Possible Causes of Mood Swings

Mood swings are rapid and often extreme, fluctuations in one's emotional state, involving alternating between feelings of happiness and well-being and feelings of anger, irritability, or depression.


Among the possible causes of mood swings is an imbalance in the brain chemicals associated with mood regulation, as in the case of bipolar disorder, and the hormonal changes associated with the menstrual cycle or menopause. In addition, mood swings may occur in men who abuse steroids (often called 'roid rage).

Mood swings are also common with depression, especially untreated depression, where moods can fluctuate from irritability to extreme sadness to an angry outburst.

Everyone experiences mood swings once in awhile, but when they start to become so often or so intense that they disrupt your everyday life, your work, and even your relationships, it's time to see a doctor. You may have a mood disorder such as depression, bipolar disorder or borderline personality disorder (BPD).

Symptoms of Depression

If you're having trouble with mood swings, you could be depressed. Other symptoms of depression include:

  • Feeling sad, hopeless and worthless
  • Having difficulty sleeping
  • Eating too much or too little
  • Being tired and fatigued
  • Not finding enjoyment in the activities you normally enjoy
  • Having difficulty concentrating and/or making decisions
  • Having thoughts of death or suicide

Symptoms of Bipolar Disorder

Mood swings are one of the classic symptoms of bipolar disorder, which is characterized by episodes of mania or hypomania, episodes of depression, and episodes of both called mixed episodes. There are two main types of bipolar disorder: Bipolar I and Bipolar II.

An episode of mania can have symptoms like fast-talking, feeling energetic, being extremely talkative, engaging in risky behavior, being on edge or irritable, needing less sleep than normal and being more active than you normally are.

A depressive episode may include feeling sad or worthless, crying, lacking energy, feeling wiped out, having trouble concentrating, difficulty sleeping, eating either too much or not enough, thoughts of death or suicide and losing pleasure in activities you once enjoyed.

Bipolar I is diagnosed when you have had at least one manic episode. You may also have had depressive or hypomanic episodes. Bipolar II is diagnosed when you've had at least one depressive episode lasting two weeks or more and one hypomanic episode that lasted at least four days, but never a manic episode.

Symptoms of Borderline Personality Disorder

Borderline personality disorder is another mental health disorder that could be behind your persistent mood swings. Here are other symptoms:

  • The mood swings are intense and variable and can last from a few hours to a few days.
  • Impulsive and risky behavior. For example, engaging in unprotected sex or substance abuse.
  • Extreme reactions to abandonment, whether it's real or you just think it's real. These reactions may include depression, rage or panic.
  • Often feeling empty or restless.
  • Threatening suicide or engaging in self-harming behaviors like cutting.
  • Having emotional, intense relationships with others that are characterized by extreme feelings about the person.
  • Anger issues, which can include outbursts, inappropriate anger and an inability to control your temper.
  • Having dissociative symptoms. For example, feeling like you've lost time or are outside of your own body watching everything happen.

If mood swings come on suddenly, are highly irrational or turn suicidal, seek immediate medical attention.

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Article Sources

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  3. Bowen R, Peters E, Marwaha S, Baetz M, Balbuena L. Moods in Clinical Depression Are More Unstable than Severe Normal Sadness. Front Psychiatry. 2017;8:56. https://doi.org/10.3389/fpsyt.2017.00056

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Additional Reading

  • "Bipolar disorder." National Institute of Mental Health (2015).
  • "Borderline Personality Disorder: Symptoms." Mayo Clinic (2015).