In such cases, detection of depression can result in more effective treatment and a better outcome for the patient. Substance use must be discontinued in order to clarify the diagnosis and maximize the effectiveness of psychiatric interventions. Additional treatment is necessary if the depression remains after the substance use and withdrawal effects have ended. Individuals or family members with concerns about the co-occurence of depression with another illness should discuss these issues with the physician. Many factors can contribute to depression.
Some people become depressed for a combination of reasons.
For others, a single cause appears to trigger depression. Some become depressed for no apparent reason. Regardless of the cause, depression needs to be diagnosed and treated. Strokes, certain types of cancer, diabetes, Parkinson's disease, and hormonal disorders are examples of illnesses that may be related to depressive disorders. Some medicines cause depressive symptoms as side effects.