Depression: Types, Symptoms, Causes & Treatment

If someone asked you, “What is depression,” right off the bat you may have mental images of someone who’s perpetually sad, struggles to get out of bed and believes there’s no hope.

While this can sometimes be true, depending on the person, this mental health condition (technically known as major depressive disorder) can actually present in many different ways. There are several different types of depression, as well as different symptoms and treatments. All of these factors lead some to conclude that depression is a disease.

Below, we’ve explained the different types of depression, common symptoms of this mood disorder and what causes depression, as well as treatment options and how healthcare providers diagnose depression.

Types of Depression

The world of mental health conditions is vast, and there are several different forms of depression. Knowing about the different depression types can be useful — not only do symptoms differ between depression types, but some treatment options may be best for your form of depression.

Before we dive too far into all the depression types, it might be a good first step to answer the question of what depression is. According to the National Institute of Health (NIH), depression is a common but serious mood disorder that affects how you think and feel. Depression is also known as major depressive disorder, major depression or clinical depression (but we’ll mostly refer to it as depression).

Depression is so common that the National Institute of Mental Health found that approximately 21.0 million adults in the U.S. had at least one major depressive episode (a down or hopeless period) in 2020 — roughly 8.4 percent of all U.S. adults.

The most common types of depression include:

• Major depressive disorder (MDD). While feeling unhappy or down from time to time is normal, a persistent, negative mood that interferes with your daily life and results in a loss of interest in certain activities could be a sign of a depressive episode or major depressive disorder. For a diagnosis of major depressive disorder, symptoms must be present for at least two weeks.

• Persistent depressive disorder. Also known as dysthymia or chronic major depression, persistent depressive disorder is less severe depression that lasts for two years or more. Someone with persistent depressive disorder may feel like they’re constantly going in and out of depression. The name of this disorder has changed over the years, and persistent depressive disorder was used for the first time in the most recent DSM-5 (a reference manual for mental health conditions).

• Seasonal affective disorder (SAD). A mood disorder that occurs seasonally, most often in the winter although summer seasonal depression is possible as well. Those with seasonal affective disorder may develop depression on a recurring seasonal basis but feel mentally healthy during other periods of the year. Women and young adults commonly develop seasonal depression symptoms.

• Psychotic depression. A severe depression type, psychotic depression is a depression with signs of psychosis, such as delusions or hallucinations.

• Bipolar disorder. Once referred to as manic depression, bipolar disorder is a mental illness where people experience periods of low moods that match the symptoms of depression alternating with periods of high or euphoric moods (mania).

• Peripartum depression. Formerly known as postpartum depression, peripartum depression is when depressive episodes occur during pregnancy or within four weeks postpartum (after giving birth) — although some say peripartum depression can be diagnosed up to one year postpartum. While feeling the “baby blues” after giving birth is normal, symptoms that persist for several weeks may indicate peripartum depression.

• Premenstrual dysphoric disorder (PMDD). Another type of depression unique to women, premenstrual dysphoric disorder is a severe form of premenstrual syndrome (PMS) that can cause depression near ovulation.

• Atypical depression. Some people experience common depression symptoms but may experience an improved mood after certain positive events. This condition is called atypical depression.

• Adjustment disorder. Technically, adjustment disorder isn’t a type of depression, but some types of adjustment disorder — emotional and behavioral reactions to stressful events or changes — can involve depressive symptoms. This condition is less severe and generally lasts for less time than major depressive disorder and may occur after a stressful event such as a death, divorce or separation. It may also be referred to as situational depression, although this isn’t a technical term in psychiatry.

Other types of depressive disorders aren’t classified in the DSM-5 but can still affect people. Hidden depression, for example, is essentially the same as major depressive disorder with one exception — people with hidden depression work hard to conceal their symptoms.

Symptoms of Depression

Like we mentioned, depression doesn’t just look like a sad person who can’t get out of bed — just as there are several types of depression, there are also different symptoms.

These symptoms will vary depending on the individual and the specific type of depression they have — some people may experience more physical symptoms while others find their mood affected more. You’ll see below that some of these symptoms are even contradictory (e.g., weight gain and weight loss) because each person will present with their own unique set of symptoms.

There are some common symptoms of depression though, which we’ve described below to save you from having to obsessively search for symptoms of depression episodes:

• Persistent feelings of sadness, tearfulness, anxiety, hopelessness and/or an “empty” mood

• A loss of interest in activities that are normally pleasurable, such as sex and hobbies

• Irritability and anger, or frustrated outbursts over minor issues

• Reduced appetite and weight loss

• Increased appetite, food cravings and weight gain

• Lack of energy, or fatigue

• Insomnia, including difficulty falling asleep and early morning awakening

• Oversleeping and struggling to wake up

• Feelings of restlessness, anxiety and agitation

• Physical pain and other physical symptoms, including headaches and digestive problems

• Difficulty focusing, making decisions and recalling information (nicknamed brain fog depression)

• Noticeably slower speech and movement

• Recurrent thoughts of death, suicidal thoughts and suicide attempts

You can learn more about signs of depression in our in-depth article.

What Causes Depression?

While it would be amazing to pinpoint an exact reason that some people get depressed, there can be numerous possible causes. Depression is a complex combination of factors that researchers are still discovering, but the causes below have evidence behind them.

• Changes in brain chemistry. Depression may be caused by changes in certain brain chemicals called neurotransmitters, which are responsible for transmitting information between nerve cells. Although there’s some debate as to which neurotransmitters play major roles in depression, research indicates that serotonin — a hormone that’s often linked to mood — may have a significant role in the development of depression. And beyond neurotransmitters, depression affects the brain in several ways.

