Major Depressive Disorder (MDD)

Major Depressive Disorder site

Verified by World Mental Healthcare Association

Major depressive disorder (MDD) is a mood disorder characterized by feelings of sadness, loss of interest, and worthlessness. It can significantly affect our health and our lives if left untreated.

What Is Major Depressive Disorder?

Major depressive disorder is a psychological condition 1 that not only affects our thinking, mood, and behavior, but also our physical wellbeing. Other than a constant feeling of sadness, those affected may experience –

  • Low energy
  • Low self-esteem
  • Aches and pains without any probable reason
  • Loss of interest in activities they used to enjoy earlier

It can also affect their ability to study, work, eat, sleep, and socialize. In severe cases, it can lead to self-harm and suicide. According to the World Health Organization 2, it is also the primary reason for disability across the globe.

Thankfully, the major depressive disorder has been thoroughly studied and understood by mental health professionals and is considered a treatable condition. People with this disorder can recover fully with the help of therapy and medication. Unfortunately, due to stigma, most people suffering from MDD do not seek treatment to cope with their symptoms.

What is the difference between MDD and a depressive episode?

A single episode of depression lasts about two weeks. However, Major Depressive Disorder consists of multiple episodes of depression separated by at least two months. Unlike mood fluctuations, MDD can require months or even years of treatment. MDD is also known as clinical depression, unipolar depression, and major depression.

Symptoms Of Major Depression

Symptoms Of Major Depression

A person suffering from the major depressive disorder will experience multiple depressive episodes consisting mainly of the following signs and symptoms based on the DSM-5 3

A. Psychological symptoms

  1. Persistent sadness
  2. Low mood
  3. Excessive overthinking
  4. Stress, anxiety, and frustration
  5. Feelings of hopelessness and worthlessness
  6. Irritability and agitation
  7. Feelings of guilt
  8. Pessimism and helplessness
  9. Loss of interest in pleasurable activities
  10. Difficulty in concentrating and making decisions
  11. Memory problems or difficulty in remembering details
  12. Angry outbursts over small issues
  13. Poor performance at work or school
  14. Drug and alcohol abuse
  15. Suicidal thoughts and tendencies

Read More About Stress Here

B. Physiological symptoms

  1. Reduced energy, constant exhaustion, or fatigue
  2. Lethargy
  3. Feelings of restlessness
  4. Slowed thinking, talking, or body movements
  5. Difficulty in sleeping, or excessive sleeping
  6. Changes in appetite
  7. Weight loss or gain
  8. Digestive problems
  9. Headache disorders
  10. Body aches or pains due to unknown reasons
  11. Injuries due to self-harm

Some individuals may also experience fluctuations in motor abilities, have psychotic episodes, and show signs of mania. However, not every person suffering from major depressive disorder will experience all of its symptoms.

For instance, major depressive disorder in children 4 can manifest as lost interest in activities, sadness and extreme introversion, and hyperactivity.

Case Example

Consider Riya, a 32 year old Marketing Executive who suddenly started being absent from work very frequently and stopped attending social events. This was very uncharacteristic of her, as she had always been an extrovert and a sincere performer.

A few weeks earlier, a very close friend of Riya’s had passed away. This had come as a shock to Riya, who found it hard to come to terms with the news. Since then, she was unable to eat, stating a constant pain in her chest that was making it hard for her to swallow.

For most of the time that she was at home, Riya was sleeping. Despite that, she felt tired all the time. She was barely speaking with her family and friends, and was spending most of her time by herself.

A concerned coworker recommended Riya to visit a therapist. Riya however was reluctant to the idea, saying, “It’s all pointless, anyway. Nothing matters anymore.” Some weeks later, she started going to work regularly again and was able to eat better. She also felt less tired. Gradually, she started going out with her friends again.

Three months later, Riya’s absenteeism resumed. She was again isolating herself from her loved ones and beginning to spend most of her time in her room. She decided to consult the therapist this time, who eventually diagnosed her with Major Depressive Disorder.


