A psychiatrist is a medical physician who specializes in the diagnosis, treatment, and prevention of mental illness, including substance abuse and addiction.
Psychiatrists access both the mental and physical aspects of psychological disturbance.
Their medical training has provided them with a knowledge of the many causes for a patient's feelings and symptoms, enabling them to make a complete, accurate diagnosis and then recommend or provide treatment. Psychologists have a PhD, not a medical degree. Their training includes seven years of graduate work and at least two years of supervised clinical work. They possess a unique combination of scientific methods, along with substantial skills and experience in working with people who have real life problems. Psychologists study the science of human behavior, and then apply it, in a professional setting.