Depression: Types, Causes, Symptoms and Treatment

By Danielle Boland

You can feel sad or have no energy for a lot of different reasons. These feelings are often a normal reaction to the ups and downs of life, but they can also be a sign that depression may be developing. Knowing the signs, symptoms, risk factors and treatment options for depression can help you know what to look for and how to address it. 

What Is Depression?

Depression is a mood disorder that can have a significant impact on someone’s mental health. There are different forms of depression, such as postpartum depression, seasonal affective disorder (SAD) and persistent depressive disorder. All of these types of depression cause symptoms that affect the way someone thinks, feels, acts and interacts. In order to be diagnosed with clinical depression, someone has to experience symptoms continuously for two weeks. 

According to NAMI, 21 million adults in the United States experienced a depressive episode in 2020. This spanned across all genders, ages and ethnicities. 

How Long Does Depression Last?

There is no exact length of time that depression lasts. Depression affects everyone differently, and how long depression lasts can vary widely from person to person. The chronic form of depression is called dysthymia. Dysthymia is a less severe type of depression but is long-lasting. People may suffer from dysthymia for many years. Major depressive disorder is another type of depression that is more severe and can last anywhere from a few days or months to several years. 

If you think you may have depression or be at risk for it, you can track how you feel to see if you are experiencing frequent depressive symptoms. 

Types of Depression

Depression can occur at any time in a person’s life and for many different reasons. There are different types of depression, and each one is diagnosed based on the severity, length and reason for the depressive symptoms. It is important to know the different types of depression because they may require different types of treatment or intervention. 

Most Common Types Of Depression

Types of depression can vary widely in terms of symptoms, length and causes. Some types of depression have more consistent or intense symptoms, while others are circumstantial and relate to a specific event in someone’s life. The most common types of depression include: 

  • Major depression
  • Bipolar disorder
  • Persistent depressive disorder (dysthymia) 
  • Seasonal affective disorder
  • Postpartum disorder

Other Types of Depression

In addition to the most common types of depression, there is another subset that includes more specific types of depression. Some forms of depression affect only women, occur during specific times or happen after specific events. Other mental health concerns and symptoms like hallucinations or delusions can also accompany depressive symptoms. Subtypes of depression include:

  • Psychotic depression
  • Premenstrual dysphoric disorder (PMDD)
  • Disruptive mood dysregulation disorder (DMDD)
  • Situational depression
  • Atypical depression

What Causes Depression?

There is no singular cause for depression, and each person with depression can have a different reason for their depressive symptoms. Still, specific life changes and certain risk factors can easily contribute to the development of depression. The death of a loved one, pregnancy or birth, the loss of a job, the change of seasons and a family history of depression can all cause someone to develop depression. It is important to know the risk factors for depression to know if you are at a higher risk of becoming depressed. 

Risk Factors for Depression

Common risk factors for depression include: 

  • Genetics
  • Biological factors
  • Other mental health disorders
  • Drug or alcohol abuse
  • Trauma
  • Life changes
  • Chronic medical conditions

Depression Symptoms

Depression has many different symptoms that can alter a person’s day-to-day ability to function. To be diagnosed with depression, the symptoms have to last for two weeks or more. Individual symptoms and their severity can vary widely from one person to another. Common symptoms include:

  • Sleep disruption
  • Changes in appetite
  • Inability to concentrate
  • Loss of interest in normal activities
  • Feeling constantly tired
  • Feeling hopeless
  • Potential suicidal thoughts
  • Physical aches and pains
  • Low self-esteem

How Is Depression Diagnosed?

In order to be diagnosed with depression, someone has to be experiencing depressive symptoms for at least two consecutive weeks. The main symptom doctors look for during diagnosis is a depressed or sad mood or withdrawal from normally enjoyed activities.  Doctors will perform a mental health assessment and gauge how long someone has been experiencing their symptoms, when they first started, how long the feelings last and how often the depressive episodes occur. The doctor will normally ask about overall physical health in addition to mental health, as certain physical illnesses can cause symptoms of depression. Performing lab tests, physical exams and other diagnostic tests can also help determine what is causing someone to feel depressed.

