Complementary and alternative medicine (CAM) is the term for medical products and practices that are not part of standard care. Standard care is what medical doctors, doctors of osteopathy, and allied health professionals, such as nurses and physical therapists, practice.
Complementary medicine is used together with standard medical care. An example is using acupuncture to help with side effects of cancer treatment.
Alternative medicine is used in place of standard medical care. An example is treating heart disease with chelation therapy (which seeks to remove excess metals from the blood) instead of using a standard approach.
The claims that CAM treatment providers make can sound promising. However, researchers do not know how safe many CAM treatments are or how well they work. Studies are underway to determine the safety and usefulness of many CAM practices.
To minimize the health risks of a CAM treatment
NIH: National Center for Complementary and Alternative Medicine