People suffering from MDD are affected in a variety of ways. Apart from low mood, they can also –

  • Experience Anxiety
  • Suffer from Insomnia
  • Experience psychotic symptoms such as hallucinations and delusions.
  • Worry excessively about their physical health.
  • Have difficulty functioning effectively at school or work
  • Have frequent conflicts in interpersonal relationships
  • Be vulnerable to substance abuse and addiction
  • Have low sexual drive among other things

Major depression is also believed to affect and alter 5 regions of the human brain which help regulate moods. In people with depression, nerve cells in specific areas of the brain function ineffectively, which affects communication between nerve circuits.

People suffering from this disorder are prone to developing certain comorbid disorders 6, that can further increase the likelihood of suicidal thoughts and behavior in sufferers. Such disorders include:

  • Obsessive-compulsive disorder
  • Social anxiety disorder
  • Panic disorders

Read More About Panic Disorder Here

Causes Of MDD

Causes Of MDD

Medical professionals are yet to fully understand the specific causes of major depressive disorder. However, research 7 suggests that this mental condition is likely caused by a combination of factors, like:

1. Genetic factors

According to the American Psychiatric Association (APA), depression can be an inherited condition.

  • If you have a family member who suffers from depression, then it is highly likely that you will develop major depression sometime in your life 8.
  • A person is twice more likely to suffer from major depression if he/she has a grandparent or a parent with depression 9
  • If one identical twin suffers from clinical depression, the other has a 70% chance of having the disorder. 10.

2. Biological factors

Major depressive disorder is a serious medical illness linked to several brain regions and circuits 11. Thus, disruptions in brain chemistry and brain function can be a notable cause of MDD 12, such as:

  • Dysregulated neurotransmitters, like norepinephrine, dopamine, and serotonin, that influence our emotions and put our feelings of happiness and joy out of balance
  • Hormonal changes due to thyroid problems, childbirth, menopause, and different health disorders.
  • Different physical illnesses—like cardiovascular diseases (CVD), Parkinson’s disease, and cancer.

3. Psychosocial factors

According to the APA, major depressive disorder can occur due to several psychosocial factors, such as:

  • Constant exposure to violence, abuse, trauma, neglect, or poverty.
  • Loss of a loved one 13
  • Unemployment
  • Relationship problems
  • Financial issues
  • Serious illness
  • Childhood trauma 14
  • History of substance abuse in the family

Apart from these, there may be various other factors that can contribute to the development of MDD in an individual. These include:

  • Lifestyle changes
  • Social isolation
  • Separation or abandonment
  • Personal conflicts in relationships
  • Changes in appetite or poor nutrition
  • Circadian rhythm disturbances
  • Alcohol or drug abuse
  • Excessive stress
  • Personality issues like low self-esteem and pessimism
  • Major stressful life events


The diagnosis of major depressive disorder is usually carried out by a mental health professional after analyzing the history of the patient’s symptoms and how they make them feel, along with their personal, social and family history.

Currently, there is no medical test for major depressive disorder. However, certain tests may be recommended for other medical conditions, like thyroid, to gain a better understanding of the cause of the symptoms. A psychologist usually carries out certain psychometric tests for depression such as:

  • Hamilton Rating Scale for Depression (HAM-D)
  • Beck’s Depression Inventory (BDI)

As per the DSM-5 3 criteria for major depressive disorder:

  • A person must have at least 5 major symptoms of depression
  • They should have experienced at least two depressive episodes separated by 2 months
  • They must experience significant difficulty functioning in their day-to-day life due to the symptoms


According to the WHO 15, over 264 million individuals of all ages suffer from major depressive disorder across the world, with more women affected than men.

Moreover, MDD happens to have an average lifetime prevalence of about 12% 7. Research 16 also shows that lifetime rates in developed nations are around 15%, which is relatively higher than that of developing countries at 11%. However, the short-term prevalence of major depressive disorder symptoms is around 7% with significant differences across age groups.

Major depressive disorder is more common in people without close interpersonal relationships, and who are divorced or separated, or widowed. However, there aren’t significant differences across socioeconomic statuses or racial or ethnic groups 16.

Treatment For MDD

Unfortunately, many people suffering from major depression do not seek any treatment, although it is one of the most treatable mental disorders. According to a 2018 study 17, only one in five people in the richest countries seek treatment for depression, whereas only one in 27 people in the poorest countries seek help.

