What You Need to Know About Major Depressive Disorder

Other types of depression

What is major depressive disorder?

Many people mistakenly believe that depression is just being sad. Since we all feel down from time to time, it can dilute our understanding of what it actually means to be depressed. In reality, major depression is a common, but serious, mental disorder.

Major depression involves a person feeling low or sad and no longer finding joy in their usual activities which can negatively impact their day-to-day functioning.

While mild major depression can sometimes resolve on its own without treatment, severe major depressive disorder rarely does and almost always requires professional help. While there may be good days and bad days, treatment is generally necessary to help someone recover and prevent further episodes from occurring.

The impacts of major depression can sometimes be hard for people who have not experienced depression to understand. You may need to get work done, but be unable to get out of bed. Finding the willpower for basic self-care, such as eating, bathing, and having moments of fun in your day, can seem impossible.

A person with depression is often aware of the things they could do to help themselves to feel better or address the cause, but they feel they are unable to motivate themselves to do them. This can often make depression worse.

It's easy to see why some people refer to major depressive disorder as ‘crippling depression,’ as it makes the person incapable of performing tasks that a healthy person would be able to do. This is not a medical term, and the word depression itself is often misunderstood or misused.

Severe depression or major depressive disorder is more clinically accurate terms to describe the condition.

If you or someone you know is experiencing signs and symptoms of depression, it is important to seek help from a health professional as soon as possible.

There are a range of available treatments, such as medication, therapy, and hospitalization, as well as making positive lifestyle changes, such as sleep, exercise, diet, and social interactions.

It is important to discuss with your doctor what kind of treatment may be best for you to help you to recover effectively from the major depressive disorder as soon as possible.


Episodes of depression are not just momentary bouts of sadness. They last for most of the day, for days on end. These episodes may occur infrequently in some, yet more frequently in others.

When episodes of depression negatively affect how you live your life, you are likely dealing with severe major depressive disorder rather than a mild major depressive episode.

Symptoms¹ of depression include:

  • Feeling sad or hopeless

  • Fixation on failures, self-blame, or feelings of worthlessness

  • Decreased interest or pleasure in almost all activities

  • Significant weight loss or weight gain, or an increase or decrease in your appetite  

  • Constant lack of energy or motivation

  • Difficulty concentrating

  • Irregular sleep patterns

  • Thoughts of suicide or frequent thoughts of death

For a diagnosis of depression, these symptoms must be present for two weeks and must have resulted in a change in your previous level of functioning.

Sometimes, there will be an event that triggers depression. Problems in your personal life, financial difficulties, a traumatic experience, and other negative events can all bring about depression. However, there may not be an apparent trigger for your depression at all.

Sometimes, people feel persistently down and can't put their finger on why they feel this way. This can be frustrating, but if you find yourself in that situation, it's another sign that you may be dealing with depression.


If you are a parent of a teenager who may be showing signs of depression, they may not be open with you about their feelings. Some warning signs to look out for include:

  • Skipping class or performing poorly in school

  • Drug or alcohol use

  • Decreased social interactions 

  • Loss of interest in activities they once enjoyed

If a teenager in your life is experiencing these issues, it's important to talk to them about it, but keep in mind that they might not be open or honest about their feelings.

This is a time to show compassion and empathy and to be non-judgmental. Pushing the issue could only make the problem worse.

If you are worried about their well-being, you should encourage them to see their GP.

  1. What Is Depression? | American Psychiatric Association


While the exact cause of depression remains unknown, there are a number of factors that can increase a person's risk of becoming depressed.

Major life events

Major life events such as death or loss, toxic relationships, and financial problems can all cause a person to develop depression.

Personality traits

People who are prone to having low self-esteem or are overly pessimistic are more likely to develop depression than those who aren't.

Depression is also common among members of marginalized groups who don't feel supported at home or in the community.

Chemical imbalance

You may have heard about depression being caused by a chemical imbalance in the brain. Neurotransmitters are chemicals in the brain that play a vital role in brain function. Medical professionals suggest that neurotransmitters that are involved in stabilizing the mood may play a role in depression.

Other chemicals in the body, such as hormones, may also contribute to depression if they are out of balance.

