What is Major Depressive Disorder?

Introduction

Major depressive disorder (MDD), also known simply as depression, is a mental disorder characterised by at least two weeks of pervasive low mood. Low self-esteem, loss of interest in normally enjoyable activities, low energy, and pain without a clear cause are common symptoms. Those affected may also occasionally have delusions or hallucinations. Some people have periods of depression separated by years, while others nearly always have symptoms present. Major depression is more severe and lasts longer than sadness, which is a normal part of life.

The diagnosis of MDD is based on the person’s reported experiences and a mental status examination. There is no laboratory test for the disorder, but testing may be done to rule out physical conditions that can cause similar symptoms. Those with MDD are typically treated with counselling and antidepressant medication. Medication appears to be effective, but the effect may only be significant in the…