What Are the Causes of Major Mood Swings?

Major mood swings, or dramatic, abrupt changes in someone's mood, have a wide variety of causes. Women may experience significant changes in their mood prompted by gynecological processes. Major mood swings may also occur as a symptom of medical problems such as psychiatric disorders, conditions that affect the central nervous system, and other diseases. People may also induce their own mood swings through stress, taking medications, and substance abuse.

Premenstrual syndrome (PMS), menopause, perimenopause, and hormonal changes during and after pregnancy are frequently responsible for mood swings in women. Women, especially those in their late 20s and early 30s, often experience monthly PMS which can cause major mood swings. Symptoms of PMS often vary in intensity from month to month, so those who suffer from PMS may only experience minor changes in their mood. Similarly, older women who are approaching or going through menopause may experience major mood swings caused by hormonal changes in their body. Additionally, sleep disturbances brought on by hormonal changes during menopause may also induce mood changes.

In addition to hormonal changes that occur during pregnancy that may bring on mood swings, women may experience serious mood swings after childbirth as a symptom of postpartum depression. Major postpartum mood swings do not include the baby blues, or small attitude changes that last for only a few days. The most serious cases of postpartum depression lead to severe mood swings that may be a sign of postpartum psychosis, which also includes paranoia and hallucinations. These bouts of depression will often last for weeks or months and, in some cases, can become dangerous for both mother and child.

People with psychiatric disorders, specifically personality disorders and bipolar disorder, often experience major mood swings. The specific causes of these disorders are frequently debated, but it is believed that they result from a combination of genetics and upbringing. Treatments for mental illness may include psychotherapy and medications; in extreme cases of those with psychotic mood swings, hospitalization may be necessary.

Conditions that affect the central nervous system, such as dementia, brain tumors, and meningitis, often cause mood swings. In later stages of cardiovascular diseases and lung diseases, such as emphysema, the brain is often starved of blood and oxygen needed to properly function, which may also result in major mood swings. Medications taken regularly for a disease or a condition may also cause changes in mood as a side effect.

Additionally, those who abuse prescription drugs, street drugs, and alcohol are also susceptible to severe mood swings that coincide with their cycle of usage. An abuser may be happy or euphoric while using and become angry or depressed as the drugs leave his or her body.