What Is the Difference Between Unipolar and Bipolar Depression?

To put it simply, unipolar depression is another name for major depressive disorder (MDD), also known as clinical depression.

This mood disorder is characterized by a persistent feeling of sadness or a lack of interest in things that you used to enjoy.

To consider a diagnosis of MDD, a health professional will assess whether you meet the criteria set in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5). This reference handbook helps mental health professionals make accurate diagnoses.

According to the DSM-5, to receive an MDD diagnosis, you must experience:

• symptoms for 2 weeks or longer
• episodes of depression or significant and persistent loss of interest, or both
• a change in the way you previously functioned

Diagnostic criteria also include experiencing 5 or more of the following symptoms in a 2-week period:

• feeling sad or irritable
• trouble with falling asleep
• feeling worthless or guilty
• intense feelings of restlessness
• change in appetite or sudden weight loss
• lack of energy or unusual sense of tiredness
• loss of interest in activities you once enjoyed
• difficulty with decision making or concentrating
• having thoughts about harming yourself

Why call it ‘unipolar’ then?

“Unipolar depression focuses mostly on the depressed mood state rather than the two-pronged presentation of bipolar depression, which includes the movement between the depressive state as well as the expansive or elevated mood state,” explains Lovern Moseley, a licensed psychologist in Boston.

In other words, unipolar means there’s one prolonged mood episode — in this case, depression. This is in comparison with other mental health conditions, like bipolar disorder, which may lead you to experience changes in your mood, from depression to mania, an elevated mood state.

Bipolar depression is a term used to describe depression within bipolar disorder. In other words, bipolar depression isn’t a condition but rather a symptom of depression for someone who lives with bipolar disorder.

“Bipolar disorder is a recurring mood disorder characterized by alternating episodes of elevated mood or mania and sad or irritable mood or major depression,” explains Moseley.

Someone who receives a diagnosis of bipolar disorder may experience periods when they feel energized and optimistic, known as manic episodes. On the flip side, they could experience periods of feeling very down or even hopeless, known as depressive episodes.

It’s the alternation between mood episodes that differentiates bipolar depression from clinical depression.

Symptoms

The most significant difference between clinical depression and bipolar disorder is that the first one doesn’t include episodes of mania as a persistent or major symptom.

According to Moseley, “while it’s possible to experience brief episodes of mania during a major depressive episode, a primary indicator of major depressive disorder is experiencing symptoms of depression for 2 weeks and being a significant change from previous functioning.”

This means that while the symptoms may be the same, it’s the length of time you experience them that makes a difference.

Causes

Experts still haven’t established the cause of MDD or bipolar disorder. There’s likely a combination of factors that come into play.

Causes for both conditions could include poor mood regulation by the brain to a family history of bipolar disorder and depression to environmental factors like adverse childhood experiences or stressful life events.

The causes of unipolar and bipolar depression may also vary for each person.

Treatment

In general terms, both depression and bipolar disorder can be treated with a similar approach involving education, medications, and psychotherapy.

For clinical depression, psychotherapy is usually the first course of action.

The most common approaches to treating major depression include:

• cognitive behavioral therapy (CBT)
• interpersonal therapy (IPT)
• acceptance and commitment therapy (ACT)
• short-term psychodynamic psychotherapy (STPP)

Antidepressants are commonly used in the treatment of depression.

In the case of bipolar disorder, the most common psychotherapy approaches used include:

• cognitive behavioral therapy (CBT)
• family focused therapy (FFT)
• interpersonal and social rhythm therapy (IPSRT)
• dialectical behavioral therapy (DBT)

Medication to treat bipolar disorder differs by focusing on “reducing your mood intensity and increasing the stability of the mood,” explains Moseley.

This prescription treatment could include:

• antipsychotics
• mood stabilizers
• antidepressants
• anticonvulsants

The short answer is no. The long answer is, it’s complex — and more research is needed.

With the information we have now, “MDD and bipolar disorders are not diagnosed concurrently,” says Kailey Hockridge, a licensed professional clinical counselor in Los Angeles.

Even so, Hockridge explains how one of the benefits of these diagnoses is to “empower you, to have a name for your experiences, and thus be able to seek out appropriate support to provide you with relief and understanding.”

Whether you’re experiencing clinical depression or bipolar depression, you have options to help you manage your symptoms.

If you’re unsure about what you may be experiencing (or you’re pretty sure and want help managing), consider speaking with a licensed mental health professional as a first step. It may aid you in gaining clarity on what you’re going through. They can also work with you to determine the best course of treatment.