What Is Clinical Depression?

The Description, Causes, and Treatment of Depression

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In order to understand what clinical depression is, one must first understand that depression can exist in a continuum of severity, ranging from milder, more transient depressed mood states to more severe, chronic forms. When depression passes into the more severe end of the spectrum and requires professional treatment, it can be referred to as clinical depression.

There are two primary types of clinical depression:

Major Depression

This type of depression, also known as major depressive disorder or unipolar depression, is what people usually think of when they think of depression. Major depression is characterized by the following symptoms:

  • Feelings of sadness or emptiness
  • Loss of interest in previously enjoyed activities
  • Weight and appetite changes
  • Sleep problems
  • Feelings of being either slowed down or excessively agitated
  • Tiredness and lack of energy
  • Feelings of worthlessness or guilt
  • Problems with concentration and making decisions
  • Thoughts of death or suicide

The Depressive Phase of Bipolar Disorder

Clinical depression is also a part of an illness called bipolar disorder. People with bipolar disorder tend to alternate between periods of depression and periods of greatly elevated mood called mania. During the depressive phase of the illness, the symptoms may be very similar to those of major depression. However, during the manic phase, a person may experience symptoms at the opposite end of the scale, such as:

  • Increased energy
  • Sleeplessness
  • Irritability
  • Rapid speech
  • Hypersexual behavior
  • Racing thoughts
  • Grandiose ideas
  • Greatly increased activity
  • Impulsivity
  • Poor judgment


The causes of depression are not completely understood, but it is believed that several different factors may work together to make an individual more prone to developing it. Some studies point to the fact that depression may be an inherited condition in which certain mood-regulating chemicals in the brain called neurotransmitters do not work properly. It appears that environmental factors may also play a role, possibly by triggering the illness in people who are already genetically vulnerable.


The usual first choice for treating depression is antidepressant medications. There are several different types of antidepressants available; however, those belonging to a class called selective serotonin reuptake inhibitors (SSRIs) are probably the most often prescribed. They are generally preferred by both doctors and patients because they tend to have fewer and less bothersome side effects than certain older types of antidepressants.

Psychotherapy is another popular choice for treating depression, both on its own and combined with medication.

Psychotherapy involves a therapist working with patients—either alone or in a group setting—to help them recover from their illness. In working together, they try to tackle personal issues and problems that may be contributing to their depression.

Psychotherapy can be especially beneficial for those with depression, as it helps patients better understand themselves and how they can manage their illness.

One type of psychotherapy in particular—cognitive behavioral therapy—has quite a bit of research suggesting that it is a very effective treatment for clinical depression.

Some studies indicate that a combination of medication and psychotherapy may be the best option for treating depression. The combination of the two attacks depression from two different angles, addressing both the underlying chemical imbalance as well as the psychological factors involved in the illness.

Talk to a mental health care practitioner to figure out the most appropriate treatment plan for you.

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Article Sources

  • "Mental Health Medications." National Institute of Mental Health. 2008. National Institutes of Health.
  • Hall-Flavin, David K.  "What Does the Term 'Clinical Depression' Mean?"  Mayo Clinic.  April 21, 2011.  Mayo Foundation for Medical Education and Research. 
  • Moore, David P. and James W. Jefferson, eds. Handbook of Medical Psychiatry 2nd ed. Philadelphia: Mosby Elsevier, 2004.