Do diuretic drugs relieve the symptoms of fluid overload?

Diuretic drugs relieve symptoms of acute decompensated heart failure.  These may include dyspnea due to excess water within the lungs (pulmonary edema) and peripheral edema (excess fluid accumulation within the skin tissues).  These two are prime examples of how diuretics relieve the symptoms of fluid overload within a heart failure patient.  It is important to note, however, that while symptoms decrease with diuretics, patients may not live longer secondary to their use.  It is important to combine diuretic therapy with other heart failure therapies as prescribed by a physician in order to improve one's length of life along with quality of life.

To an extent, yes they do. However, as congestive heart failure advances those medications are less and less effective and can even begin to affect the kidney function. At that point in time a therapy called Ultrafiltration is usually accessed to pull fluid off of the body slowly over the period of 2-3 days. A person can lose a massive amount of fluid via this therapy and feel better. Ultrafiltration is usually reserved for those patients who are responding to diuretics less and less as heart failure advances to the later stages.