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Other common name(s): Reiki healing, Usui system of Reiki, distant Reiki

Scientific/medical name(s): none


Reiki is based on the belief that spiritual energy can be channeled through a Reiki practitioner to heal the patient's spirit. This is thought to help release the body's natural healing powers. Reiki is most often given as a hands-on treatment, but it may also be sent from a distance. The word Reiki comes from Japanese terms that translate as "universal life energy."


There are anecdotal reports that Reiki increases relaxation and sense of well-being. Some evidence suggests that Reiki may help reduce pain in patients with advanced cancer, but past studies of Reiki have not generally been rigorously designed and controlled. Other studies have shown no reduction in pain.

Available scientific evidence does not support claims that Reiki can treat cancer.

How is it promoted for use?

Many practitioners explain that Reiki is not used to diagnose or treat specific illnesses. Rather, Reiki is said to promote relaxation, decrease stress and anxiety, and increase a person's general sense of well-being. The Reiki practitioner delivers the therapy through his or her hands, with the goal of raising the amount of universal life energy (called qi, ch'i, or ki) in and around the client. Reiki supporters claim that when the energy paths of the body are blocked or disturbed, the result can be illness, weakness, and pain. Reiki practitioners intend to strengthen the flow of energy, which they say will decrease pain, ease muscle tension, speed healing, improve sleep, and generally enhance the body's ability to heal itself.

What does it involve?

During a Reiki session, the practitioner places his or her hands in 12 to 15 positions on or above parts of the patient's clothed body. The hands are intended to be a conduit for universal life energy, balancing energy within and around the body. The hands are held in place for approximately 2 to 5 minutes in each position. A Reiki session usually lasts about an hour. Some practitioners say that they achieve the best results when patients have 3 Reiki sessions within a relatively short time, take a break, and then repeat the process. There are 3 levels of Reiki practice. A Reiki I practitioner can offer hands-on sessions; a Reiki II practitioner can offer hands-on or distant Reiki; and a Reiki master can offer hands-on Reiki, distant Reiki, and Reiki instruction. The second degree Reiki practitioners and Reiki masters believe that they can send healing universal life energy over any distance, similar to claims by qigong masters who practice traditional Chinese healing concepts.

What is the history behind it?

The basis for modern-day Reiki practice may have started in Tibet more than 2,500 years ago. Reiki was rediscovered in the early 1900s by a Japanese man named Dr. Mikao Usui. During a lengthy period of travel and research, Dr. Usui found ancient texts that described Reiki and its power to heal by using the energy that flows through all living things. From his studies and meditations, he developed what came to be known as the Usui system of Reiki. Other systems of Reiki have been developed as well.

Training programs and certification are available from Reiki organizations. However, these organizations are not regulated by any government agency.

What is the evidence?

There are many individual (anecdotal) reports about Reiki's power to increase feelings of well-being and refresh the spirit. Some patients who were getting cancer treatment have reported an increased sense of well-being, with less pain, nausea, and vomiting after Reiki sessions. One small controlled pilot study found that Reiki was linked with reduced self-reports of pain in patients with advanced cancer, but it had no effect on the amount of pain medicine used by the patients to control their pain.

A nonrandomized study reported that Reiki improved anxiety among women after undergoing a hysterectomy. On the other hand, a randomized study reported no effect on anxiety of women undergoing breast biopsies.

A 2008 study looked at 100 people with pain due to fibromyalgia, using Reiki treatments or sham treatments twice a week. Researchers double-checked to be sure that the participants didn't know whether or not they got Reiki. In the end, they found no difference in pain between those who got Reiki and those who got something that looked like Reiki.

Many studies of Reiki have been conducted without using rigorous scientific methods, so quality information is scarce. For instance, studies that do not use a placebo group (using sham Reiki and identical conditions) are more likely to show symptom improvement shortly after treatment. But studies without placebo control leave open the possibility that the outcome is produced by mental and physical factors other than Reiki.

Available scientific evidence at this time does not support claims that Reiki can help treat cancer or any other illness. More study may help determine to what extent, if at all, it can improve a patient's sense of well-being.

Are there any possible problems or complications?

Reiki involves very light touch or no touch and is considered safe. However, relying on this type of treatment alone and avoiding or delaying standard medical care for cancer may have serious health consequences.

To learn more

More information from your American Cancer Society

The following information on complementary and alternative therapies may also be helpful to you. These materials may be found on our Web site (www.cancer.org) or ordered from our toll-free number (1-800-227-2345).

Dietary Supplements: What Is Safe?

The ACS Operational Statement on Complementary and Alternative Methods of Cancer Management

Complementary and Alternative Methods and Cancer

Placebo Effect

Learning About New Ways to Treat Cancer

Learning About New Ways to Prevent Cancer


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Note: This information may not cover all possible claims, uses, actions, precautions, side effects or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for consultation with your doctor, who is familiar with your medical situation.

Last Medical Review: 04/14/2011
Last Revised: 03/08/2012