Refeeding Syndrome – Symptoms, Causes, Diagnosis, Treatment Guidelines

What is Refeeding Syndrome?

When individuals have gone through long periods of malnourishment or starvation, they are at risk for developing refeeding syndrome once they resume feeding. This condition covers varied symptoms of fluid and electrolyte imbalances within the body. Such symptoms may lead to life-threatening complications, such as heart failure and even death, if left untreated. Thus, individuals who have been through eating disorders should be well monitored once they reform their eating habits.

Refeeding Syndrome Picture

What are the Symptoms of Refeeding Syndrome?

Symptoms of this condition include those functions on which potassium, phosphorus, and magnesium have direct influence. On the one hand, potassium helps control cardiac functions, regulate blood pressure, and facilitates conduction of impulses along nerves. Phosphorus, on the other hand, is an important electrolyte for bone and teeth formation and activation of different Vitamin B complexes and enzymes. Magnesium is beneficial in stimulating brain activity and in increasing bone mineral density. Hypokalemia (deficiency in potassium) can cause:

  • Ileus
  • Cardiac arrest
  • Heart problems
  • Paralysis
  • Respiratory depression

Hypophosphatemia (abnormally low level of phosphorus) can lead to:

  • Cardiac heart failure
  • Confusion
  • Seizures
  • Bone problems

Hypomagnesemia (abnormally low level of magnesium) can result in:

  • Tachycardia
  • Diarrhea
  • Hypocalcemia (low level of calcium)

Other general symptoms include:

  • Fluid retention
  • Abrupt weight gain
  • Alterations of serum sodium levels
  • Increase in vital signs
  • Impaired mental status
  • Hyperglycemia or insulin resistance

What Causes Refeeding Syndrome?

When one’s body is allowed to starve for long periods, the body then gets energy by using up its reserved protein and body fat. At the time of refeeding, where carbohydrates are introduced again to the system, the tissues then resume to their normal process of producing energy by breaking down glucose.

However, the sudden increase in glucose triggers a chain reaction, causing the position of magnesium, phosphorus, and potassium to shift from outside to inside cells. Serum levels of such electrolytes begin to drop abruptly and may trigger different complications, both mild and life-threatening.

Individuals who are at risk for developing this syndrome are those who resume eating after suffering from severe malnutrition, anorexia nervosa, diabetic ketoacidosis, and chronic gastrointestinal disease such as neurological dysphagia and cancer. Alcoholics and obese patients who have undergone extensive weight loss are also more likely to develop this condition.

How to Diagnose Refeeding Syndrome?

This condition often goes underdiagnosed until visible signs and symptoms begin to appear. Skilled medical practitioners are able to detect it ahead of time if they have already gained awareness and familiarity of the disease. Diagnosis is often done through diagnostic and laboratory exams that have been realized, and the presence of refeeding syndrome is confirmed when there is a significant plunge in the serum levels of phosphorus, potassium, and magnesium.

How to Treat Refeeding Syndrome?

Treatment plans for this condition should begin with proper attention to patients who have the potential of developing the said condition. Health care providers should remember that refeeding should be done with precaution. There are different established guidelines medical practitioners can refer to when dealing with patients that have the tendency of developing such state.

The syndrome is expected to lower levels of important minerals; thus vitamin replacement should be of importance in addressing the syndrome. It should be started immediately and may last for at least 10 days. The important electrolytes may also be substituted using different routes such as oral, enteral, or parenteral, depending on which strategy can possibly be utilized.

Vitamin replacement should also be supplemented with rigorous monitoring of nutritional status. Electrolyte levels should be checked regularly through blood chemistry and urinalysis.

NICE Treatment guidelines for refeeding Syndrome


Cases of refeeding syndrome often have good prognosis once detected at its initial stages. When proper management and precautions are employed, development of complications is prevented. However, when it is left unnoticed, it can be fatal to one’s health status.

Sudden drop in vital minerals can pose life-threatening symptoms to a patient suffering from refeeding syndrome, and it can potentially be irreversible.

Life Expectancy

The survival chances of refeeding syndrome patients may depend on how immediate interventions are done to address the condition. Patients who are managed early are able to surpass the condition and may resume to normal living as soon as mineral levels are stabilized.

However, it can be deadly if left unnoticed and unattended for a prolonged duration since it can cause cardiovascular and respiratory problems and eventual death.


Although this condition is also referred as a complication to many eating disorders, it can also cause subsequent complications. Such complications can be categorized in four clusters:

  • Electrolye imbalances ( hypophosphatemia, hypokalemia, and hypomagnesemia)
  • Gastrointestinal impairment (bloating or the perception of being full resulting from constipation, abdominal cramps, and delayed emptying of gastric contents)
  • Water retention (edema)
  • Cardiac and respiratory complications


This condition is actually best addressed through prevention. Necessary precautions should be done prior to refeeding of patients who have suffered long periods of starvation or fasting. Initial intake of food should be kept at a minimal and must be stabilized first before resuming to his/her preferred and recommended diet.

Daily monitoring of fluid and electrolyte levels should also be a top priority to immediately recognize any developing complications of refeeding syndrome.

Further reading references

Let us know new points via comments from you if we missed anything here. 

5 thoughts on “Refeeding Syndrome – Symptoms, Causes, Diagnosis, Treatment Guidelines

  • 07/12/2012 at 9:04 AM

    I never thought refeeding syndrome can happen since I have not been exposed to this case with my experience as a nurse. My question is, will refeeding syndrome lead to hyperglycemia as well since the body is used to not producing insulin because of starvation? Because once the person resumes feeding again, the pancreas may not be able to produce the required insulin since it has been dormant during starvation. Thank you for your correspondence.

  • 08/12/2012 at 4:26 PM

    Hi! I have been dieting because I wanted to lose weight. I usually eat only at most 700 calories per day. In case I go back to my usual diet pattern, which is 1,800 calories in a day, will I experience refeeding syndrome too? Or this just applies for those who reached a malnourished state? Thanks

  • 07/09/2017 at 11:35 PM

    I’m wondering if this happened to my mother. She suffered a traumatic heart attack and was ventilated for a total of 5 or 6 days where she did not have nutrition. Once off the ventilator, she was given a feeding tube. She is out of hospital and vitals are ok but her short term memory is terrible. Her magnesium and potassium levels were low but not sure about phosphate. Neurologists diagnosed her with Karsokoff Syndrome but wondering if it is a thiamine deficiency from refeeding? How do we tell and what kind of doctor treats this? Thank you!

  • 08/02/2018 at 10:25 AM

    Very helpful post!! Followed you over here from Mugwump. Being from India I have never needed such knowledge, but you never know when things will change. Dental Hospital in Hyderabad


Leave a Reply

Your email address will not be published. Required fields are marked *