UNDERSTANDING MAJOR 

DEPRESSIVE DISORDER

WHAT IS MAJOR DEPRESSIVE DISORDER?

SAMHSA’s mission is to reduce the impact of substance abuse and mental illness on America’s communities. 

1-877-SAMHSA-7 (1-877-726-4727) • 1-800-487-4889 (TDD) • www.samhsa.gov Substance Abuse and Mental Health

Services Administration

The subject in this photo is a model for illustrative purposes only.

Major depressive disorder (also known as major 

depression) is one of the most common mental 

disorders in the United States. It can seriously 

impact every aspect of a person’s life—affecting 

how they feel, think, and handle everyday activities. 

Major depression can happen at any age but often 

begins in adulthood. 

The exact causes of major depression are unknown, 

but some risk factors include a family history of 

depression and significant life changes such as 

trauma, stress, or death of a loved one. Major 

depression is also linked to other serious medical 

illnesses, such as diabetes, cancer, heart disease, 

and Parkinson’s disease. 

COMMON SIGNS & SYMPTOMS OF MAJOR DEPRESSIVE DISORDER

Some of these signs and symptoms must be present for at 

least two weeks to be diagnosed with major depressive 

disorder. Anyone who has questions should consult their doctor. 

• Long-term feelings of sadness, hopelessness, 

pessimism, emptiness

• Anxiety, irritability, restlessness

• Feelings of guilt or worthlessness

• Loss of interest or joy in normal hobbies and activities

• Fatigue, lack of energy

• Changes in appetite that lead to weight loss or weight gain 

• Moving, talking, or thinking more slowly

• Trouble concentrating, remembering, or making decisions

• Sleep issues such as insomnia, waking up very early, or 

sleeping too much 

• Unexplained aches and pains, such as headaches or 

digestive problems 

• Thoughts of death or suicide, or suicide attempts The subject in this photo is a model for illustrative purposes only.
TYPES OF MAJOR DEPRESSION

THERE ARE SEVERAL TYPES OF DISORDERS THAT FALL UNDER MAJOR DEPRESSIVE DISORDERS:

Postpartum Depression 

affects women after 

childbirth and causes 

extreme anxiety and 

sadness, making it 

difficult for mothers to 

care for themselves and/

or their babies. 

Psychotic Depression 

is a form of depression 

with psychosis that may 

include delusions and/ 

or hallucinations where 

the person is both 

depressed and out of 

touch with reality. 

Seasonal Affective Disorder 

is a mood disorder directly 

caused by the time of the 

year, most often occurring 

in the winter months 

when sunlight is not as 

readily available.

Melancholic Depression

is a form of depression 

in which people exhibit a 

complete loss of pleasure 

in all or almost everything.

TREATMENT

Even the most severe cases of depression can be 

treated with medication, therapy, or both. And the 

earlier a person begins treatment, the more effective 

it is. Treatment for major depression, just like 

hypertension, diabetes, and heart disease, requires 

long-term management of symptoms. 

• Medication: Antidepressant medicines 

may help improve the way a person’s brain 

controls mood or stress and reduce symptoms. 

Antidepressants usually take two to four weeks 

to take effect. Sleep, appetite, and problems 

concentrating often improve before a noticeable 

mood shift, so it is important to give medication 

a chance to work. 

• Therapy: Talking to a mental health professional 

is effective in helping people identify triggers, 

create positive behaviors, manage stress, set 

goals, and stick to a treatment plan. 

The subject in this photo is a model for illustrative purposes only.

NEED HELP OR MORE INFORMATION?

If you or someone you know has major depressive disorder, these resources can help. Visit SAMHSA’s Early 

Serious Mental Treatment Locator and Behavioral Health Treatment Locator at SAMHSA.gov. Or, call 

SAMHSA’s National Helpline at 1-800-662-HELP (4357) or 1-800-487-4889 (TDD).

Learn more at SAMHSA.gov/Serious-Mental-Illness

SAMHSA’s mission is to reduce the impact of substance abuse and mental illness on America’s communities. 

1-877-SAMHSA-7 (1-877-726-4727) • 1-800-487-4889 (TDD) • www.samhsa.gov Substance Abuse and Mental Health

Services Administration