Mood swings are often thought to be synonymous with having manic depression. The presence of “mood swings,” however, is not enough to determine that a person is manic-depressive. Many depressed persons can have ups and downs in their mood. The distinction is important because manic depression is another name for a condition called bipolar disorder, and depression in bipolar disorder is treated differently from major depression.
Bipolar disorder is less frequent than major depressive disorder, occurring in approximately 3% of the population. It is also more closely associated with family history and, in general, is a more severe illness. Bipolar depression differs from major depression in that the individual has to have experienced at least one manic or hypomanic episode in his or her lifetime. Although experiencing mania or hypomania is often referred to as having mood swings, specific criteria define these mood states. Mood swings can mean many things to many people—from constant crying to episodes of irritability or anger.
Recent research has also determined that the symptoms accompanying major depressive disorder may vary dramatically over time. Such variability can be misinterpreted as mood swings. Manic or hypomanic episodes are strictly characterized by a decreased need for sleep (not the same as insomnia), inflated self-esteem ( grandiosity ), rapid and pressured speech (the need to keep talking ), euphoric or irritable mood, and increased activity level. Duration criteria are required to make the diagnosis as well. It is important that the strict criteria are used because depression alone can be a cause for irritability and anger management problems, both of which can look like mood swings.
Once it is determined that a manic or hypomanic episode has occurred in the past, then the diagnosis must reflect that, because the treatment approach may be different and different risks are associated with taking antidepressants.