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An Overview of Depression

If you fail an important examination, lose a loved one or a job, or get dumped in a relationship, it is normal to feel depressed. But if you remain depressed for more than two weeks, long after the event has passed, then you may have a common clinical disorder called depression. Clinical depression, also called major depressive disorder, is characterized by a sad or blue mood that affects nearly every aspect of your life every day – your family and social relationships, your work or school performance, even your desire to do simple things such as exercise or go out with friends.

Depression is much more than just a bad mood, though. Countless people in the throes of depression often feel worthless, lack any appetite, withdraw from friends and family, have difficulty sleeping, and can become agitated or lethargic. Most worrisome of all, people who are depressed can often run a high risk of suicide.

But depression, even though it often feels like it for a person who is depressed, is not the end of the world. It is one of the most well-understood and readily treated and treatable mental disorders. Learning more about this issue is an important and courageous first step toward ending feelings of sadness and depression.

What causes depression?

Like most mental disorders, the causes of depression are largely unknown. Researchers and clinicians theorize that depression is the result of three related factors – biological, psychological and social. No doctor can tell you how much of any single factor is contributing to the diagnosis of depression within an individual. For some people, the biological factors, such as genetics, may be stronger than the other two. For others, it may be caused mainly by a psychological issue, such as one’s personality or way of coping with stress.

Theories about biological causes include ideas such as there is a chemical imbalance in the brain, or that some people carry a genetic predisposition to depression based upon certain genes inherited from one’s parents. Theories about psychological causes include ideas such as there is an internal dialogue that reinforces our negative beliefs about ourselves or our abilities, or that some people never learn adequate coping skills as they are growing up. Theories about social causes include ideas such as a person may have had difficulty establishing social skills in childhood, or have few or no friends or family connections as an adult.

What are some of the Risk Factors for Depression?

A risk factor is something that may increase your chances of getting depression or another condition. The risk factors for depression include:

  • Having previous episodes of depression or another mental disorder (such as anxiety, a sleep disorder, or a personality disorder)
  • Any life-altering or stressful event in your life (including both negative ones, such as the death of a loved one, or positive ones, such as the birth of a child or a wedding)
  • A family history of depression (or some other mental disorders within your family)
  • Being a woman or elderly
  • Chronic illnesss of any kind
  • Low self-esteem or having no or few friends
  • Feeling helpless or having little control over a situation in your life

Symptoms of Depression

A person who suffers from a major depressive disorder either have a depressed mood or a loss of interest or pleasure in daily activities consistently for at least a 2 week period. This mood change affects a person across all aspets of their life – social, work, school and such.
Clinical depression is characterized by the presence of the majority of these symptoms in a person, experienced nearly every day:

  • Depressed mood most of the day, as indicated by either the person’s own feeling (e.g., feeling sad or empty) or as observed by others (e.g., appears tearful). (In children and adolescents, this may be characterized as an irritable mood.)
  • Markedly diminished interest or pleasure in all, or almost all, activities most of the day
  • Significant weight loss when not dieting or weight gain (e.g., a change of more than 5% of body weight in a month), or decrease or increase in appetite
  • Can’t sleep (insomnia) or sleeping too much (hypersomnia)
  • Can’t sit still (psychomotor agitation) or have difficulty with physical movement (psychomotor retardation)
  • Fatigue or loss of energy
  • Feelings of worthlessness or excessive or inappropriate guilt
  • Diminished ability to think or concentrate, or indecisiveness
  • Recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan, or a suicide attempt or a specific plan for committing suicide

Certain medications or medical conditions can cause symptoms similar to depression, but depression is generally not diagnosed when the symptoms can be traced back to a specific medication or medical condition.

Diagnosis of depression

While you can take an online screening quiz to see if you might have symptoms associated with depression, such quizzes are not reliable for a diagnosis. Depression is usually diagnosed through a clinical interview by a trained mental health professional, such as a psychologist or psychiatrist. Family doctors and general physicians can also make a diagnosis of depression, but they should always refer you to a mental health professional for follow-up care.
Since there are no laboratory or blood tests for depression, a clinical interview is designed to check for the symptoms of depression, determine any alternative diagnoses (such as a medical condition) that might better account for the symptoms, and suggest a course of treatment that will work best for an individual’s needs. Such interviews generally take an hour or an hour and a half to conduct and work best when the person is completely honest with the therapist or doctor.