• Hormones. Changes in the levels of certain hormones may affect mood and contribute to depression. Events that can affect hormone production include the use of certain types of medication, thyroid issues and, for women, pregnancy, childbirth and menopause.

• Genetic factors. Depression occurs more frequently in people with family members who have also had depression. Although research is still ongoing, genetic factors may play a role in depression and other mood disorders.

Depression Risk Factors

Some people may have a higher risk of developing depression than others. The factors that can increase your risk of depression include:

• Family history and genetics. Your genetics may play a role in your risk of developing depression.

• Environmental factors. Environmental factors, such as a stressful work environment, being exposed to abuse or living in poverty, may affect your risk of developing depression.

• Personality. Depression may be more common in people with certain personality traits, such as low self-esteem or a  low resilience to stress. Pessimistic people may also be more likely to develop depression.

• Physical health. Depression is closely linked to certain medical conditions, such as cardiovascular disease.

Depression Treatment Options

The good news is that this mood disorder is treatable. There is a range of safe, effective treatments available for depression ranging from mild to severe. Many are most effective when they’re started early, making it important to talk to a healthcare provider if you feel depressed.

Common depression treatment options include medication, psychotherapy and a range of other therapies.

Depression Medications

Major depressive disorder is often treated with antidepressant medications. Antidepressants are thought to work by changing the levels of certain neurotransmitters in your brain that control mood, appetite, sleep habits and other behaviors.

There are several different types of antidepressants used to treat all different types of depression:

• Selective serotonin reuptake inhibitors (SSRIs). Selective serotonin reuptake inhibitors are generally the first line of medication for depression due to their effectiveness and the fact that they cause fewer side effects than other antidepressants. Some common SSRIs include escitalopram (Lexapro®), fluoxetine (Prozac®), sertraline (Zoloft®), paroxetine (Paxil®) and citalopram (Celexa). SSRIs are FDA-approved to treat several types of depression, such as major depressive disorder, bipolar depression, premenstrual dysphoric disorder and treatment-resistant depression, as well as more mental health conditions.

• Serotonin-norepinephrine reuptake inhibitors (SNRIs). SNRIs are a relatively newer class of antidepressants used to treat depression and certain anxiety disorders. Some common SNRIs are venlafaxine (Effexor®) and duloxetine (Cymbalta®).

• Norepinephrine-dopamine reuptake inhibitor (NDRI). Certain antidepressants are referred to as atypical, as they don’t fit into specific categories. One common atypical antidepressant is bupropion (Wellbutrin XL®).

Antidepressants are used to relieve depression symptoms, and while they’re effective for moderate and severe depression, they may not be as helpful in treating mild depression.

Psychotherapy

Another effective treatment for depressive disorders is psychotherapy, also known as talk therapy. Just like antidepressants, there are several different types of therapy used to treat depression, including interpersonal therapy and cognitive behavioral therapy (CBT).

As part of psychotherapy — whether in-person or in online therapy — you’ll talk with a licensed mental health professional to identify and overcome the factors that may be contributing to your depression. You may also learn how to identify thought processes or beliefs that contribute to your symptoms, how to manage difficulties and more.

Also similar to antidepressants, talk therapy has been found to be effective for those with severe depression.

Other Treatments for Depression

Depending on the type of depression you have, your symptoms and your response to treatment, your healthcare provider may recommend a different form of treatment for depression.

Brain stimulation therapies such as electroconvulsive therapy (ECT) may provide relief from depression, including severe depression, when other treatments are ineffective or insufficient.

People with severe depression may also require hospital treatment, especially if they are at risk of self-harm, unable to take care of themselves or affected by extremely severe depressive symptoms.

Home Remedies and Lifestyle Changes

While depression isn’t a condition that can be fully treated using home remedies, making changes to your habits and lifestyle, in combination with proven treatments for depression, may help you deal with depression and work towards recovery.

For example, if you struggle with seasonal affective disorder in the winter when there’s less sunlight, using sunlight lamps for depression may help improve your mood.

You can also ask loved ones for help and use self-care techniques and other healthy coping mechanisms to manage depressive symptoms.

While there’s unfortunately no straightforward answer to the question of whether there’s a cure for depression, making certain lifestyle changes and using other tips for living with depression may help relieve certain symptoms. 

Talk to a Healthcare Professional About Depression

Depression isn’t just staying curled up on the couch, feeling down and hopeless about life (although it can look like that). There are several different types of depression and a variety of potential depression symptoms. Here’s what you need to remember:

• Some common depressive disorders include major depressive disorder, seasonal affective disorder, persistent depressive disorder, bipolar disorder, peripartum depression, premenstrual dysphoric disorder and more.

• The cause of depression is unknown, but there is evidence that a few factors — changes in brain chemistry, hormones and genetic factors — may be possible causes.

• There can be both mental and physical symptoms of depression that vary in severity, as well as by person and disorder, but common symptoms include feeling hopeless or empty, loss of interest in typical activities, weight changes, trouble with sleep and more.

• Just as there are different forms of depression, there are also different treatment options. Antidepressant medications and psychotherapy are the most common treatments for several depressive disorders.

Dealing with depression is certainly draining, mentally and physically. However, this mental health condition is highly treatable. Mental health services can give you even more information on depressive disorders, while a licensed mental health professional or healthcare provider can help you find a treatment plan through online psychiatry

Or if you need immediate help, these depression hotline numbers can support you as soon as possible.