1. Heart Disease (Coronary Artery Disease) Slideshow Pictures
2. Atrial Fibrillation Slideshow: Causes, Tests and Treatment
3. Take the Heart Disease Quiz!

Medical Author:

John P. Cunha, DO, FACOEP

John P. Cunha, DO, FACOEP

John P. Cunha, DO, is a U.S. board-certified Emergency Medicine Physician. Dr. Cunha's educational background includes a BS in Biology from Rutgers, the State University of New Jersey, and a DO from the Kansas City University of Medicine and Biosciences in Kansas City, MO. He completed residency training in Emergency Medicine at Newark Beth Israel Medical Center in Newark, New Jersey.

View Full Profile

Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

View Full Profile

In this Article

• What is edema?
• What is pitting edema and how does it differ from non-pitting edema?
• What causes pitting edema?
• How does salt intake affect edema?
• Why does a patient with heart disease retain fluid?
• Why do patients with liver disease develop ascites and edema?
• Why does edema occur in patients with kidney disease?
• What is idiopathic edema?
• How does venous insufficiency cause edema?
• Which diuretics are used to treat edema?
• Are diuretics used for other purposes?
• Edema At A Glance
• Patient Comments: Edema - Symptoms
• Patient Comments: Edema - Salt Intake
• Patient Comments: Edema - Diuretics
• Patient Comments: Edema - Pitting Edema Causes
• Patient Comments: Edema - Causes
• Patient Comments: Edema - Effective Treatments
• Find a local Internist in your town
• Edema Index

Diuretics have several other uses in addition treating edema.

• A diuretic may be used as part of the treatment program for patients with hypertension. (High blood pressure may be caused by salt retention, or caused by some antihypertensive medications). In fact, most medications that dilate the blood vessels and reduce blood pressure, except for ACE inhibitors and angiotensin receptor blockers, lead to secondary salt retention by the kidneys.
  
  
• Thiazide diuretics also have been used to prevent the formation of kidney stones. These drugs reduce the urinary excretion of calcium, which is a component of the kidney stone.
  
  
• Acetazolamide (Diamox) taken a few days before going to high altitudes, appears to reduce the tendency for people to develop altitude sickness.

• Edema is a swelling, usually of the legs, due to the accumulation of excessive fluid in the tissues.
  
  
• The edema that occurs in diseases of the heart, liver, and kidneys is mainly caused by salt retention, which holds the excess fluid in the body.
  
  
• In certain liver and kidney diseases, low levels of albumin in the blood can contribute to fluid retention.
  
  
• Heart failure, cirrhosis of the liver, and a kidney disease called nephrotic syndrome are the most common systemic diseases that cause edema.
  
  
• Excess fluid that accumulates in the lungs is called pulmonary edema.
  
  
• Excess fluid that accumulates in the abdominal cavity is called ascites.
  
  
• Edema of unknown cause occurs primarily in women.
  
  
• Varicose veins or thrombophlebitis (a blood clot in an inflamed vein) of the deep veins in the legs causes edema that is localized to the legs.
  
  
• Therapy for edema consists of treating the underlying conditions, restricting salt intake, and often using diuretics (medicines to induce urination).

Reference: Harrison's Principles of Internal Medicine, McGraw-Hill, edited by Eugene Braunwald, et. al., 2001

Previous contributing authors and editors:

Medical Author: Mark Scott Noah, MD
Medical Editor: Leslie J. Schoenfield, MD, PhD