in treating pain related stress, has been effective in treating many different types of pain. In 1989, 23 chronic pain patients who had experienced intractable pain for more than 18 months were treated with CES for 20 minutes a day for two weeks. It was found that initially their serotonin and norepinephrine levels were significantly lower than those of normal controls, and that these were elevated significantly following CES treatment. That change was accompanied by a significant improvement in subjective pain response in 44% of the patients, with no other treatment than CES.

There have been several other studies in which CES was used successfully to treat headaches from tension headache to migraines. In migraine headaches, it was found that in the weeks following CES treatment, the patients suffered fewer migraine episodes, and when these did occur, the pain was much less intense than previously. Tension headaches responded readily to CES treatment.