Treatments for Depression

Once accurately diagnosed, depression is readily treated with a combination of medications and psychotherapy. Most people find relatively quick relief with medications, while psychotherapy can help a person learn to combat some of the issues that help contribute to depression. Depression treatment allows a person to feel better more quickly than on their own. It also often teaches important life skills and techniques to help a person in many different areas of their life, which may help prevent future recurrence of depression.

There are four major classes of antidepressant medications: selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants, monoamine oxidase inhibitors (MAOIs), and others. Most Americans are typically prescribed an SSRI antidepressant medication to begin with because they are fairly safe and effective. SSRIs include medications such as fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), citalopram (Celexa), or fluvoxamine (Luvox). Tricyclic antidepressants are older, but are better tolerated in some people. Some tricyclic medications include: imipramine (Tofranil, Janimine), doxepin (Adapin, Sinequan), and clomipramine (Anafranil). MAOIs are rarely prescribed in the U.S. because of their special diet requirements, but include medications such as phenelzine (Nardil) and tranylcypromine (Parnate). Other antidepressants that are also commonly prescribed for depression in the U.S. include venlafaxine (Effexor), nefazodone (Serzone), mirtazapine (Remeron), and buproprion (Wellbutrin).

A doctor chooses a medication based upon his or her previous experience and judgment about what is best suited for the needs of the specific depressed individual. Often when one medication is found to be ineffective, the doctor will discontinue the medication and try another. Most antidepressant medications can take anywhere from 4 to 12 weeks to become fully effective.

Psychotherapy is the second important component of depression treatment. Although there are a wide variety of psychotherapies available for the treatment of depression, the most commonly used types are cognitive-behavioral and interpersonal, or some combination of the two. Cognitive-behavioral therapy emphasizes learning more about how thoughts and feelings interact in most people, how to identify irrational or unproductive thoughts, and how to change those thoughts for the better. Interpersonal therapy focuses on the way a person communicates with others in their lives and seeks to improve those communication patterns through a number of techniques.

Most modern psychotherapies, such as cognitive-behavioral or interpersonal, are time-limited and goal-focused. This typically means therapy takes place once a week for about an hour, for anywhere between 15 and 25 weeks. Psychotherapy requires active, willing participation and work on the part of the individual; it is not a passive exercise where the therapist “does something” to make the person feel better.

Support groups and learning more about depression are two additional important components to many people’s treatment. Online or support groups within your local community are a popular method to find others experiencing similar issues and connect with them without feeling self-conscious or embarrassed about your condition. Learning more about your condition, through online resources or self-help books, gives many people new ideas and more strategies for coping with depression in their lives.

What do I do next about my Depression?

You’ve taken the first step in learning briefly about depression. If you’d like to learn more about depression, please check out our Depression In-Depth content. There you will find dozens of related articles helping you better understand depression and what you can expect in diagnosis, treatment, and ongoing care.

Keep in mind that depression is readily treated when correctly identified and a person receives ongoing care from a professional.

An Overview of Depression

John M. Grohol, Psy.D.

Dr. John Grohol is the founder and Editor-in-Chief of Psych Central. He is an author, researcher, and expert in mental health online, and has been writing about online behavior, mental health and psychology issues since 1995. Dr. Grohol has a Master's degree and doctorate in clinical psychology from Nova Southeastern University. Dr. Grohol sits on the editorial board of the journal Computers in Human Behavior and is a founding board member of the Society for Participatory Medicine. You can learn more about Dr. John Grohol here.

APA Reference
Grohol, J. (2018). An Overview of Depression. Psych Central. Retrieved on February 28, 2020, from
Scientifically Reviewed
Last updated: 8 Oct 2018 (Originally: 17 May 2016)
Last reviewed: By a member of our scientific advisory board on 8 Oct 2018
Published on Psych All rights reserved.