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
This condition is characterized by abnormally elevated mood, by unrealistic optimism, by lack of sleep and by hyperactive behavior. 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.

~TREATMENT OF DEPRESSION~
Serious or prolonged depression is often treated with anti-depressive medication. Medicines used against depression generally increase the level of neurotransmitters like serotonin in the central nervous system, or they mimic the neurotransmitters.
The medications mostly used today increase the serotonin concentration by decreasing the removal of serotonin from the space around nerve cells. Examples of this medication type are: Fluoxetine (Prozac), fluvoxamine (Luvox), paroxetine (Paxil), escitalopram (Lexapro, Celexa), sentraline (zoloft).
By bipolar disorder in the manic face, heavy tranquilizers (neuroleptica) are used to stop the manic symptoms. By bipolar disorder, lithium salts are sometimes used to stabilize the condition, and prevent new outbreak of depressive or manic faces.
Psychotherapy is sometimes used by depression, usually in combination with medication.
Sometimes serious depression is treated by applying electric shock through the head, electroconvulsive therapy. The shock induces epileptic eruption of nerve signals through the brain and this gives cramps throughout the body. The cramps are alleviated or stopped by applying anaesthesia before the electroshock. This form of treatment is controversial, since it can cause memory loss and is suspected of causing brain damage. The possibility of brain damage is however denied by most psychiatrists.
By seasonal depression, light therapy maybe useful.
Adjustment of lifestyle should always be considered by depression or depressive symptoms. Lifestyle measures can sometimes be enough to cure depressive symptoms before a serious depression develop. Lifestyle adjustments can be:
- To slow down a stressful life with too much work or activities.
- Enough rest and sleep.
- A good diet with enough of necessary nutrients.
- Some physical exercise.
- Meditation.
- Supplement of vitamins, minerals, antioxidants, lecithin, amino acids and essential fatty acids.
- Stimulants like coffee or tea may help against depressive feelings in moderate amount. However, if you are a heavy user of these stimulants, you should cut down on your consumption.
There exist nutritional products in the marked to help against depressive symptoms. These contain ingredients that the brain uses as building blocks for neurotransmitters, for example amino acids and lecithin. They also often contain vitamins and minerals that the brain uses as tools to produce neurotransmitters, especially vitamin B6.
Supplements may further contain herbal extracts that trigger higher brain activity much like anti-depressive medications, but may have fewer side effects.