Medical Code: SGM-FS-006
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Condition: Depression

Prevalence: 15.7 million adults and 2.6 million adolescents in the US; or 6.7% of adults and 10.7% of adolescents

Layman’s Definition: Loss of signals to the brain about positive feelings, making the person feel sad, numb, and/or angry all of the time

Typical Age of Symptom Onset: 5-50

Primary Symptoms: Persistent feeling of hopelessness and despair. Lack of energy. Feeling tired all of the time. Feelings of worthlessness and/or a disbelief that the person will be able to cope with their situation and/or that others would be better off without them. A belief that the person’s life will not get better. Emotional numbness often with reduced sex drive. Flattened emotional response to both positive (happy) and negative (sad) life events. Thoughts of suicide.

Secondary Symptoms: Increased sleep, but often of poor quality.  Overeating or loss of appetite may lead to significant weight gain or loss.  Because of feedback between the emotional centers of the brain and pain centers, depressed individuals may experience non-specific aches and pains or a worsening of pain from other health conditions.  Individuals with depression may attempt to self-medicate their bodily or emotional pain with alcohol or other drugs and face increased risk of addiction. Because of feelings of worthlessness and hopelessness, depressed individuals may neglect their health and become ill from a range of conditions.  A person experiencing depression may isolate themselves from other people to avoid having to fake feeling OK. Some individuals with depression may also show anger towards others and/or make radical changes in their lives such as quitting a job, moving to a new city, or divorcing a spouse in the (mistaken) belief that changing their external circumstances will change their internal state.  Increased risk of suicide or suicide attempts.

Cause(s)/Risk Factor(s): The final common pathway for depression symptoms appears to be reduced levels of a neurotransmitter called serotonin in specific areas of the brain involved in emotions. The reduced serotonin levels may be due to damage caused by a stroke, Multiple Sclerosis (MS) lesion, neurotoxic effects of recreational drugs, damaging effects of elevated stress hormone levels, or other causes, including genetic factors. Some of the factors known to cause depression include:

  • B vitamin deficiency- often caused by dietary changes or reduced absorption with age
  • Medication side effects-especially in older people whose livers break down drugs more slowly and who may be taking several medications
  • Hormonal changes- particularly after childbirth (postpartum) or late in pregnancy; can also be caused by low thyroid hormone levels
  • Delayed effects of epileptic seizures
  • Stroke
  • MS lesions
  • Late symptom of many neurological conditions such as Parkinson’s Disease
  • Stressful events such as loss of a loved one, sudden disability, and loss of job or home
  • Genetic predisposition
  • Aging

Standard Treatment(s): If the depression is caused by another underlying health condition, treating the source is the preferred option. For example, if B vitamin deficiency or drug side effects are suspected, dietary supplements or discontinuing drugs or lowering their dosages may be recommended.  Depression caused by low thyroid function may be treated with thyroid hormone supplements. Postpartum depression may resolve over time, or hormonal treatments may be recommended. Better control of seizures may reduce depression caused by seizure activity.

The primary treatment for depression, however, is a class of drugs called serotonin selective reuptake inhibitors (SSRIs). These essentially keep more serotonin around longer in the areas of the brain where it should be present at higher levels than it is. SSRIs generally must be taken for several weeks before they become fully effective.

Other, older medications for depression, including tricyclic antidepressant or monoamine oxidase inhibitors (MAOIs) may be prescribed if SSRIs are ineffective or cause too many side effects, but these medications have their own side effects. Several different medications or medication combinations may need to be tried before finding an effective treatment that does not have too many unwanted side effects.

Cognitive therapy or cognitive behavioral therapy may be recommended to help the person with depression develop better strategies for managing life stress and block self-reinforcing negative thinking. A good relationship with a therapist is considered to be highly important to the effective treatment of depression because it is important for the depressed individual to communicate honestly about their mental processes and for them to take any prescribed medications long enough to be able to determine whether or not they are going to be effective.

The therapist may also wish to talk to family members about the person’s attitude and behavior for an independent assessment about how well the individual is functioning in his or her daily life.  Talk therapy plus medication is generally considered to be more effective than either treatment alone, but individuals may respond better to one or the other.  Electroconvulsive therapy (ECT) may be recommended as a last resort for individuals experiencing severe depression which does not improve with medication or talk therapy.

For more information about symptoms and treatment options for Depression, see:,, or

To better understand the experience of living with Depression, see:

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