Health Topic

Depression

Depression is a serious medical illness. It affects almost 7 percent of U.S. adults. It causes feelings of sadness, hopelessness, and frustration that do not go away. Learn about treatments.

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Also called: Clinical depression · Dysthymic disorder · Major depressive disorder · Unipolar depression

Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Depression

Depression is more than a feeling of being sad or irritable for a few days. It's a serious mood disorder. As one of the most common mental disorders in the United States, depression can affect how you think, feel, and your everyday life. You may not know why you feel this way, but even basic daily activities such as sleeping, eating, or working may become difficult. Depression often needs long-term treatment but getting help at the earliest sign of a problem can help manage your symptoms.

The most common types of depression are major depression and persistent depressive disorder.

  • Major depression symptoms include a depressed mood or a loss of interest. Symptoms affect your daily activities and last for at least two weeks.
  • Persistent depressive disorder (also called dysthymia or dysthymic disorder) has less severe depressive symptoms, but they last longer, usually for at least two years.

Other types of depression can include:

  • Seasonal affective disorder comes and goes with the seasons. It usually starts in late fall and early winter and goes away during the spring and summer.
  • Bipolar disorder is sometimes called manic depression. This mood disorder can cause intense mood swings.
  • Depression with symptoms of psychosis is a severe form of depression that also has delusions (false beliefs) or hallucinations (seeing, hearing, or feeling something that isn't there).

There are a variety of things that may cause depression, including genetic, biological, environmental, and psychological factors. Depression can happen at any age and can affect anyone, but it's more common in women. This is often due to the physical and hormonal changes that women have during menstruation, pregnancy, the postpartum period, and menopause. Other mental disorders or chronic medical conditions such as diabetes, cancer, or heart disease may occur with depression. This may make the chronic condition or depression worse.

In some cases, there is no clear cause for depression.

You may be at a higher risk of depression if you have a close relative who has it or another mental health disorder. Going through trauma or stressful life events may raise your risk even more.

Depression doesn't look the same on everyone. The type and number of symptoms of depression can vary and don't always appear like sadness. Depression may affect you differently based on your:

  • Age. The symptoms of depression may be different in a child, who may appear more irritable than sad. Teens may act out or have excessive sleepiness. The symptoms for an older adult may not be as obvious as other age groups.
  • Sex. Men often show symptoms and coping behaviors differently than women. Rather than sad, men may appear angry or irritable.
  • Medical conditions. Some medicines and medical conditions may cause symptoms that look like depression. Chronic conditions may make depression worse.

Symptoms of depression are ongoing and affect your day-to-day life. They can include:

  • Feeling sad or "empty"
  • Losing interest in favorite activities
  • Overeating, or not wanting to eat at all
  • Sleeping too much, or not enough
  • Feeling very tired
  • Feeling hopeless, irritable, anxious, or guilty
  • Having aches and pains, headaches, cramps, or digestive problems
  • Having thoughts of death or suicide
  • Changing moods or behaviors
  • Increasing use of alcohol or drugs
  • Isolating from family and friends

If you think you have depression, talk to your health care provider or a mental health provider. To be diagnosed with depression, your provider may use many tools:

  • A medical history will include asking about your symptoms and family history. To be diagnosed with depression, your symptoms must occur most of the day, nearly every day, for at least two weeks. One of the symptoms must be a depressed mood or a loss of interest in most activities.
  • Medical tests may be done to rule out other medical conditions. Certain medicines and medical conditions (such as viruses or thyroid disorders) may cause symptoms like depression.
  • A physical exam to make sure another issue isn't causing your symptoms.
  • A mental health evaluation by your provider or a mental health provider.

Depression may need long-term treatment. Most treatments include medicines and/or psychotherapy (talk therapy):

  • Medicines such as antidepressants may help control your symptoms. You may need to try several medicines to find which works best for you. Medicine may take time to work and can have side effects. Don't stop taking your medicine without first talking with your provider. Contact your provider if you have any concerns about side effects from the medicine.
  • Psychotherapy (talk therapy) under the care of a mental health provider can help you recognize and change troubling emotions, thoughts, and behaviors. This may be done one-on-one or in a group setting. It can give you and your family support, education, skills, and coping strategies.
  • Light therapy has been shown to be effective for seasonal affective disorder (SAD).
  • Other treatments options may be considered if treatment isn't working or if depression is severe. These may include: Electroconvulsive therapy (ECT) is a brain stimulation procedure that uses a mild electric current when you are under general anesthesia. ECT is most often used for severe depression that is not getting better with other treatments.
  • Repetitive transcranial magnetic stimulation (rTMS) is a brain stimulation procedure that uses magnetic waves to relieve depression. It's not as powerful as ECT, but with rTMS, you don't need anesthesia. It also has a low risk of negative effects on your memory and thinking.

Most cases of depression can't be prevented, but healthy lifestyle changes can have long-term benefits for your mental health. These can include:

  • Getting regular exercise
  • Having a consistent sleep schedule
  • Controlling stress

If you, or someone you love is depressed, see your provider or a mental health provider. It's important to get treatment at the earliest sign of a problem.

If you or someone you know has thoughts of hurting themselves or attempting suicide, get help right away. If it is an emergency, dial 911.

It sits within Mental Health and Behavior.

The lead U.S. institute for this subject is the National Institute of Mental Health.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Depression

12,641 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

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Diagnosis and Tests

Treatments and Therapies

Prevention and Risk Factors

Living With

Related Issues

Genetics

Statistics and Research

Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Depression. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Depression, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.