What is the difference between a psychologist and a psychiatrist?

The simplest way to describe the difference between a psychiatrist and a psychologist is that a psychiatrist is a medical doctor, while a psychologist is not. The suffix “-iatry” means “medical treatment,” and “-logy” means “science” or “theory.” So psychiatry is the medical treatment of the psyche, and psychology is the science of the psyche.

A psychologist primarily aids their patients through counselling and psychotherapy. He or she  may sometimes hold a doctoral degree (Ph.D.) and be called “doctor,” but is not a medical doctor (M.D.).

A psychiatrist, on the other hand, is a medical doctor, and while he/she may also perform psychotherapy, he/she can additionally prescribe medications and perform medical procedures such as electroconvulsive therapy (ECT).

Both kinds of professionals treat people with problems that vary widely by degree and type, from mild anxiety to schizophrenia. Both can practice psychotherapy, and both can do research.