To begin with you should understand the differences between various kinds of mental health practitioners. Dr Karen Froming explains the differences in her column at Ask Our e-Psychologist . This column will have contributors who are psychologists and psychiatrists. The main thing that differentiates them from other mental health professionals is their reliance on the scientific literature and research to inform what they do. I can use herbal medicine to illustrate.
Western medicine is grounded in medical research.
New drugs undergo rigorous testing and must be approved by the Federal Drug Administration. To be approved, they need to demonstrate that they do what they claim to do. They also need to show that they do not have serious negative side effects. Herbal medicines come out of a folk tradition. Some have been used for centuries but many of the claims associated with them have never been subjected to careful evaluation.