This is perhaps due to the stigma attached to mental illnesses and the regressive attitude of our society towards depression. Moreover, the patient’s ability to recognize the condition and seek help may be distorted due to the limited knowledge surrounding clinical depression and the debilitating nature of the mental illness.

Hence, friends and family play a crucial role when it comes to recognizing the major depressive disorder symptoms and encouraging individuals to seek treatment. According to emerging research 18, around 80-90% of patients respond well to treatment.

The treatment for major depressive disorder usually involves medication or therapy, or a combination of both.

1. Medication

Different types of antidepressants may be recommended by a mental health professional depending on the individual and the severity of your symptoms. These include:

  • Atypical antidepressants 19
  • Monoamine oxidase inhibitors (MAOIs 20)
  • Selective serotonin reuptake inhibitors (SSRIs) 21
  • Selective serotonin and norepinephrine reuptake inhibitors (SNRIs) 22
  • Tricyclic antidepressants 23

Antidepressants can substantially help in treating moderate to severe major depressive disorder. Each type of medicine focuses on a specific neurotransmitter, influencing how your brain processes specific chemicals which regulate stress and mood.

In case you notice any severe side effects, you should contact your healthcare provider immediately. It is recommended that you do not stop the medication on your own as it might result in a relapse. You should only take antidepressants if you have been prescribed by your psychiatrist, as per their instructions.

Read More About Antidepressants Here

2. Psychotherapy

Psychotherapy includes therapy techniques like

A combination of psychotherapy and medications can enable a person with major depression to recover fully. In fact, CBT has proven to be highly effective in treating depression 24. However, the duration of major depressive disorder treatment depends on the severity of the condition, lasting from a few weeks to a few months.

Psychotherapy can help an individual to:

  • Cope with emotional problems
  • Accept and adjust to stress or a mental crisis
  • Remove negative thoughts and behaviors
  • Reinforce positive thoughts and behaviors
  • Understand how depression affects their mood
  • Improve communication and relationships
  • Devise effective self-help strategies
  • Cope better with problems and challenges
  • Boost self-esteem
  • Regain control in their life

Read More About Psychotherapy Here

Self Help Tips

Here are some self-help tools that can help you cope with major depressive disorder:

  • Educating yourself about the disorder
  • Lifestyle changes (eg; a proper sleep schedule, diet, avoiding substance use, etc.) 25
  • Physical exercise 26
  • Yoga 27
  • Breathing exercises 28
  • Meditation 29
  • Mindfulness 30
  • Joining social support groups
  • Communicating with friends and family

Read More About Mindfulness Here


Major depression is a serious mental illness that can be effectively treated with timely and prompt diagnosis and treatment. If you or someone you know is suffering from MDD, then the first thing to do is visit a primary care physician or mental health professional.

But it is also important to stick with the treatment program to improve the patient’s perspective in life and enable his/her full recovery to live a happier and better life.

At A Glance

  1. Major depressive disorder (MDD), generally known as depression, is a mood disorder characterized by chronic sadness, despair, and even suicidal thoughts.
  2. MDD affects our thinking, mood, behavior, and physical wellbeing.
  3. It can be of various types.
  4. It alters regions of the human brain that regulate mood.
  5. It is commonly addressed with a combination of medication, psychotherapy, and social support.

Frequently Asked Questions (FAQs)

1. Is major depressive disorder a disability?

Major depressive disorder is a crippling psychiatric disorder that negatively impacts our quality of life and may result in a disability if left untreated.

2. What goals should I set for my major depressive disorder?

Try setting short-term goals like finishing a household chore, getting out of bed, getting to a healthy weight, meeting new people, etc. Doing so can make you feel that you are taking control of your life and that you are returning healthily to your normal schedule.

3. What is the difference between major depressive disorder and persistent depressive disorder?

Major depressive disorder involves bouts of depressive episodes, separated by at least 2 months. On the other hand, the symptoms of persistent depressive disorder last for at least 2 years in adults.

4. Can schizoaffective disorder and major depressive disorder coexist at the same time in the same person?

Most mental illnesses are ‘spectrum disorders’ that exist simultaneously with each other. Thus, it is possible for the two disorders to co-exist.

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