OVERVIEW: What every practitioner needs to know

Are you sure your patient has Refeeding syndrome? What are the typical findings for this disease?

Refeeding syndrome is a state of fluid and electrolyte imbalances that can lead to organ dysfunction upon the reintroduction of feeds after a prolonged state of malnutrition. It is a serious condition that has the potential to be lethal.

Refeeding syndrome was first identified during wartimes, especially with Japanese prisoners during World War II.

The typical findings in Refeeding syndrome include fluid and electrolyte imbalances, mainly hypophosphatemia, hypokalemia, hypomagnesia, and hypoglycemia. The imbalance of electrolytes is the main cause of symptoms which commonly include:

Continue Reading

  • Fluid overload

  • Dehydration

  • Weakness, Paresthesias

  • Vitamin deficiencies

What other disease/condition shares some of these symptoms?




Diabetic Ketoacidosis

What caused this disease to develop at this time?

Refeeding syndrome is found in those who undergo reinstitution of enteral or parenteral feeds after a prolonged period of malnutrition or anorexia. The reintroduction of feeds can cause fluid and electrolyte imbalances that can lead to cardiac complications.

The most common electrolyte abnormalities are hypophosphatemia, hypokalemia, and hypomagnesia. There can also be hypoglycemia, as well as vitamin deficiencies. The most common vitamin deficiency is thiamine.

Upon restarting feeds, the patient will often have muscle weakness, fatigue, and dehydration.

Epidemiologic studies are lacking, in part, due to the absence of accepted diagnostic criteria or internationally agreed upon guidelines for diagnosis. Most published data from prospective and retrospective case series do not reflect overall incidence.

What laboratory studies should you request to help confirm the diagnosis? How should you interpret the results?

  • Basic Metaboic Panel, Mg, Phos should be ordered daily to monitor depletion of these electrolytes.

  • Vitamin levels should be ordered initially to determine deficiencies.

Would imaging studies be helpful? If so, which ones?

No imaging is needed to diagnose this condition.

If you are able to confirm that the patient has Refeeding syndrome, what treatment should be initiated?

  • If a patient has a prolonged state of fasting, rehydration is necessary with IV fluids.

  • The type of refeeding, whether it is parenteral or enteral, is dependent upon the state of malnutrition.

  • Reintroduction of enteral or parenteral feeds must be done slowly. The main goal is to provide slow calorie repletion, especially during the first week of refeeding. Initial feeding may begin with 20 kcal/kg of body weight per day.

  • During the initial phase, daily monitoring of the BMP, Mg, P levels every day is necessary to monitor electrolyte shifts. Electrolyte replacement is necessary for significant abnormalities to prevent organ dysfunction.

  • Fluid balance must be closely monitored by meticulously measuring the patient’s total intake and output.

  • Multivitamins should be given and additional thiamine should be provided on its own.

  • Counseling is necessary for those with eating disorders, as these patients can have recurrence of their malnutrition, especially with anorexia nervosa.

What are the adverse effects associated with each treatment option?

Fluid overload can impair cardiac contractility. Cardiac contractility can be further impaired if there is severe hypokalemia, hypomagnesia or hypophosphatemia.

With the reintroduction of enteral feeds, there is a risk of increased stool output.

What are the possible outcomes of Refeeding syndrome?

Prognosis is good. The highest risk of refeeding occurs in the initial stages and this is where most of the complications from electrolyte imbalances can occur.

The benefit of treatment is to provide nutrition and obtain a safe weight gain in a monitored setting.

What causes this disease and how frequent is it?

Refeeding syndrome is caused by the rapid introduction of feeds or fluids that causes an intracellular shift of phosphate, potassium and magnesium leading to low serum levels. These low levels cause individuals to be symptomatic in regards to impaired cardiac function, fluid overload, and edema. If these imbalances aren’t properly corrected or prevented, it can result in death.

