Cause of edema can be a mechanical obstacle that prevents the lymph and venous blood flow from tissues. When pressure on the limb above the vein can be suganami and deeper located artery will continue to deliver blood tissues. Because of these conditions, the blood which has entered the tissue will not be able to come out and begin to accumulate between the fibers and cells. Another reason is the change of structure of lymph or blood and damage blood vessel walls. In this regard, the blood seeps through capillary walls.

Edema may be caused by disorders of the nervous system. They are called "nerve swelling" and develop after paralysis from different lesions of the spinal cord or brain.

Swelling in the hands can occur when injuries, trauma, but most often this phenomenon occurs when a person is tired or sleep deprived. Also swellings appear the abuse of alcohol, with the unhealthy lifestyle, if there is high load on the wrist in an awkward position during sleep.

If your hands swell in the heat only, then the cause may be vascular-lymphatic nature. In the heat of the liquid is poorly excreted from the body, which leads to deterioration of the outflow of lymph and to its stagnation. This often occurs in women during pregnancy due to hormonal changes.

Swelling of the hands are rarely found separately, they often appear along with swelling of other body parts. Also, the cause may be kidney disease, heart, liver, as in diseases of these organs excess fluid accumulates in the body. It is also possible to increase body mass.

Large swelling may be a symptom of a serious illness – limpidly. This disease does not occur with the necessary flow of lymph through the lymphatic vessels swelling appeared not only persist, but also causes discoloration of the skin.