Home » Medical and Psychiatric » Depression Everyone occasionally feels sad or blue, but these feelings are momentary or last a day or two. When a person has a depressive illness, it turns upside down daily life, normal functioning, and causes unbearable hardships to the person with the disorder and those who care about him or her. Depression is a common but serious illness. Many people with a depressive illness never seek treatment when the vast majority, even those with severe depression, can get better with treatment.

There are many forms of depressive disorders. The most common are major depressive disorder and dysthymic disorder.

Major depressive disorder, also known as major depression, is a combination of symptoms that interfere with the person's ability to work, sleep, study, eat, and enjoy once–pleasurable activities. Major depression is prevents a person from functioning normally and is disabling. An episode of major depression may occur just once in a person's lifetime, but usually it recurs throughout a person's life.

Dysthymic disorder, also called dysthymia, is characterized by long term ( two years or more ) but less severe symptoms that may not disable a person but can prevent one from functioning normally or getting well. People with dysthymia may also experience one or many episodes of major depression during their lifetimes.

Some forms of depressive disorder exhibit slightly different characteristics than those described above, or they may develop under unique circumstances. They include:

Psychotic depression, which occurs when a severe depressive illness is accompanied by some form of psychosis, such as a break with reality, delusions and hallucinations.

Postpartum depression diagnosed if a new mother develops a major depressive episode within one month after delivery, is estimated to afflict 10 - 15 per cent of women after giving birth.

Seasonal affective disorder (SAD), is the onset of a depressive illness during the winter months when there is less natural sunlight. The depression usually lifts during spring and summer. SAD may be effectively treated with light therapy, but nearly half of those with SAD do not respond to light therapy alone. Psychotherapy and antidepressant medication can reduce SAD symptoms, either alone or in combination with light therapy.

Bipolar disorder, also called manic-depressive illness, is not as common as major depression or dysthymia. Bipolar disorder is characterized by cycling mood changes-from extreme highs (e.g., mania) to extreme lows (e.g., depression).

People with depressive illnesses all do not experience the same symptoms. The severity, frequency and duration of symptoms vary from individual to individual and illness to illness.

Symptoms include persistent sad, empty or anxious feelings, feelings of hopelessness and / or pessimism, feelings of guilt, worthlessness and / or helplessness, irritability, restlessness, loss of interest in once pleasurable activities or hobbies, including sex, fatigue and poor energy levels, have difficulty in concentrating, remembering and making decisions, insomnia, early–morning wakefulness or excessive sleeping, overeating or appetite loss, thoughts of suicide, suicide attempts, persistent pains and aches, headaches, cramps or digestive problems that do not respond to treatment