Medically Reviewed By William C. Lloyd III, MD, FACS
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What is depression?

Depression, also known as clinical depression, is a mental health disorder that often involves an imbalance of the chemicals that support brain function. Depression is more than just feeling sad or having the blues for a few days. Clinical depression is a mood disorder commonly involving feelings of sadness, loss, anger, frustration or despair that interfere with everyday life for an extended period.

Depression is a common condition that can negatively affect a person’s ability to go to work and school, care for family, and take care of basic needs. More than 20 million people in the United States have depression, according to the National Institutes of Health.

Depression is often thought of as experiencing feelings of sadness, “having the blues,” or being disheartened. However, normal feelings of sadness generally resolve with time. For people with depression, feelings of sadness linger and intensify to the point that they interfere with a person’s ability to function normally. This in turn can intensify the depression.

Most people with depression do not seek assistance from a mental health professional, but they continue to visit their primary care provider. Frequently, through denial or misapprehension, there is reluctance to seek help for depression. It is important to understand that depression is not a sign of weakness. People who suffer from depression can’t simply make themselves feel better and happy again.

The good news is there are effective treatments for depression. If you are feeling depressed for two or more weeks, contact your healthcare provider to discuss the many treatment options for depression, as well as self-care steps that can help in your treatment.

A serious complication of depression is suicidal thoughts or actions. Seek immediate medical care (call 911) if you, or someone you are with or know, are having or expressing feelings of wanting to hurt or kill oneself or another person.

What are the different types of depression?

There are many types of depression including:

  • Major depression is the most intense and serious type of depression.
  • Persistent depressive disorder (dysthymia) is a less severe type of depression that is not as disabling as major depression, but is long-lasting and negatively affects your feelings of well-being and your ability to function effectively in daily living activities.
  • Postpartum depression is a type of depression that sometimes occurs after childbirth.
  • Seasonal affective disorder is depression that coincides with late fall and winter, when there is less sunlight, and gets better during spring and summer.

Depression may also be part of another disorder, such as bipolar disorder. People with bipolar disorder have periods of depression mixed with periods of mania, which is an extreme high.

What are the symptoms of depression?

The severity and types of symptoms of depression vary from person to person. Depression is more than just feeling sad or “having the blues.”  It is normal to experience temporary feelings of sadness or “feeling down” in reaction to difficult situations in life, such as losing a job or having a death in the family. Normal feelings of sadness, although painful, generally resolve after a short time.

For people with depression, feelings of sadness linger and intensify to the point that they interfere with the person’s normal routine. Symptoms of depression can make it difficult to work, enjoy time with friends and family, or even carry out basic activities of daily life. These effects in turn can make depression worse and cause symptoms to progress.

Typical symptoms of depression can include one or more of the following, especially if they do not go away or get better with time:

  • Aches, pains, headaches or digestive problems
  • Anger or irritability
  • Anxiety
  • Boredom
  • Difficulties with memory, concentration, or making decisions
  • Excess alcohol consumption
  • Feelings of worthlessness or guilt
  • Feelings of hopelessness and despair
  • Loss of interest in enjoyable activities
  • Low energy levels and fatigue
  • Sadness or melancholy
  • Sleep abnormalities, such as insomnia or a desire to sleep all the time
  • Weight gain or weight loss

Serious symptoms that might indicate a life-threatening condition

Any of the following symptoms can indicate worsening depression and a possible life-threatening situation. Seek immediate medical care (call 911) if you, or someone you are with or know, have any of these symptoms:

  • Having suicidal thoughts or thoughts of hurting oneself or others
  • Making a written plan to hurt oneself, commit suicide, or hurt another person
  • Suicidal actions including dangerous behavior, such as playing choking games or Russian roulette, or overdosing on drugs
  • Talking about or threatening to hurt oneself or another person
  • Talking about suicide, wanting to die, or not wanting to live any longer

What causes depression?

The cause of depression is not known, but research shows multiple factors are associated with the development of depression. These include:

  • Chemical imbalances in the brain. An imbalance of brain chemicals called neurotransmitters, including serotonin, norepinephrine and dopamine, can play a role in depression. Neurotransmitters function within areas of the brain that regulate emotions and mood.
  • Genetics: Depression may run in families. Current research is searching for specific genes that may be involved in passing a tendency toward developing depression in family lines.
  • Medical issues: Thyroid disorders, chronic pain, and chronic illness may trigger depression.
  • Situational or environmental factors: These factors include traumas or stressors, such as the loss of a loved one, loss of a job, or a divorce. As life circumstances improve, the depression may or may not resolve.

Many patients with depression have physical symptoms, especially chronic pain. Depression and chronic pain are closely connected because mood and pain perception centers are both located in the same area of the brain. Both chronic pain and depression can deplete the body’s stores of endorphins and other neurochemicals that regulate mood and sensation. The depletion of the body’s stores of endorphins and other neurochemicals due to one condition leaves the body vulnerable to developing the other condition or a worsening of the other condition.