Personal history

Having a personal history of depression, or other mental health disorders, can also increase a person’s risk of experiencing depressive episodes in the future.

Family history

Evidence also suggests that major depressive disorder is hereditary. If your parents or other family members have experienced severe depression, there is a higher likelihood that you will too during your lifetime.

Other health conditions

Sometimes, other medical conditions can be a precursor to severe depression. Chronic illness takes a toll on both the physical and mental aspects of your well-being.

In addition, certain medications may cause depression in some people. If you feel your medication is causing you to become depressed, it's important to talk to your doctor, rather than simply not taking the medication. Your doctor will be able to determine whether your medication is causing a problem and can adjust your prescription as necessary.


Diagnosing severe depression can involve a number of steps:


Before a medical professional can assess you, you must decide to seek help. This means that a self-test is the first step to getting a proper diagnosis of major depressive disorder.

When you notice that you're experiencing one or more of the symptoms of severe depression, keep an eye out for further symptoms.

Physical exam

Chronic illness can sometimes be a risk factor for depression. Your doctor will often perform a physical exam as their first step in your diagnosis to rule out any physical cause.

Blood tests

A blood test may help your doctor diagnose any physical cause of your depression.

Psychiatric evaluations

When you go to your mental health professional or general practitioner, you'll likely tell them about the symptoms that lead you to believe you may have depression.

In order to gain a better understanding of these symptoms, and a more complete picture of your mental health, a further evaluation may be performed. These typically include the doctor asking you questions verbally and maybe giving you a questionnaire to fill out. 

The DSM-5 criteria

The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) is a document published by the American Psychiatric Association. It contains a list of criteria for the diagnosis of mental health conditions. Your mental health professional may consult with this document during your visit.


There are a number of treatments¹ available for major depressive disorder and other forms of depression. Depending on the severity of your depression, the intensity of your treatment will vary. There are some treatments, however, that are usually limited to treating more severe forms of depression.


Antidepressants are a broad category of drugs used for treating depression. There are several types of drugs within this category. Each one affects the body in different ways, but all of them function primarily by affecting the brain chemistry that affects mood.

The most common classes of antidepressants include:

  • Selective serotonin reuptake inhibitors (SSRIs)

  • Serotonin-norepinephrine reuptake inhibitors (SNRIs)

  • Tricyclic antidepressants (TCAs)

  • Monoamine oxidase inhibitors (MAOIs)

  • Noradrenaline-serotonin specific antidepressants (NaSSAs)

To find the right medication for you, your doctor may have you try out several prescriptions to see which one works best. This can be a lengthy process, and you'll need to have the patience to find the best medication for your body chemistry.

Sometimes, the doctor can use medical information as a starting point to find the right match. For example, if a family member has had depression, a medication that worked well for them may be tried first.

Antidepressants are not addictive, but they can sometimes cause physical dependence. Don't stop taking your medication abruptly and try not to miss too many doses in a row. If you do, it can cause symptoms similar to withdrawal.

The sudden removal of the medication from your system may also suddenly worsen your depression. If you need to stop taking the medication, your doctor can gradually decrease your dosage to wean you off.


We've all seen TV shows where the character lays on a couch while their psychiatrist asks them how something makes them feel. In the real world, psychotherapy, especially for depression, often comes in the form of cognitive behavioral therapy (CBT).

CBT is the process of helping a person to overcome a set of mental distortions they have. For example, when you're depressed, you may do what is referred to as future predicting. You'll assume something bad is going to happen, or that you won't enjoy something before you've given it a chance. These distortions prevent us from seeing the world clearly and are often worsened by depression.

CBT focuses on helping you to identify when you've made these types of mental distortions and equips you with the skills to prevent them from happening in the future. By giving you the tools you need to overcome these distortions, you can make meaningful changes in your life to reduce depression.

Electroconvulsive therapy

This type of therapy has been around since the 1940s¹ and is typically only used in the most serious cases of major depression. During electroconvulsive therapy, you are put under anesthesia and small amounts of electrical current are passed through certain parts of your brain.

