Major Depressive Disorder

In order to be diagnosed with Major Depressive Disorder (MDD), an individual needs to have experienced at least one Major Depressive Episode. Some people experience mild symptoms of depression or a mix of anxiety and depression prior to developing MDD. If left untreated depression can last for several months or even longer. A subset of individuals with severe depression experience Psychotic Features which are abnormal perceptions (i.e., voices, visions) or hold odd or unusual beliefs that are not present when the individual is not depressed.

Approximately 10-25% of women and 5-12% of men will experience MDD. The average age at which most people first experience major depression is in their mid 20s. At least 60% of people who have experienced a Major Depressive Episode go on to have a second episode. Those who have had two episodes have approximately a 70% chance of a third episode and those who have had three episodes have a 90% chance of a fourth episode. Therefore, it is important to receive appropriate treatment as early as possible in the course of depression.

The seriousness of suicidal thoughts cannot be overstated. Although suicide may appear to be the only option at the time people usually regret having attempted suicide once they recover from depression, especially because of the immense impact of suicide on friends and family. If you are considering suicide visit your family physician or local emergency department immediately or call your local Distress Line.

A diagnosis of MDD is not given if the individual has experienced a Manic Episode, Mixed Episode, or a Hypomanic Episode. In such cases a diagnosis of Bipolar Disorder may be warranted. Approximately 5-10% of people who have experienced a Major Depressive Episode subsequently experience a Manic Episode.

There are a number of Physical Conditions that can cause symptoms similar to a Major Depressive Episode. Consult with a physician that you trust in order to have a full medical examination prior to concluding that what you are experiencing is depression without any physical basis.


Current research indicates that depression can be treated effectively with medications or psychotherapy. However, some forms of psychotherapy appear to have a lower rate of relapse than medications. In particular, individuals who have gone through Cognitive Behavior Therapy (CBT) appear be less likely to experience subsequent depressive episodes. People are taught how to change the negative thoughts they have about themselves, their future, and others. Often these thoughts are tied to past negative experiences, but occur in the present as a result of recent experiences. However, the person is usually harder on him or herself than the situation would warrant. CBT also involves teaching the person to approach life in a way that will reduce symptoms and get the person back doing the things that he or she enjoyed when not depressed.