No, Reiki complements all other types of medical and therapeutic treatments. Reiki treatment should not be used as a substitute for consultation of a physician, a practitioner of natural therapeutics or a psychotherapist. Reiki can increase the efficacy of other types of healing. Reiki will improve the results of all medical treatment, acting to reduce negative side effects, shorten healing time, reduce or eliminate pain, reduce stress, and help create optimism.
-Cleveland Clinic; International Center for Reiki Training