Alternative medicine is any practice that is put forward as having the healing effects of medicine, but does not originate from evidence gathered using the scientific method, is not part of biomedicine, or is contradicted by scientific evidence or established science.
It consists of a wide variety of health care practices, products and therapies, ranging from being biologically plausible but not well tested, to being directly contradicted by evidence and science, or even harmful or toxic.
Examples include new and traditional medicine practices such as homeopathy, naturopathy, chiropractic, energy medicine, various forms of acupuncture, traditional Chinese medicine, Ayurvedic medicine, Sekkotsu, and Christian faith healing. The treatments are those that are not part of the science-based healthcare system, and are not clearly backed by scientific evidence.
Despite significant expenditures on testing alternative medicine, including $2.5 billion spent by the United States government, almost none have shown any effectiveness greater than that of false treatments (placebo), and alternative medicine has been criticized by prominent figures in science and medicine as being quackery, nonsense, fraudulent, or unethical.
Complementary medicine is alternative medicine used together with conventional medical treatment, in a belief not confirmed using the scientific method that it “complements” (improves the efficacy of) the treatment. CAM is the abbreviation for complementary and alternative medicine. Integrative medicine (or integrative health) is the combination of the practices and methods of alternative medicine with conventional medicine.