Fluid Overload

Fluid overload means that there is too much fluid in the body. The increased level of fluid results in an excessive volume of fluid flowing around the circulatory system. This can overwork the heart and lead to heart failure. 

What are the symptoms?

If the total amount of fluid in the body is raised above normal, this increases the fluid circulating through the arteries and veins. Fluid can settle in the lungs (pulmonary oedema) causing breathlessness. The heart has to work harder to deal with all this fluid and this can result in heart failure. The symptoms of heart failure are breathlessness, tiredness, and swelling of the legs and feet.

Read more about the symptoms of fluid overload.

What are the causes?

The heart and kidneys act together to control the fluid content and sodium content in the body. If something goes wrong with this system (for example, heart failure or kidney damage), fluid overload can occur.

Another common cause is treatment with fluids administered through a vein. The fluids may be a mixture of chemicals and sterile water, nutrient solutions or blood. If too much fluid is administered, or the mixture of chemicals is imbalanced (too much sodium, for example) fluid overload can occur.

Learn more about the causes of fluid overload.

How is it diagnosed?

The features of fluid overload are very similar to those of other conditions, and these conditions need to be ruled out. They include lung and heart problems, circulatory disorders, liver disease and thyroid disease.

You will need heart tests, X-rays, blood tests and measurements of your fluid input and output (fluid balance).

What treatment is available?

Treatment of the underlying cause is important. The effects of fluid overload on the lung and heart also need treating. Separate leaflets are available on these topics.

Find out more about the treatment of fluid overload, pulmonary oedema and heart failure.

What is the outlook?

This depends on the cause. If you were fit and well before the problem occurred (for example, if you had too much fluid after a routine operation), you stand a good chance of recovery. If your fluid overload was due to heart or kidney problems, the outlook (prognosis) depends on how easily the underlying condition responds to treatment.

Did you find this information useful?

Thanks for your feedback!

Why not subcribe to the newsletter?

We would love to hear your feedback!

  • Kim IY, Kim JH, Lee DW, et al; Fluid overload and survival in critically ill patients with acute kidney injury receiving continuous renal replacement therapy. PLoS One. 2017 Feb 14 12(2):e0172137. doi: 10.1371/journal.pone.0172137. eCollection 2017.
  • Byrne L, Van Haren F; Fluid resuscitation in human sepsis: Time to rewrite history? Ann Intensive Care. 2017 Dec 7(1):4. doi: 10.1186/s13613-016-0231-8. Epub 2017 Jan 3.
  • Glatz T, Kulemann B, Marjanovic G, et al; Postoperative fluid overload is a risk factor for adverse surgical outcome in patients undergoing esophagectomy for esophageal cancer: a retrospective study in 335 patients. BMC Surg. 2017 Jan 13 17(1):6. doi: 10.1186/s12893-016-0203-9.
Dr Laurence Knott
Peer Reviewer:
Dr Adrian Bonsall
Document ID:
29443 (v1)
Last Checked:
09 July 2017
Next Review:
08 July 2020

Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. Patient Platform Limited has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.