Depression
Condition
(Major Depressive Affective Disorder; Unipolar Disorder; Unipolar Mood Disorder)
Definition
Depression is a mood disorder. It is marked by a lasting low mood, sadness, and lack of interest in activities. Bouts of depression can last for weeks, months, or years. Treatment often helps people recover.
Causes
The exact cause of depression is not known. It is likely due to environment, personal traits, and stress.
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Risk Factors
Depression is more common in women. Many things can raise the risk of depression such as:
- A personal or family history of depression or anxiety
- Long-term illness
- Childhood abuse, neglect, or trauma
- Alcohol and drug abuse
- Stress, loss, or major life changes
- Other mental illnesses or brain injury
- Partner abuse
- Little or no social support
Symptoms
Depression can differ from person to person. Some have only a few symptoms, while others have many. Symptoms can change over time and may include:
- Feelings of sadness, anxiety, or emptiness
- Loss of interest in hobbies, activities, or sex
- Feeling helpless, hopeless, or guilty
- Sleeping too much or too little
- Feeling tired, restless, or irritable
- Problems with focus, memory, or decisions
- Changes in eating or weight
- Thoughts of death or suicide
Sometimes there are physical symptoms. Examples are aches and pains that cannot be explained.
Diagnosis
The doctor will ask about symptoms and past health. A physical exam may be done. The doctor may give mental health exams. Tests may be done to rule out other causes.
Treatment
The goal is to ease symptoms and decrease effect on day to day life. Treatment depends on the type of depression and how severe it is. Severe depression may need hospital care. Care is urgent if someone might hurt themselves or others. Call or text 988 for the US National Suicide and Crisis Lifeline. They will connect you to a free counselor for support. If you are a Veteran, call 988 and then press "1".
Treatment may include a combination of the following:
- Medicines, such as:
- Antidepressants
- Mood stabilizers and antipsychotics—if needed
- Medicines for anxiety and sleep—usually short-term
- Ketamine as a nasal spray or IV—may be used if other options do not work
- Other medicines
- Counseling such as cognitive behavioral therapy and others—to improve coping
- Lifestyle changes such as:
- Healthy diet with B vitamins and omega-3 fatty acids—may help ease symptoms
- Daily exercise—may help boost mood
- Supplements, such as St. Johns wort and DHEA—may help some
Other treatments may be:
- Light therapy—sitting near an ultra-bright light for a certain time each day
- Sleep deprivation therapy—a short-term option that may improve mood
Sometimes symptoms are severe and other treatments do not work. In this case, options may be:
- Electroconvulsive therapy (ECT)—a brief electric pulse to the brain to help reset it
- Trascranial magnetic stimulation (TMS)—magnetic pulses aimed at certain brain regions
- Vagus nerve stimulation (VNS)—an implanted device that may alter signals to the brain
Prevention
There are no guidelines for depression prevention since causes can vary.
Depression and Bipolar Support Alliance
Mental Health America
CANADIAN RESOURCES:
Canadian Mental Health Association
Canadian Psychiatric Association
Depression and Bipolar Support Alliance
Mental Health America
CANADIAN RESOURCES:
Canadian Mental Health Association
Canadian Psychiatric Association
References
- Columbia University. Q&A on bright light therapy. Columbia University website. Available at: http://www.columbia.edu/~mt12/blt.htm.
- Depression. Mental Health America website. Available at: https://www.mhanational.org/conditions/depression.
- Depression. National Institute of Mental Health website. Available at: https://www.nimh.nih.gov/health/topics/depression.
- Depression alternative treatments. EBSCO DynaMed website. Available at: https://www.dynamed.com/management/depression-alternative-treatments.
- Kandola A, Ashdown-Franks G, et al. Physical activity and depression: Towards understanding the antidepressant mechanisms of physical activity. Neurosci Biobehav Rev. 2019;107:525-539.
- Major depressive disorder (MDD). EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/major-depressive-disorder-mdd.
- St. John's wort. EBSCO Natural and Alternative Treatments website. Available at: http://www.ebscohost.com/biomedical-libraries/natural-alternative-treatments.
- St. John's wort and depression; in depth. National Center for Complementary and Integrative Health website. Available at: https://www.nccih.nih.gov/health/st-johns-wort-and-depression-in-depth.
- St. John's wort for depression. EBSCO DynaMed website. Available at:https://www.dynamed.com/management/st-johns-wort-for-depression.
Contributors
- Adrian Preda, MD
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