There are so many different words to describe depression that it can be hard to keep them all straight. Major depressive disorder refers to what is known as "clinical depression." Clinical or major depression can only be diagnosed by a doctor.

Clinical depression can appear to come out of nowhere, all at once. It can last for a short time or it can reoccur over the years. When it is one episode, most people ignore it and get back to their daily lives. We most likely know someone who either has or will experience clinical depression at some point in their lives.

Depression knows no boundaries. It can occur in any racial group, any socio-economic group, and any religious group.  Age is also not a boundary.  Depression can affect the young as well as the old.  We are all in the same statistical pile when it comes to trying to predict who will be affected by a depressive disorder.

Each episode of depression may last for a few days, a few months, or even years. The longer depression lasts, the more likely it is to adversely affect your health and your life. A characteristic of major or clinical depression is its ability to interfere with your normal day-to-day activities. Other depression-related disorders like seasonal affective disorder (SAD) and dysthymia are not likely to cause the same extent of disruption in your life.

A depressive episode of this order affects the way you think, behave and see the world around you. People who have experienced clinical depression describe it as living in a deep dark hole that they can't climb out of. Some describe the feeling as a black veil draped over their lives. Either way, these feelings are too serious to ignore.   Seeking professional help is a must.

Major or clinical depression involves a chemical imbalance in the brain. That's why simply trying to hang in there until the dark feelings pass doesn't work.  Even if you get through this episode and return to your normal day-to-day life, another episode will be waiting for you further down the road. Recovering from clinical depression requires treatment.

Here is a simple overview of how clinical depression develops. In the brain, different chemicals or hormones called "neurotransmitters" bind to receptors in the brain. They control mood and emotion. Norepinephrine, serotonin and dopamine are a few of these neurotransmitters that send messages throughout the brain and body. When there is a deficiency in these neurotransmitters, signals can get crossed or not delivered at all. Depression can result.

If you or someone you love is experiencing any of those "dark" feelings that just don't seem to get any better, clinical depression could be the problem. There are many treatment options available to give you back your life, so talk to your doctor today.