What are the symptoms?
Depression can cause different symptoms in different people, and they may be hard to notice at first. For example, a child may seem grouchy and irritable. An older adult may be forgetful. If you think a loved one is depressed, learn more about what symptoms to look for, and urge the person to get help if needed.

People who are depressed may:
  • Think and speak more slowly than normal
  • Have trouble concentrating, remembering and making decisions
  • Display changes in their eating and sleeping habits
  • Lose interest in things they enjoyed before they were depressed
  • Have feelings of guilt and hopelessness, wondering if life is worth living
  • Think a lot about death or suicide
  • Complain about problems that donít have a physical cause

All of these symptoms can cause a problem with your quality of life. If you have had a few of these symptoms for at least 2 weeks, talk to your doctor. You may have depression that requires treatment. Depression may give one or more of these symptoms:

  • Low mood level or sadness
  • Lack of joy or interest in activities that were joyful before
  • Pessimism
  • Feel of guilt of something without any substantial reason to feel so
  • Inferiority thoughts
  • Irritability
  • Slowness in the thought process and in interpreting sensorial stimuli
  • Slowness of digestion or other internal physical processes, and symptoms caused by this slowness, for example inflated stomach, constipation or difficulties by urination
  • Slow physical reactions

Depression can be a mild disease that only causes some annoyance in the daily life, but can also get very serious and make a person totally unable to work and unable to participate in social life. By depression of some severity, there is also a greater risk of suicide. It can occur in all age classes. In teenagers lack of interest in school work, withdrawal from social life and difficult mood can be signs of depression.

TYPES OF DEPRESSION
Depression is often divided into subtypes according to exhibited symptoms:

  1. Mono-polar depression and dysthymic disorder. By mono-polar depression there are pure depressive symptoms. Mild cases of mono-polar disorder that do not affect a persons ability to work and to participate in social activities are often called dysthymic disorder
  2. Bipolar disorder (manic-depressive disease) and cyclothymic disorder
    In this condition there are periods with symptoms of depression - the depressive phase, alternating with periods of elevated mood level with increased mental and physical activity - the manic phase. In the manic phase, the affected person also sleeps poorly and has concentration difficulties. A mild form of this disease is called cyclothymic disorder
  3. Manic disorder is characterized by abnormally elevated mood, by unrealistic optimism, by lack of sleep and by hyperactive behaviour. Many psychiatrists think that this disorder is simply the same disease as bipolar disorder where the depressive face has not yet occurred.
  4. Depression with mainly physical symptoms. Sometimes the physical symptoms of depression are alone or dominant, as for example: Digestive problems, constipation, difficulties with urination, slow response to sensorial stimuli or slow physical reactions

CAUSES OF DEPRESSION
Two or more factors can have an effect simultaneously to cause depression. Depression can be an independent disease, or a part of other disease. Depression is also divided into different subtypes according to cause:

  • Reactive depression
    This disease is simply a result from psychological stress, physical struggle or mental straining without proper rest or sleep over a long time period. The straining will simply wear out the nervous system or deplete the organism from nutrient necessary for the nervous system to work properly.
  • Endogenous depression
    When there has not been any period of stress, straining or lack of rest that can explain the condition, the condition is often called endogenous depression. Inheritance is thought to be a part of the cause
  • Depression by physical disease
    Depression or depressive symptoms may be a symptom of physical disease. This is perhaps the most common cause of depression. Diseases often associated with depression are: Heart disease, Parkinson's disease, stroke, hypertension or Cushing's syndrome. Mononucleosis or flu may trigger depression that continues after the infection has gone.  By lack of thyroid hormones, hypothyroidism, the metabolism in the whole body is slowed down, including the production of neurotransmitters in the brain. Therefore depression is an important symptom of hypothyroidism
  • Depressive symptoms as a consequence of unsound lifestyle
    A general unsound lifestyle with too less exercise, too much of stimulants like alcohol, coffee or tea, too less of important nutrient and too much of sugar and fat may give depressive symptoms, as well as physical problems
  • Postnatal depression
    Women will often have a period of depression after pregnancy and berth of the baby Pregnancy and berth is physically and mentally exhausting, and may drain the body for nutrient. This in turn can cause depressive symptoms
  • Seasonal affective disorder
    Depression can occur in cold and dark periods of the year and go away in warm and light periods. Light stimulates brain activity, and lack of light is a causative factor

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