So-called "shock therapy" used to have a poor reputation, but recent advances in both medical technology and in our understanding of how the brain works have transformed ECT into a safe and effective treatment for serious cases of major depression.

Hospital or in-patient treatment

Sometimes, the effects of depression on a person's life are so severe that they need to be hospitalized. If you are considering suicide or harming someone else, the best solution may be for you to stay in the hospital to receive the treatment you need.

If you have already attempted suicide, hospitalization will almost certainly be recommended to ensure your safety and that you receive treatment.

Even when there are no risk concerns, hospital admission may still be recommended. This may be where your depression is so severe that you have become unable to care for yourself, in which case a hospital will provide you with a safe environment for you to recover.

Historically, the media has portrayed inpatient units as scary, cold, and uninviting places. In reality, medical professionals understand that patients recover best in a comfortable supportive environment. The mental health wing of a hospital will therefore often feel more like a college dorm² than a hospital.

A schedule will be provided for eating, treatment, and recreation. The average stay is ten days for adults and eight days for children and teenagers.

  1. What Is Depression? | American Psychiatric Association

  2. What to Expect If You Need Inpatient Hospitalization | Psychology Today


While there's no way to prevent depression, there are some lifestyle changes you can make to help minimize your risk and support your recovery.

Lifestyle changes can be a form of treatment on their own, as they minimize the severity of your depression and help reduce the frequency of episodes.


Exercise is well-known for its mood-elevating endorphins, both in terms of the initial pump after a workout and the long-term benefits of a regular exercise routine.

Mindfulness practices

Mindfulness practices like meditation, yoga, or tai chi can also aid in elevating your mood and fighting the effects of depression. Practitioners have made these claims for centuries, but it is also backed up by science¹, particularly for yoga and mindfulness meditation.

Getting enough sleep

Getting enough sleep is also vital for mood stability. Not sleeping enough makes you tired and irritable, and is especially harmful to someone who has depression. The lethargy that comes from depression will also be worsened if you haven't had enough rest the night before.

Many people who are depressed turn to alcohol or other recreational drugs to make themselves feel better in the short term. This should always be avoided. While substances can feel like they are giving you a temporary fix, they can lead to dependence and make it difficult for you to function on top of the effects of depression.


While depression may make you feel as though no one understands you and what you are going through, you are not alone. Millions of people deal with major depression, making it one of the most common mental health disorders.


Statistics¹ from the National Institute of Mental Health (NIMH) show just how prevalent the condition is in the US:

  • 7.8% of all adults experienced at least one major depressive episode in 2019 (over 19 million people).

  • The gender breakdown is 9.6% women and 6% men.

  • Over 13% of people with mixed-race backgrounds reported having at least one major depressive episode. 

  • Depressive episodes were most prevalent, at over 15%, among the 18-25 demographic.

Although the data is slightly older, there are some interesting breakdowns from the CDC from 2013-2016 which focuses on the prevalence of depression among adults aged 20 and older:

  • Non-Hispanic Asians had the lowest prevalence of depression among the population group.

  • 15.8% of adults living below the federal poverty level had depression, compared to just 3.5% who were making four times or more than the average income at the poverty level. 

  • 50% of adults with depression reported some difficulties at work, home, or social activities. 30% reported moderate or extreme difficulty. Although rates of depression are different between men and women, the percentage reporting the difficulties was the same across genders.

The National Alliance on Mental Illness (NAMI) has further statistics² on the effects of major depression:

  • The chance of developing a cardiovascular or metabolic disease is 40% higher in those with depression than those in the general population.

  • When high school students have significant depression, they are more than twice as likely to drop out of school than their peers. 

  • Depression and anxiety disorders are a leading cause of disability worldwide and cost the global economy $1 trillion every year in lost productivity.

  1. Major Depression | NIH: National Institute of Mental Health

  2. Mental Health By the Numbers | National Alliance on Mental Illness

Clinical trials for major depressive disorder

Actively recruiting
Major Depressive Disorder Study
Actively recruiting
The Candesartan Adjunctive Major Depression Trial - CADET: A double-blind, randomised, placebo-controlled trial
Actively recruiting
XEN1101 for Major Depressive Disorder