A systematic review by American authors of 31 separate studies looking at acupuncture for chronic headache, has found that the majority of trials comparing real with sham acupuncture as a control, suggest true acupuncture is significantly more effective. This remains true at both early and late follow-up. The combined data showed acupuncture to be superior to medication for headache intensity, frequency, physical function and overall treatment response rate.
(Acupuncture for the Management of Chronic Headache: A Systematic Review. Anesthesia & Analgesia Journal, December 2008.)