How do major depressive disorder persistent depressive disorder and bipolar disorder differ?

What Is the Difference Between Depression and Bipolar Disorder?

Depression and bipolar disorder are two mood disorders that have many similarities. However, they have key differences that are essential to understand for the sake of effective treatment. 

Mental health is becoming more of a mainstream topic, an incredible advancement that normalizes the experiences of many. As such, isn’t uncommon to hear someone say they’re feeling depressed.

However, clinical depression, also known as major depressive disorder, isn’t just feeling sad. It is a persistent feeling of hopelessness and emptiness, losing interest in things that used to excite you, and several other symptoms including changes in sleep, appetite, and thinking.

Depression

• Persistent feeling of hopelessness and emptiness

• Changes in appetite, sleep, thinking

• Significant fatigue

Bipolar Disorder

• Marked by episodes of mania or hypomania and depression

• May cause impairment or require hospitalization

• May have feelings of extreme energy when manic

Similarly, some may casually say they’re bipolar because they’re feeling a wide range of moods. But bipolar disorder is marked by episodes of mania or hypomania and depression that significantly impact your life.

Read on to learn more about the symptoms, causes, and treatment for these two disorders.

Symptoms of Depression

A diagnosis of a major depressive episode includes experiencing some of the following symptoms for the majority of the day and nearly every day for at least two weeks:

• Consistent sad and hopeless mood
• Feeling worthless or guilty
• Loss of interest in activities that were once pleasurable
• Significant fatigue
• Moving and/or talking slowly
• Issues such as oversleeping or challenges falling asleep
• Decreased ability to think or concentrate
• Loss or increase in appetite
• Weight changes
• Suicidal ideation
• Somatic pains that are not explained by other physical ailments

To meet the diagnostic criteria for major depression, you will need to experience some of these symptoms consistently. However, everyone experiences depression differently. Some may experience all of these symptoms, others may experience fewer symptoms. It is important to see a licensed mental health professional to appropriately evaluate symptoms of depression.

Symptoms of Bipolar Disorder

Bipolar disorder has three different variations: bipolar I, bipolar II, and cyclothymia. Bipolar disorder exists on a spectrum.

Bipolar I is defined by the following symptoms:

• Periods of experiencing mania for at least one week. Mania is marked by feelings of elation, grandiosity, irritability, and/or extreme energy
• The disturbance is sufficient to cause marked impairment or require hospitalization
• Depressive episodes generally occur along the course of the illness

Remember, you don’t have to experience all of these symptoms to experience bipolar I.

Bipolar II is defined by the following symptoms:

• Hypomania, which consists of less pronounced mania symptoms, for at least 4 days
• Intermittent depressive episodes that last for at least two weeks and severely impact daily functioning

Cyclothymia is defined by the following symptoms:

• Experiencing hypomanic symptoms that do not constitute a hypomanic episode over a 2-year period
• Experiencing depressive symptoms that do not constitute a major depressive episode over a 2-year period

Causes of Depression

Depression has many different factors that can contribute to its emergence. These include genetic, temperamental, brain, neurotransmitter, and environmental contributions.

Causes of Bipolar Disorder

The exact cause of bipolar disorder is still unknown, however, there are risk factors that are known to make the development of bipolar disorder more likely.

A risk factor is something that increases the likelihood of developing a condition. First, bipolar disorder is known to have a strong genetic link, meaning if you have a history of bipolar in your family, you are at a higher risk for developing the disorder.

Childhood trauma can increase the risk of developing bipolar disorder to some degree. Stressful life events, like having a child or losing a parent, may be a trigger for a bipolar episode. Finally, bipolar disorder often co-occurs with substance use disorders.

How to Receive a Proper Diagnosis

There are no specific medical tests that determine if you have major depressive or bipolar disorder. Laboratory tests are sometimes ordered to rule out potential medical contributions to your symptoms. The diagnosis is made clinically, meaning mental health professionals will evaluate your current symptoms and psychiatric history to make the diagnosis.  

For this reason, it can be helpful to work with a psychiatrist, psychotherapist, and general practitioner. This can increase the chances of getting a precise diagnosis and feeling relief sooner.

Finding Relief

It may be important to work with a team of professionals including a psychiatrist, psychotherapist, and general practitioner.

While this level of care isn’t always accessible to everyone, it is helpful to have a team of providers that can collaborate on aspects of your treatment.

Treating Major Depression

Depression is typically treated with psychotherapy and antidepressant medications. However, 20% to 30% of individuals do experience treatment-resistant depression.

In the case of treatment-resistant depression, neuro-therapeutic interventions such as ketamine, transcranial magnetic stimulation (TMS), or electroconvulsive therapy (ECT) may be suggested.

Treating Bipolar Disorder

It is incredibly important that bipolar disorder is diagnosed correctly and isn’t misdiagnosed for unipolar depression. This is because antidepressants can potentially trigger a manic episode. 

Similar to depression, bipolar disorder is typically treated with psychotherapy and psychiatric medications, in this case often a combination of mood-stabilizing and the newer antipsychotic medications. Developing healthy routines such as exercise and proper sleep hygiene can also provide benefit.

A Word From Verywell

Whether you're experiencing depression or bipolar mood swings, you are worthy of care. Consider seeking out a mental health professional. Thanks to online therapy, mental health resources have never been more accessible.

Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

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By Julia Childs Heyl
Julia Childs Heyl, MSW, is a clinical social worker and writer. As a writer, she focuses on mental health disparities and uses critical race theory as her preferred theoretical framework. In her clinical work, she specializes in treating people of color experiencing anxiety, depression, and trauma through depth therapy and EMDR (eye movement desensitization and reprocessing) trauma therapy.

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