When you visit a hospital with generalized edema, you can register for nephrology, cardiology, and endocrinology, because the most frequent causes are heart disease, kidney disease, and thyroid disease. Heart disease is mostly seen in heart failure, and edema is obvious after activity and may be accompanied by chest tightness, breathlessness, and inability to lie down at night. The edema can be reduced with the treatment of cardiac and diuretic drugs. If it is caused by kidney disease, it can be seen in nephrotic syndrome and renal failure. Nephrotic syndrome is mostly seen with large amount of foamy urine and hypoalbuminemia, and the disease can be normalized by applying immunosuppressive drugs. If the disease is caused by renal failure, it may be accompanied by oliguria or anuria and requires active renal replacement therapy. If caused by abnormal thyroid function, such as hyperthyroidism or hypothyroidism, thyroid hormone replacement therapy needs to be applied.