Orthomolecular psychiatry is the use of orthomolecular medicine for mental illness. Orthomolecular psychiatry has been rejected by evidence-based medicine and has been called quackery. The approach uses unorthodox forms of individualized testing and diagnosis to attempt to establish an etiology for each patient's specific symptoms, and claims to tailor the treatment accordingly, using a combination of nutrients, dietary changes and medications that are claimed to enhance quality of life and functionality as well as to reduce or eliminate symptoms and the use of xenobiotic drugs. Scientific studies have shown mixed results; although there are some promising results from nutritional psychiatry, some forms of orthomolecular psychiatry are ineffective.