What are some possible causes of edema?

Several causes: Edema is fluid in one's tissues (usually the skin) that is outside of one's blood vessels, lymph vessels, and cells. The fluid is "in between" cells and leaked out of the person's blood vessels or lymph vessels. Poor circulation, obstructed veins, standing or sitting too long, thyroid disease, kidney disease, low protein levels, etc., can cause edema (most often noticeable in the legs).

Many possibilities: Some causes of swelling include systemic problems such as hypertension, and problems with the kidneys and localized issues such as arthritis, infection, lymphatic obstruction, blood clots, varicose veins, trauma (fracture, sprain, tendonitis) and side effects to medication. Have it evaluated by a professional and get the appropriate treatment.