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Mood disorders: Symptoms, causes, treatment

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Mood Disorders, Defined

What Is Mood?

Your mood is your general emotional state at any given time. In contrast to emotions, which are short-lived responses to a specific situation, mood reflects a more general feeling that is less likely to have a clear trigger. Whereas emotions can also be extreme, such as euphoria or rage, moods tend to be less intense, such as contentedness or irritability.

In addition, moods don’t last forever, but they do tend to be longer-lasting than simple emotions. For example, your happy mood for the day may be interrupted by the anger and pain of stubbing your toe, but you’ll likely return to your happy mood once that particular emotion has subsided.

What Are Mood Swings?

Mood swings refer to the sudden, often intense shifts in mood, typically from positive to negative or vice versa. Most people experience mood swings from time to time. They can be brought on by external circumstances, such as stress, hunger, lack of sleep, hormones, changes in circadian rhythm, medications, and more. However, if your mood swings are frequent, severe, and/or interfering with your ability to function, they may be indicative of a mood disorder.

What Is a Mood Disorder?

Mood disorders are mental illnesses that affect your typical emotional state. Everyone experiences distressing moods from time to time, but people with mood disorders experience distressing or extreme moods as a baseline. Their feelings are often out of sync with their environment and circumstances.

Two Major Types of Mood Disorders

Psychologists categorize most mood disorders into two categories: depression or bipolar disorder. Specific mood disorders in each category may share common symptoms, but they require their own individual diagnosis.


Depression is characterized by feelings of sadness, loneliness, emptiness, and hopelessness. More than just feeling sad, depression is a medical condition that negatively and directly interferes with your daily life. There are several types of depressive disorders:

  • Major depressive disorder (MDD): MDD, also known as clinical depression, is a form of depression that occurs for at least two weeks, though it can also last months or years. It is also the most common mood disorder: approximately 16 million Americans experience at least one major depressive episode each year.
  • Persistent depressive disorder (PDD): PDD, also known as chronic major depression or dysthymia, lasts longer than MDD (at least two years) but is generally considered less severe.
  • Psychotic depression: Psychotic depression occurs when patients experience MDD alongside psychosis (e.g., hallucinations or delusions). This severe form of depression often requires hospitalization. It is important to note that psychotic depression is different from schizophrenia, which is a psychotic disorder, not a mood disorder.
  • Postpartum depression (PPD): Postpartum depression is common among parents of a newborn. It is different from the more temporary “baby blues” commonly experienced within the first two weeks of a child’s birth.
  • Seasonal affective disorder (SAD): People who experience seasonal affective disorder feel depressed due to the change in seasons. Most often, SAD occurs during the transition into colder, darker seasons, such as fall and winter. Symptoms dissipate as the weather warms in the spring and summer.
  • Disruptive mood dysregulation disorder (DMDD): DMDD is a childhood mood disorder characterized by extreme irritability and outbursts lasting for at least a year.
  • Substance/medication-induced mood disorder: This type of mood disorder is caused by the use of drugs, alcohol , or medication, and it can also occur during withdrawal.
  • Premenstrual dysphoric disorder (PMDD): PMDD is a more severe form of the more commonly known premenstrual syndrome (PMS). In addition to more intense versions of PMS symptoms, PMDD is often accompanied by severe depression, anxiety, or mood swings.

Bipolar Disorder

Bipolar disorder is characterized by extreme shifts in mood and energy. People with bipolar disorder swing from mania or hypomania (“high highs”) to depression (“low lows”). There are three main types of bipolar disorder:

  • Bipolar I: Bipolar I is characterized by manic and depressive episodes. Manic episodes last at least a week or result in hospitalization, while depressive episodes last at least two weeks. People with bipolar I may also experience depression with mixed features. This form of bipolar disorder typically has the most extreme symptoms.
  • Bipolar II: People with bipolar II experience hypomanic and depressive episodes, but not full-on mania.
  • Cyclothymic disorder: People with cyclothymic disorder have experienced hypomanic and depressive symptoms for at least two years (one year for minors), but their symptoms are milder than those of bipolar I or II.

What Causes Mood Disorders?

There is no single, specific cause for mood disorders. However, there are multiple risk factors that may increase your likelihood of developing a mood disorder, including:

  • Genetics: If someone in your family has depression or bipolar disorder, you may be more likely to develop a mood disorder.
  • Biochemistry: There’s evidence to suggest that brain structure and the balance of chemicals in the brain may increase a person’s risk for mood disorders.
  • Trauma: Experiencing trauma at any age, but especially in childhood, can increase your risk for multiple mental health disorders, including mood disorders.
  • Illness: Dealing with chronic illness, pain, or disability may increase your risk for depression.
  • Medications: Certain medications may have depression or extreme mood swings listed as potential side effects.
  • Addiction: Substance abuse is a significant risk factor for substance-induced mood disorder as well as major depression.

Mood Disorder Diagnosis

Is a Mood Disorder a Mental Illness?

Yes, mood disorders are a form of mental illness. “Mental illness” is an umbrella term covering a variety of mental health conditions, including personality disorders, developmental disorders, trauma-related disorders, anxiety disorders, and psychotic disorders—to name a few.

Do I Have a Mood Disorder?

The only way to know for certain if you have a mood disorder is to seek a professional diagnosis. If you are suffering from depressive symptoms, a therapist can determine whether they are symptomatic of a type of depression or a depressive state of bipolar disorder. Click here to find a mood disorder therapist near you.

Mood Disorder Treatment

Find a Therapist

Mood disorders can’t be cured, but they can be treated effectively. People with mood disorders often see improvement under a variety of therapies, such as:

  • Cognitive behavioral therapy: Helps people identify unhelpful or negative thought patterns that affect their emotions and behaviors
  • Eye movement desensitization and reprocessing (EMDR): Uses rapid eye movement to allow individuals to process heightened emotions or traumatic experiences
  • Interpersonal and social rhythm therapy (IPSRT): Promotes the stabilization of biological and social rhythms to reduce disruptions in life routines that may trigger symptoms of bipolar disorder
  • Electroconvulsive therapy (ECT): Stimulates the brain via small, safe electric currents to induce a minor seizure to improve brain chemistry
  • Transcranial magnetic stimulation (TMS): Stimulates the brain via magnetic fields to improve mood regulation

In addition to therapy, people with mood disorders often respond well to certain medications, such as mood stabilizers or antidepressants.

Ready to start feeling better? Click here to find a mood disorder therapist near you.

Get Help Now

Whether you’re struggling with depression, bipolar disorder, or another type of mood disorder or mental illness, it’s important to remember that you are not alone. Help is available now. If you are in crisis, call, text, or chat with one of the following hotlines:

About the author

The editorial team at works with the world’s leading clinical experts to bring you accessible, insightful information about mental health topics and trends.

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