There are several differant types of edema. I'm assuming you are asking about Extracelluar.
When there is volume excess or fluid overload, the fluid pressure is greater than the oncotic pressure in the vessels. Fluid is then pushed into the tissue spaces, and peripheral edema results. This you can see. Weight gain, puffy eyelids, etc. occur.
Diuretics (Lasix, Aldactone, HCTZ) are given. Of course, Potassium needs to be taken if Lasix is given since Lasix will deplete your potassium levels.
Low Sodium Diet
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