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Denise Millstine

, MD, Mayo Clinic

Last full review/revision Sep 2018| Content last modified Sep 2018

Acupuncture, a therapy within traditional Chinese medicine, is one of the most widely accepted complementary therapies in the western world and is often part of integrative medicine. Specific points on the body are stimulated, usually by inserting thin needles into the skin and underlying tissues. Stimulating these specific points is believed to affect the flow of qi (a universal life force) along energy pathways (meridians) and thus restore balance.

The procedure is generally not painful but may cause a tingling sensation. Sometimes stimulation is increased by twisting, warming, or otherwise manipulating the needle.

Acupuncture points may also be stimulated by

  • Pressure (called acupressure)
  • Lasers
  • Ultrasound
  • A very low voltage electrical current (called electroacupuncture) applied to the needle

(See also Overview of Integrative, Complementary, and Alternative Medicine.)

Evidence and Uses of Acupuncture

Acupuncture research is inherently difficult to conduct. Blinding is challenging and so-called "sham" acupuncture often puts pressure on acupressure points, thereby creating a different treatment experience that may not be truly inert. In some regions, particularly in China, published acupuncture studies tend to show a more positive effect. This may reflect bias, but it could also be that these providers are practicing the full schema of traditional Chinese medicine of which acupuncture is only a component.

The World Health Organization (WHO) has helped with this clinical challenge by issuing a list of conditions for which they have deemed evidence of efficacy to be strong or available but for which additional study is recommended, including

  • Symptoms of cancer therapy
  • Depression
  • Dysmenorrhea
  • Pain
  • Headache
  • Hypertension
  • Post-operative symptoms
  • Some complications of pregnancy
  • Stroke complications

Possible Adverse Effects and Contraindications

Adverse effects of acupuncture are probably underreported, although treatments are generally safe. A 2012 review of adverse effects that were reported after acupuncture noted the following (1):

  • Retained needles (31%)
  • Dizziness (30%)
  • Loss of consciousness or unresponsiveness (19%)
  • Falls (4%)
  • Bruising or soreness at the needle site (2%)
  • Pneumothorax (1%)
  • Other adverse effects (12%)

Most (95%) were classified as causing little or no harm.

When correctly done, acupuncture is fairly safe, but skill and care vary among practitioners.


  • 1. Wheway J, Agbabiaka TB, Ernst E: Patient safety incidents from acupuncture treatments: a review of reports to the National Patient Safety Agency. Int J Risk Saf Med 24(3):163–9, 2012.

More Information

  • Acupuncture: Review and Analysis of Reports on Controlled Clinical Trials, 2002—WHO's list of symptoms, diseases, and conditions that have been shown through controlled trials to be treated effectively by acupuncture, made available by the British Acupuncture Council

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