If you have chronic pain or depression, seeking treatment may improve symptoms and reduce your risk of developing the other.

People who have a poor self-image, who view themselves negatively, or who are easily overwhelmed by life challenges may be more likely than others to experience depression.

What are the risk factors for depression?

A number of factors are thought to increase your chances of having depression or are associated with depression. These include:

  • Alcohol or drug abuse
  • Being a woman, due to the hormonal changes of such events as puberty, menstruation, pregnancy, childbirth, perimenopause and menopause
  • Being an adolescent
  • Being elderly, especially an older person with chronic illnesses and disabilities
  • Chronic pain
  • Family history of depression
  • Having certain medical conditions, such as hypothyroidism, stroke, insomnia, type 2 diabetes, and vitamin D deficiency
  • Posttraumatic stress disorder (PTSD)
  • Smoking
  • The winter months, in those with seasonal affective disorder
  • Traumatic events or life stressors, such as the loss of a loved one, severe illness, loss of a job, or a divorce

Reducing your risk of depression

Not all people who are at risk will develop depression, but you may be able to reduce your risk for depression by:

  • Eating a healthy diet that is low in saturated fats and high in fiber, whole grains, and fruits and vegetables
  • Getting enough sleep, rest and relaxation
  • Getting outside and enjoying some sunshine (which gives you vitamin D)
  • If you drink alcohol, limiting intake to one drink per day for women and two drinks per day for men
  • Participating in a regular exercise program
  • Quitting smoking
  • Reducing excessive stress
  • Regularly participating in leisure activities or activities you enjoy
  • Seeking regular medical care and following your treatment plan for such conditions as hypothyroidism, stroke, insomnia, type 2 diabetes, and vitamin D deficiency

How do doctors diagnose depression?

Signs and symptoms of depression vary between people, which can make diagnosing the condition difficult. Doctors use a variety of psychiatric and depression tests to diagnose depression. Your primary healthcare provider may screen you for depression, and may or may not refer you to a psychiatrist for a full evaluation.

Depression-related tests may include:

  • Physical exam. Your physical and mental health are more connected than once thought. Your doctor will ask about your symptoms, when you first noticed the symptoms, and if they are making it difficult for you to work, socialize or carry out your day-to-day life. She will also ask about your lifestyle, including eating, drinking, exercise and sleeping habits. She may order blood work, especially a thyroid hormone test, to determine if your thyroid gland is functioning normally.
  • Psychiatric evaluation. Your doctor will ask you questions about your thoughts, feelings and behavior. A common question is if you’ve lost interest in your usual activities. Your doctor will likely ask if you ever have thoughts of hurting yourself or others.

The Diagnostic and Statistical Manual of Mental Disorders (version 5, or DSM-5) has a list of symptoms for a depression diagnosis. The individual must be experiencing at least five or more of the following criteria daily, for most of the day, and for at least two weeks in a row. One of the five must include “depressed mood” or “loss of interest in activities”:

  • Depressed mood most of the day. In children and adolescents, the criterion may be irritability.
  • Loss of interest or pleasure in almost all activities
  • Sleep disturbance (sleeping less or more than typical for you)
  • Psychomotor changes, such as agitation, restlessness, or slow thinking or movement
  • Fatigue or low energy
  • Feeling worthless or excessive, illogical guilt
  • Difficulty thinking, concentrating, or decision making
  • Recurrent thoughts of death or committing suicide (suicidal ideation)

What are the treatments for depression?

Depression is treatable, and the sooner you get a diagnosis and start treatment, the more effective treatment is likely to be. The overall treatment goal for people living with depression is to feel better and live functional and productive lives. Treatment may include a combination of depression medication, psychotherapy, lifestyle changes, and alternative therapies.


Commonly known as talk therapy, this type of therapy involves building a relationship with a counselor or psychotherapist. The therapist helps you address depression through cognitive behavioral therapy and other techniques. She teaches you the skills you need to recognize and work through issues that are encouraging depression. You will learn more effective ways of thinking and behaving in order to help change negative thoughts and behaviors.

You may need frequent visits at first, but as you gain more control you can increase the time between sessions.

Electroconvulsive therapy

People whose depression does not respond to more conventional treatments or who are experiencing psychotic episodes with depression may be candidates for electroconvulsive therapy (ECT). In the past, people called this technique electroshock therapy, or simply shock therapy. Modern ECT is a much safer, humane and effective procedure for various psychiatric conditions, including depression.


Antidepressant medicines treat depression by helping to correct an imbalance of brain chemicals called neurotransmitters, including serotonin, norepinephrine and dopamine. Neurotransmitters function within the areas of the brain that regulate emotions and mood.

Commonly prescribed types of antidepressants include:

  • SNRIs, serotonin and norepinephrine reuptake inhibitors, such as venlafaxine (Effexor)
  • Tricyclic antidepressants, such as imipramine (Tofranil)
  • MAOIs, monoamine oxidase inhibitors, such as isocarboxazid (Marplan), selegiline (Emsam) and phenelzine (Nardil)

Antidepressants have side effects, but are generally considered safe when taken as directed under medical supervision. However, some people, especially children, teenagers, and young adults may experience increased thoughts of suicide while taking certain antidepressants. Seek immediate medical care (call 911) if you, or someone you are with or know, are having or expressing feelings of wanting to hurt or kill oneself.

