Understanding Euthymia in Bipolar Disorder

Euthymia in bipolar disorder is a term used to describe a relatively stable mood state, where you are neither manic/hypomanic nor depressed.

However, some dictionaries have offered variations of the definition which can be confusing when used in the context of a mental illness. To complicate matters even further, a significant number of people diagnosed with bipolar euthymia will show signs of depression or anxiety, casting into doubt as to what the term actually means.

Varying Definitions

The confusion in the definition of euthymia begins with the root word itself. In Greek, the prefix eu- means "good or well," while -thymia is derived from the Greek word "thymus," meaning "mind." This would suggest that a person in a euthymic state is in a good state of mind.

Other dictionaries have expanded the definition to suggest a positive or even elevated mood state, not unlike that used to describe euphoria. When used in philosophy, in fact, euthymia describes a state of gladness, good mood, and serenity (in reference to one of the root goals of human existence).

The same definition cannot be applied to medicine. When used in a clinical context, euthymia is not so much a good state as it is a neutral one in which you may neither be particularly happy nor sad. You may not even feel "good" per se but will at least be in a state where you are better able to function on a daily basis.

With that being said, some people with euthymia will feel markedly improved. However, others will experience signs and symptoms suggestive of depression or anxiety.

Euthymia and Anhedonia

It is not uncommon to be diagnosed as euthymic and have symptoms of anhedonia, a mood state defined as the reduced ability to feel pleasure. Anhedonia may be experienced physically, wherein you get no pleasure from touching, eating, or sex, or socially, where you are disinterested in or unable to gain pleasure from social situations.

Anhedonia is not depression per se but is rather a core symptom of depression and other mood disorders, including schizophrenia. Some people will describe anhedonia as "emotional flatlining."

Unfortunately, there is no consensus as to the appropriate treatment of anhedonia or any drugs that specifically target anhedonia as a condition.

With that being said, people with anhedonia often benefit from increased social support as well as the combined use of antidepressant drugs and psychotherapy. Wellbutrin (bupropion), an antidepressant used to treat bipolar depression, may be useful in improving libido.

Euthymia and Anxiety

Euthymia and anxiety can also co-occur in people with bipolar disorder. The type and severity of anxiety symptoms can vary from person to person and may be characterized by one or several of the following disorders:

• Agoraphobia
• Generalized anxiety disorder (GAD)
• Obsessive-compulsive disorder (OCD)
• Panic disorder
• Post-traumatic stress disorder (PTSD)
• Social anxiety disorder (SAD)

The anxiety disorder may have been pre-existing alongside bipolar disorder, or it could something that developed after (or in response) to bipolar treatment

As opposed to anhedonia, which has no established course of treatment, anxiety disorders would be treated after a diagnosis according to the criteria in the Diagnostic and Statistical Manual of Mental Disorders (DSM) issued by the American Psychiatric Association.

Cause

It is unclear why some people with bipolar euthymia experience anhedonia, while others experience anxiety or no symptoms at all. In recent years, a number of psychologists have suggested that our very understanding of euthymia may be askew, wherein the absence of disease is often construed as having good mental health. This is especially true with regards to euthymia.

A bipolar person in a euthymic state will often not be willing or able to alter their current mood state after the resolution of an acute manic or depressive episode. It may that he or she fears "tipping the boat" and has become less responsive to outside stimuli, either consciously or unconsciously.

Whatever the cause, the resulting inflexibility can make it difficult to adapt to various situations or sensations. Without the ability to adapt, the person will be less able to experience pleasure and have a general tendency to experience negative emotions more frequently, intensely, and readily.

As such, euthymia is not necessarily an indication that a treatment has "worked" but is rather the state by which the course of treatment may need to be monitored and adjusted.