A major depressive episode is a significant period of mood, behavioral, and psychological changes often associated with depression. Depressive episodes may occur once or repeatedly, and may be a sign of a larger mood disorder, such as bipolar disorder. Psychology experts define a major depressive episode as adherence to at least five of the major symptoms of negative impairment over at least a two week period. Some of the symptoms common to a major depressive episode include sleep and energy changes, appetite changes, consistent depression or irritability, lack of pleasure or interest in daily activities, and episodes of lethargy or agitation.
The diagnosis of a major depressive episode is outlined in many psychology reference manuals, including the Diagnostic and Statistical Manual of Mental Disorders, better known as the DSM-IV. According to the diagnostic outline, patients may have a combination of at least five qualifying criteria to be considered in the midst of a major depressive episode. Symptoms considered in the diagnosis should not be attributable to any existing medical or drug-induced condition. To be considered for diagnosis, the symptoms must include consistent symptoms of depression, or a marked lack in interest or enjoyment of life for at least two weeks.
Feeling deeply sad, hopeless, or depressed is probably the most significant symptom of a major depressive episode. Thoughts of death or suicide may be common, and some studies show a link between depressive episodes and an increased risk of suicide. People experiencing feelings of depression can go through various manifestations of the condition, including crying fits, increased irritability, emotional numbness, physical symptoms such as headaches, and chronic fatigue.
In a major depressive episode, sleep and energy levels can be significantly affected. Sleeping too much or too little can both be symptoms of major depressive episodes, so long as the changes marks a significant alteration from normal sleeping patterns. While it may not be surprising that those suffering from lack of sleep will become lethargic or constantly fatigued, even people sleeping far more than usual may also feel exhausted all the time.
Increased or decreased appetite that results in significant weight gain or loss may be considered a symptom of a major depressive episode. People suffering from depression-related appetite issues may not feel hungry or feel constantly hungry. Some may experience food cravings, especially for sugary foods or those high in carbohydrates. Decreased appetite may be a somewhat more common symptom of a major depressive episode.
A significant depressive episode may resolve without psychological treatment, but it can also be an important sign that a person is in need of aid. Episodes can be brought on by acute traumas, such as the death of a loved one, but may also be signs of a larger mood disorder with no immediate cause. A person in the midst of a depressive episode can be in danger of harming his or her career, personal relationship, or even committing suicide. Psychological evaluation can help determine if symptoms of depression may add up to a major depressive episode.