Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at March 15, 2016

Depression sometimes called major depression or clinical depression is an extremely common mental disorder. Although everyone feels “down” at certain times in their lives, particularly when dealing with losses or deaths, depression goes beyond ordinary sadness and can become an enormous problem that affects a person in all areas of life from work to relationships.


Definition & Facts

Depression is broadly defined as an illness consisting of persistent feelings of hopelessness, sadness, and a loss of interest in things that one previously enjoyed. Depression is a mental illness in that it is primarily about mood and behavior. It goes beyond normal sadness to permeate all aspects of life, leading to a generally "low" mood that cannot easily be lifted. Depression is usually accompanied by lower levels of activity and withdrawal from social life and activity.

There are also several different types of depression. Postpartum depression affects mothers up to a year after the birth of a child. Seasonal affective disorder or seasonal depression generally occurs in the winter, though this varies depending on the person. Bipolar disorder includes both depressive and manic symptoms. Manic symptoms cycle between depression and feelings of elation, sleeplessness, and risk-taking behavior.

Atypical depression is depression that looks largely like major depression, but involves the greater ability to react positively to enjoyable events. A person with atypical depression has the ability to "enjoy life" when something positive occurs, whereas individuals suffering from major depression often are unable to do this.

Depression commonly runs in families, indicating a possible genetic link. It is also commonly co-morbid, meaning that it often appears with anxiety and substance abuse.

Symptoms & Complaints

According to the DSM-5, the current diagnostic manual for mental health diagnosis, one must meet at least five of the following symptoms to be categorized as depressed:

  • A lack of energy
  • Overeating or loss of appetite
  • Oversleeping or lack of sleep
  • Sad or “empty” feelings that cause distress
  • Suicidal ideation or suicide attempts
  • Difficulty with concentration and memory
  • Loss of interest in once-pleasurable hobbies
  • Feeling restless or irritated
  • Feelings of guilt and worthlessness
  • Feeling pessimistic or hopeless about life
  • Loss of pleasure

While most people associate depression with feeling slow, low, and sleepy, depression can also include anxiety symptoms, such as irritation or restlessness, and some people with depression are sleepless and agitated.

Most severely, depression can be accompanied by suicidal ideation or parasuicidal behaviors (such as self-harm).


Most researchers believe that depression is caused by a malfunctioning of brain circuits that help to regulate mood and emotion, specifically problems with the production of chemical neurotransmitters such as serotonin, dopamine, and neurepinephrine.

Although the exact origins of depression are unclear, things that increase the likelihood of depression include a history of abuse, family history of depression, traumatic life events, or serious illness. The likelihood of developing depression is increased by stressful life situations, so those who are going through a divorce, grieving the loss of a loved one, dealing with substance abuse, or experiencing any other major stressor, should be aware of possible symptoms of depression.

Diagnosis & Tests

Because depression does not always look the same in every person, it is important to see a doctor for treatment when an individual feels a significant and distressing change in mood. Most importantly, those experiencing suicidal ideation or parasuicidal behaviors should seek help immediately.

Usually, an individual is diagnosed with depression after speaking with a health professional and describing symptoms. Depression can be diagnosed by a physician, psychiatrist, psychologist, counselor, or therapist.

There are several short, self-administered tests that are also given to individuals who might be depressed, including the Beck Depression Inventory. Those hoping to get more information about possible depression symptoms should come prepared for self-assessments and visits with a health care professional with an account of sleeping habits, moods, and any suicidal ideation or attempts. These details are necessary for a thorough assessment of depression symptoms and to rule out any medical causes for depressive symptoms.

Treatment & Therapy

Depression is most often treated with a combination of medication and therapy. Antidepressant medications have been found to be helpful for many people who suffer from depression, though some antidepressants have side effects such as suicidal ideation and weight gain.

Generally, depression is also treated with talk therapy also called psychotherapy. Some therapies for depression include digging into past events to find the source of depressive moods or thoughts, while other kinds of therapy examine thoughts and behaviors and seeks to "retrain" the mind to avoid dwelling on negative moods. A promising new avenue for depression treatment is mindfulness-based cognitive therapy (MBCT), in which clients are encouraged to track their somatic and mental experience and become more aware of negative mood.

Prevention & Prophylaxis

Although it is not always possible to identify the cause of depression, there are some steps researchers have identified that can lessen the likelihood of developing full-blown depressive symptoms. Exercise and healthy eating have been linked to a decrease in depression symptoms for many patients. Decreases in depressive symptoms also occur when depressed patients get enough sleep every night.

A common symptom of depression is a feeling of hopelessness, and a way to combat that feeling is to attempt to find meaning in life. This can mean seeking out volunteer work, participating in enjoyable hobbies, or reconnecting to activities that engage the senses.

Lastly, social isolation is a huge contributor to depressive mood. Although it can be difficult, depressed patients should be willing to reach out for help and support from family and friends during challenging times.