Certain drugs used alone or in combination can have side effects much like the symptoms of depression. The Common Types of Depressive Disorders Major Depression. It's possible for a person to have only one episode of major depression. However, it's more common for the episode to repeat several times during the person's life or to be long-lasting. This is depression that may result from changes in the season.
Most cases begin in the fall and winter.
They may function fairly well on a daily basis, but over time their work and relationships suffer. Fortunately, dysthymia can be successfully treated. The mood changes can be sudden, but are usually gradual. Therapists know more about depression than perhaps any other emotional illness. Because of research and medical advancements 80 to 90 percent of those with depressive disorder can be treated successfully.