Depression Test

Knowing what symptoms someone is experiencing can help determine what type of treatment may be needed. There are various diagnostic tools used to help find out if someone is suffering from depression or something else. According to the American Psychological Association, there are a few tools that are reliable in helping to diagnose depression. There are tests to evaluate depression before, during and after treatment as well. These can include:

  • Beck Depression Inventory (BDI)
  • Beck Hopelessness Scale
  • Patient Health Questionnaire (PHQ-9)

Depression Treatment

Although being diagnosed with depression can be scary, it is also treatable. There are many different forms of treatment for someone suffering from depression, including psychotherapy, medication treatment and alternative treatment options such as yoga, meditation and nutrition therapies. 

Counseling

Psychotherapy, or talk therapy, can help someone create healthy coping mechanisms to relieve the symptoms of their depression. Examples of evidence-based therapies specific to treating depression include:

  • Cognitive-behavioral therapy (CBT)
  • Interpersonal therapy (IPT)
  • Problem-solving therapy

If you are looking for an easy way to connect with support on your own terms, the Nobu app is a great option. The Nobu app is free to use and has plenty of helpful resources, including mindfulness tools, mental health lessons, journaling and goal-tracking. You can also use the app to work with a licensed therapist for an additional cost. 

Medication for Depression

Medication therapy can be a useful way to help treat depression symptoms in some people. There are different types of medications, such as antidepressants, mood stabilizers and antipsychotics, that all have been found to help manage depression. 

SSRI and SNRIs

Selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs) are both antidepressants. SSRIs increase serotonin levels, and SNRIs increase serotonin and norepinephrine. Common SSRIs are:

  • Zoloft
  • Prozac
  • Lexapro 
  • Celexa

Common SNRIs include:

  • Cymbalta
  • Effexor

Tricyclic and Tetracyclic Antidepressants (TCAs)

TCAs help increase the level of norepinephrine and serotonin while also reducing acetylcholine. Balancing these neurotransmitters in the brain can help alleviate depression. Common TCAs include:

  • Elavil
  • Asendin

Monoamine Oxidase Inhibitors (MAOIs)

MAOIs are used less often than other antidepressants, as they work differently and carry additional risks. They treat different forms of depression and other disorders, such as panic disorder, social phobia and depression with atypical features. 

Common MAOIs include:

  • Emsam (skin patch)
  • Marplan
  • Nardil

Electroconvulsive Therapy (ECT)

Electroconvulsive therapy (ECT) involves transmitting short electrical impulses into the brain. ECT does cause some side effects, including memory loss. A study conducted in the United Kingdom found that ECT is effective in patients with major depressive disorder who don’t respond to other forms of treatment. Out of those surveyed, more than half went into remission after ECT.

Lifestyle Changes

In addition to medical interventions like medication and psychotherapy, making changes in your daily routine can help to combat depression. Helpful life changes a person can make to reduce their depression symptoms include:

  • Exercise
  • Meditation
  • Improved nutrition

If you or someone you love is suffering from depression, help is available. The free-to-use Nobu app can supplement your mental health treatment or provide you with helpful ways to reduce depression’s impact on your life. You can even connect with a licensed mental health professional for an additional fee. Download the Nobu app today, and see how it can help you live a healthier, happier life.

jonathan strum headshot

Edited by – Jonathan Strum

Jonathan Strum graduated from the University of Nebraska Omaha with a Bachelor’s in Communication in 2017 and has been writing professionally ever since. He has written, edited and published content for health care professionals, educators, real estate agents, lawyers and high-level university faculty… Read more.

Written by – Danielle Boland

Danielle is a licensed clinical social worker, currently living and practicing in central Connecticut. Danielle graduated from Columbia University in 2012 with a Masters of Social Work, and always had the goal of opening her own private practice. She specializes in women’s issues, maternal health and postpartum mental health. Danielle is passionate about empowering people of all ages and hopes to use her writing skills to provide more resources for those looking to improve their mental health… Read more.

dr angela phillips

Medically Reviewed by – Dr. Angela Phillips

Angela is a licensed therapist and clinical researcher, and has worked in public, private, government, and not-for-profit organizations, across clinical and research-oriented roles. Angela’s clinical and research experience has included suicide prevention, cognitive behavioral… Read more.