There is an unclear incidence in the pediatric population. This may be due to the fact that there is no strict definition of the syndrome or that it is often unrecognized. This is also the reason this area is lacking in epidemiological studies.

Predisposing individuals include those who are exposed to famine in war-torn countries suffering from Marasmus or Kwashiorkor, those suffering from anorexia nervosa, those undergoing chemotherapy, or even children of neglect.

How do these pathogens/genes/exposures cause the disease?

In a prolonged state of starvation, there will be a decreased amount of insulin produced, which, in turn, will cause an increase in glucagon production. There will also be an increase in gluconeogenesis. This causes an increase in glucose production from the breakdown of lipids and protein. Therefore, the major source for the body’s fuel comes from ketones and fatty acids.

During refeeding, there is increased carbohydrate metabolism, which also increases glucose. However, the increase in glucose stimulates the pancreas to release more insulin. Because there is a higher level of insulin, there is now an intracellular shift of phosphate, potassium and magnesium leading to low serum values. The low serum values of the electrolytes leads to muscle weakness, cardiac arrhythmias, and even changes in mentation.

Other clinical manifestations that might help with diagnosis and management

Thiamine deficiency is the most common vitamin deficiency found during refeeding. This occurs especially with carbohydrate feeds due to intracellular thiamine being used up. Thiamine is an important cofactor for many enzymatic pathways.

Thiamine deficiencies can lead to Wernicke’s encephalopathy, which can result in visual disturbances and changes in mental status.

What complications might you expect from the disease or from the treatment of the disease?


  • muscle weakness, including diaphragmatic weakness leading to respiratory failure

  • paresthesia

  • acute encephalopathy

  • decreased cardiac contractility

  • osteomalacia


  • cardiac arrhythmias

  • hypotension

  • ileus

  • muscle weakness and paresthesia

  • hypotonia

  • glucose intolerance


  • cardiac arrhythmias (i.e. Torsades de Pointes)

  • muscular weakness, paresthesia

  • ataxia

  • change in mental status

  • tetany

Thiamine deficiency

  • Wernicke’s encephalopathy

  • visual disturbances

  • change in mental status

Fluid overload with rehydration leading to increased cardiac work load.

Are additional laboratory studies available; even some that are not widely available?

There are no additional laboratory studies available in diagnosing refeeding syndrome.

How can Refeeding syndrome be prevented?

Enteral or parenteral feeds must be reintroduced slowly. The main goal is to provide slow calorie repletion, especially during the first week of refeeding. At first, 20 kcal/kg of body weight per day should be provided.

During the initial phase, check a BMP, Mg, P level every day to monitor electrolytes. If the levels are extremely low and patients are symptomatic, electrolytes should be replaced.

Close monitoring of fluid balance by checking ins and outs frequently.

Multivitamins should be given, but thiamine should be provided on its own.

It is important to monitor vital signs, as these patients can develop tachycardia or decreased respiratory rate if electrolytes are low.

Because of the potential for serious cardiac arrhythmias, a baseline EKG should be obtained followed by serial EKG’s during treatment.

Each person undergoing refeeding after a prolonged state of malnutrition should have nutrition services consultation to provide patient education.

If the prolonged fasting state is due to a anorexia, a psychologist should be part of the interdisciplinary team.

What is the evidence?

Crook, MA, Hally, V, Panteli, JV. “The importance of the refeeding syndrome”. Nutrition. vol. 17. 2001. pp. 632-7.

Khan, LUR, Ahmen, J, Khan, S, MacFie, J. “Refeeding Syndrome: A Literature Review”. Gastroenterology Research and Practice. vol. Vol 2011.

Marinella, MA. “Refeeding Syndrome and Hypophosphatemia”. J Intensive Care Med. vol. 20. 2005. pp. 155

Fuentebella, J, Kerner, JA. “Refeeding Syndrome”. Pediatric Clinics on North America. vol. 56. 2009. pp. 1201-10.

Ongoing controversies regarding etiology, diagnosis, treatment