An estimated 27 percent of Americans meet diagnostic criteria for alcohol abuse or dependence, according to a study published in the journal "Critical Care Nurse" by Mary G. McKinley, RN 1. The damaging effect alcohol has on the brain is clearly characterized by a person’s inability to do simple tasks like walk and talk. While these are short-term impairments, the National Institutes of Health indicates that drinking has a far more extensive impact on the brain.

Mood and Mood Disorders

Mood, also known as temper, is an emotional state. In the most general terms, mood is often defined as being either good or bad. While the Substance Abuse and Mental Health Services Administration indicates that mood disorders, most commonly depression and manic depression, are caused by imbalances in brain chemical activity, alcohol is a drug that works by altering brain chemistry.

Mood Swing Patterns

A study at Santa Ana College in California found that one mood swing that occurs early in a person’s drinking is mild euphoria. This happens when the region of the brain that controls emotion and behavior is impaired by alcohol. More severe emotional outbursts can become more frequent as a person’s drinking increases. And permanent changes to the brain and mood can occur after years of steady drinking.

As A Symptom

One symptom of alcohol abuse and alcohol dependence is frequent mood swings. One of the first mental processes to be affected by alcohol dependence, according to attorney Ron Jourard, a criminal defense lawyer in Canada, is the ability to control mood swings. Frequent emotional outbursts are common for people who chronically abuse alcohol.

Manic Depression

A 1998 study in the journal "Addictive Behaviors" by Eric B. Raimo of the University of California at San Diego, found a small but significant link between manic-depressive disorder and alcoholism. Manic-depressive disorder, according to the Diagnostic and Statistical Manual of Mental Disorders, can be a short-acting, extreme mood swing with a pattern of episodes shifting between euphoria and depression. According the National Institute of Mental health, people who suffer from manic depression are at risk for having other behavioral problems. They also tend to abuse alcohol and other substances.

Mood Swings and Recovery

Even after a person abstains from drinking, mood swings are expected to persist for up to about two years. According to the National Institute on Drug Abuse, medications combined with therapy are an important part of recovery from alcohol dependence. Medications like selective serotonin reuptake inhibitors, known as SSRIs, can help minimize mood swings. Behavioral therapy works by changing a person’s attitudes and feelings about drinking.