Unipolar depression is another name for major depressive disorder. The term unipolar means that this form of depression does not cycle through other mental states, such as mania.

This is how unipolar depression differs from bipolar conditions, as in contrast, bipolar conditions cause periods of both depression and mania.

However, having unipolar depression does not mean that a person is depressed at all times. People with major depressive disorder may experience periods of remission that alternate with periods of depression relapse. They may also feel happier when circumstances change, especially if they have the subtype of major depressive disorder called atypical depression.

Unipolar depression is one of the most common mental health diagnoses. As well as producing a depressed or sad mood, it can cause physical symptoms and significant difficulty managing daily tasks and relationships. In 2019, 7.8% of all adults in the United States had at least one major depressive episode.

Keep reading to learn more about unipolar depression, including the causes, symptoms, and treatment methods.

Person behind a fence, trapped, to represent symptoms of unipolar depressionShare on Pinterest
Javier Pardina/Stocksy

Unipolar depression is another name for major depressive disorder. This mental health condition affects both mental and physical health.

The diagnostic criteria for major depressive disorder are as follows:

A person must have at least five of the following symptoms:

  • Depressed mood: A person feels sad or depressed for the majority of the day on most days. They may feel empty, hopeless, sad, or uncertain about the future. In children, these symptoms might manifest as behavioral issues or irritability.
  • Loss of pleasure: A person may get little or no pleasure from activities that they once enjoyed.
  • Weight or appetite changes: A person may gain or lose 5% or more of their body weight without trying or experience changes in appetite, such as eating too much or too little.
  • Sleeping issue: A person may sleep too much or too little.
  • Fatigue: A person may feel physically and emotionally exhausted to the extent that it interferes with their motivation and daily tasks.
  • Concentration issues: A person may have difficulty focusing, paying attention, or thinking clearly. Some people may experience brain fog.
  • Thoughts of death or suicide: A person may have intrusive thoughts of dying, harming themself, or dying by suicide.

A person will only meet the criteria for a diagnosis if their depressive symptoms are not due to bipolar disorder or another health condition. Their symptoms must cause significant distress and not be due to medication or a physical health condition. They must also never have experienced a manic episode.

The symptoms of depression can also cause secondary symptoms, such as:

  • trouble getting or keeping a job
  • relationship conflict
  • trouble studying or excelling at school
  • difficulties with self-care

People with depression view the world through a distorted lens, which can affect what they think and feel about other people and themselves. As a result, they may experience interpersonal conflicts, low self-esteem, rejection sensitivity, and similar challenges.

The primary difference between unipolar depression and bipolar depression is that a person with unipolar depression experiences only depression rather than cycles of depression and mania, which characterize bipolar disorder, or bipolar depression.

People with bipolar depression tend to experience periods of depression similar to those of major depressive disorder, but they also experience times of mania, during which their mood is very elevated. During manic episodes, a person might be unusually happy. They may make impulsive or harmful decisions, such as spending too much money.

People with unipolar depression are not necessarily always depressed. Some may appear happy, pretend to be happy, or experience times during which their depression symptoms improve.

One subtype of major depressive disorder, atypical depression, tends to be chronic. However, it also responds better to changes in circumstances, meaning that a person may be happier and experience fewer symptoms when their situation improves. This is not the same as the mood cycling that occurs with bipolar depression.

Major depressive disorder is not the only form of depression. Other forms of depression that are unipolar and do not involve manic episodes include:

  • Postpartum depression: This form of depression occurs following the birth of a baby.
  • Seasonal affective disorder: This seasonal type of depression typically occurs in the winter.
  • Persistent depressive disorder: This chronic form of depression tends to have less severe symptoms than major depressive disorder.
  • Psychotic depression: This type of depression causes a person to have psychotic thoughts. Psychotic thoughts are those disconnected from reality, such as delusions and hallucinations.

Learn more about the different types of depression.

Major depressive disorder is a complex condition that has genetic, psychological, social, and interpersonal causes. These factors interact with one another to lead to depression. For example, a person may have a genetic predisposition to depression that trauma or stress then activates, triggering symptoms.

Researchers do not fully understand what causes depression, but they do know that disruptions in brain chemicals called neurotransmitters play a role in depression. Antidepressants act on brain chemicals such as serotonin, norepinephrine, and dopamine, suggesting that these chemicals play an important role in mood.

Some risk factors for developing unipolar depression include:

  • certain medical conditions, including thyroid disorders
  • family history of depression
  • trauma and adverse childhood experiences

Major depression causes a low and depressed mood. A person may experience the world as primarily negative and be subject to cognitive distortions that affect their relationships, work, and school performance.

The symptoms of depression include:

  • feelings of worthlessness or guilt
  • feeling hopeless about the future
  • being unable to get pleasure from hobbies, relationships, or other previously enjoyed activities
  • trouble thinking clearly or making decisions
  • brain fog
  • thoughts of self-harm or suicide
  • eating too much or too little
  • unexplained weight gain or weight loss
  • trouble sleeping or sleeping too much
  • low energy
  • slowed movements or speech
  • feeling restless or pacing

Depression symptoms can cause secondary problems, such as unemployment or inferior academic grades.

Various antidepressants can effectively treat depression, with the best option depending on several factors. These include:

  • the person’s overall health
  • the side effects the person feels they can tolerate
  • the subtype of major depression

A person may need to try several medications or different dosages of the same medication before they get relief from their symptoms. Working with a knowledgeable psychiatrist and talking about side effects and other treatment concerns may help a person find relief faster.

Psychotherapy techniques, especially those designed to treat depression, such as cognitive behavioral therapy (CBT) and interpersonal therapy, can help a person cope better, implement positive lifestyle changes, and manage life with depression.

Electroconvulsive therapy, vagus nerve stimulation, and transcranial magnetic stimulation, which are therapies that directly stimulate the brain, may also help, especially if other treatments prove ineffective.

Some people find that they benefit from making lifestyle adjustments, such as exercising more, eating a well-balanced diet, practicing meditation, or starting a new hobby.

Depression is difficult to treat and often chronic, which means that a person may experience remission and then a relapse.

A depression treatment plan that is comprehensive and includes medication, therapy, and lifestyle changes may help a person cope better during depression relapses.

A 2019 study showed that certain factors increase the likelihood of depression remission. These include:

  • employment
  • less anxiety
  • a better quality of life
  • less severe depression
  • less chronic depression
  • not experiencing complicated grief
  • not having a history of childhood adversity

Unipolar depression is another name for major depressive disorder.

It can affect virtually every aspect of a person’s life, including their relationships, career, education, and sense of self. Myths about depression can undermine a person’s ability to access or seek treatment.

Although major depression is challenging to treat, remission is possible, especially when a person has access to knowledgeable and comprehensive support.

People who experience depression should seek prompt mental health care. A primary care physician can often refer a person to a qualified and supportive mental health professional.