Edema—fluid accumulation and swelling—can occur in the body after eating too much salt, getting sunburnt, being stung by a bee, or walking in warm weather. It also can happen during pregnancy, after an injury, and as a side effect of certain medications (e.g., calcium channel blockers and estrogens). Or it can be an indicator of a much more serious condition, such as heart failure, blood clots, kidney disease, weak veins, liver problems, thyroid issues, or lymph node disorders (lymphedema). If left untreated, edema can worsen, causing pain, stiffness, difficulty moving, and decreased blood circulation. Typical treatment for edema (the symptom, not necessarily the underlying cause) involves elevating the affected body part(s), applying ice to the area, wearing compression stocking, reducing sodium intake, and taking a diuretic (also known as a water pill). Certain exercises (especially ones performed in water), therapeutic massage, and electrical stimulation also may be beneficial in reducing swelling and promoting fluid drainage. It is important to treat edema quickly to prevent tissue hardening and additional complications. Maintaining a proper body weight and standing or walking while traveling (as opposed to sitting for extended periods of time) can help to prevent the onset of edema.