Antidepressants don’t work for everyone with depression. In some cases, psychiatrists prescribe a combination of medicines to treat depression if the antidepressant alone is not relieving symptoms. For example, they may prescribe an SSRI in combination with a medicine known as an atypical, or second generation antipsychotic. Aripiprazole (Abilify) and brexpiprazole (Rexulti) are examples. Atypical antipsychotics tend to have fewer side effects than first generation antipsychotics.

Treatment-resistant depression

Some people with depression develop treatment-resistant depression, which is defined as depression resistant to at least two different antidepressants. Esketamine, a form of the anesthetic drug ketamine, was recently approved by the Food and Drug Administration (FDA) for treatment-resistant depression. Esketamine is administered by nasal spray at a doctor’s office. People taking esketamine must also take an antidepressant, per the FDA approval.

What are alternative treatments and coping tips for depression?

You may be able to enhance the effectiveness of depression treatment with healthy lifestyle habits and alternative treatments. Many coping tips are thought to increase those “feel good” chemicals in the brain. People with depression (or prone to depression episodes) have found varying success with:

  • Acupuncture: This alternative form of medicine may reduce the severity of depression compared to no treatment. Acupuncture improved symptoms in pregnant women with major depressive disorder, compared to nonspecific acupuncture.
  • Journaling: Many people find solace in writing down their experiences, thoughts and feelings. It can also help you find patterns in your behavior or reactions to certain events. You can write every day, once a week, or whenever you feel like it.
  • Light therapy: People with seasonal affective disorder may especially benefit from this type of treatment. For 20 to 30 minutes a day, you sit by a light box that simulates natural sunlight. You’ll get the same effect by spending time outside in the sun.
  • Micro-productivity: Another way to describe breaking up large tasks into smaller pieces. You can help yourself feel less overwhelmed and frantic (and more productive!) by chunking large tasks or a lot of information into manageable parts. Ask your therapist or a trusted friend or relative if you need help in this area.
  • Regular exercise: It can help reduce feelings of depression by increasing the body’s supply of endorphins, chemicals in the body that increase the feeling of well-being. Pick something you like to do, whether that’s high-intensity workouts, yoga, or biking.
  • Socializing: You may not feel like socializing, but spending quality time with even one close, trusted friend or family member is an important part of recovering from any illness, including mental illness.

A popular herbal supplement that has been touted to treat depression is St. John’s wort. This herbal supplement is available without a prescription in the United States. St. John’s wort has been researched by the National Institutes of Health and was not found to be any more effective in treating major depression than a sugar pill. In addition, taking St. John’s wort can also seriously interfere with the effectiveness of other medications; therefore, it is important to consult with your healthcare provider before taking this supplement or any other supplement.

What are the potential complications of depression?

Complications of depression can be serious and even life-threatening in some cases. To minimize the risk of serious complications of depression, follow the treatment plan you and your healthcare professional design specifically for you.

Complications of depression include:

  • Decreased ability to function in work, school or daily life
  • Decreased sexual desire
  • Disability
  • Impaired social interactions
  • Migraine headaches, backaches and other chronic pain
  • Sleep disturbances
  • Social isolation
  • Suicidal thoughts or actions

Seek immediate medical care (call 911) if you, or someone you are with or know, are having or expressing feelings of wanting to hurt or kill oneself or another person.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 Feb 17
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
  1. Substance Abuse and Mental Health Services Administration. DSM-5 Changes: Implications for Child Serious Emotional Disturbance [Internet]. Rockville (MD): Substance Abuse and Mental Health Services Administration (US); 2016 Jun. Table 9, DSM-IV to DSM-5 Major Depressive Episode/Disorder Comparison. Available from:
  2. What Is Depression? American Psychiatric Association.
  3. Depression Basics. National Institute of Mental Health.
  4. Psychotherapies. National Institute of Mental Health.
  5. Sniezek DP, Siddiqui IJ. Acupuncture for Treating Anxiety and Depression in Women: A Clinical Systematic Review. Med Acupunct. 2013;25(3):164-172. doi:10.1089/acu.2012.0900.
  6. Smith CA, Armour M, Lee M, Wang L, Hay PJ. Acupuncture for depression. Cochrane Database of Systematic Reviews 2018, Issue 3. Art. No.: CD004046. DOI: 10.1002/14651858.CD004046.pub4.
  7. Monoamine oxidase inhibitors (MAOIs). Mayo Clinic.
  8. Integrative Behavioral Health. Anxiety and Depression Association of America.
  9. St. John’s Wort and Depression: In Depth. National Center for Complementary and Integrative Medicine.
  10. FDA approves new nasal spray medication for treatment-resistant depression; available only at a certified doctor’s office or clinic. U.S. Food & Drug Administration.