What is the preferred route of administration, intravenous (IV) or oral, for thiamine supplementation in the prevention of refeeding syndrome?

From the Guidelines

For refeeding syndrome, intravenous (IV) thiamine is preferred over oral administration in high-risk patients, with a recommended dose of 300 mg IV before initiating nutrition therapy, followed by 200-300 mg IV daily for at least 3 more days, as stated in the espen micronutrient guideline 1. This approach is supported by the most recent and highest quality study, which emphasizes the importance of rapid achievement of higher blood levels of thiamine in malnourished patients to prevent Wernicke's encephalopathy or cardiac complications. The use of IV thiamine is particularly crucial in patients with severe malnutrition, as it bypasses potentially impaired intestinal absorption and ensures rapid replenishment of thiamine stores. Additionally, comprehensive refeeding management should include slow introduction of calories, correction of electrolytes (particularly phosphate, potassium, and magnesium), and close monitoring of fluid balance, as recommended in the espen practical guideline: clinical nutrition in cancer 1. Some key points to consider in refeeding syndrome management include:

• Monitoring for rare allergic reactions, especially with the first dose of IV thiamine
• Administering thiamine before any carbohydrate administration to prevent precipitating acute thiamine deficiency
• Providing a balanced micronutrient mixture, including vitamin B1, and monitoring electrolyte levels, as suggested in the espen guidelines on nutrition in cancer patients 1
• Gradually increasing nutrition over several days to prevent refeeding syndrome, as recommended in the espen practical guideline: clinical nutrition in cancer 1. It is essential to prioritize the patient's nutritional status and overall health, and to consult the most recent and highest quality guidelines, such as the espen micronutrient guideline 1, to ensure optimal management of refeeding syndrome.

From the FDA Drug Label

Dosage and Administration “Wet” beriberi with myocardial failure must be treated as an emergency cardiac condition, and thiamine must be administered slowly by the IV route in this situation In the treatment of Wernicke-Korsakoff syndrome, thiamine hydrochloride has been administered IV in an initial dose of 100 mg, followed by IM doses of 50 to 100 mg daily until the patient is consuming a regular, balanced diet. Patients with marginal thiamine status to whom dextrose is being administered should receive 100 mg thiamine hydrochloride in each of the first few liters of IV fluid to avoid precipitating heart failure. An oral therapeutic multivitamin preparation containing 5 to 10 mg thiamine, administered daily for one month, is recommended to achieve body tissue saturation.

For refeeding syndrome supplementation, IV thiamine is recommended in certain situations, such as:

• Wet beriberi with myocardial failure
• Wernicke-Korsakoff syndrome with an initial dose of 100 mg IV
• Patients with marginal thiamine status receiving dextrose IV to avoid precipitating heart failure Oral thiamine may be sufficient for mild cases or for maintenance therapy, such as:
• Mild infantile beriberi
• Body tissue saturation with an oral therapeutic multivitamin preparation containing 5 to 10 mg thiamine daily for one month 2

From the Research

IV versus Oral Thiamine for Refeeding Syndrome Supplementation

• The studies provided do not directly compare IV versus oral thiamine for refeeding syndrome supplementation 3, 4, 5, 6, 7.
• However, the studies emphasize the importance of thiamine supplementation in preventing and treating refeeding syndrome, particularly in malnourished patients 3, 4, 5.
• Thiamine deficiency is a significant risk factor for refeeding syndrome, and supplementation is crucial to prevent complications such as Wernicke's encephalopathy and Korsakoff psychosis 4.
• The route of thiamine administration (IV or oral) is not specified in the studies, but it is essential to ensure that patients receive adequate thiamine supplementation to prevent refeeding syndrome 3, 5.
• The studies highlight the importance of careful patient monitoring, multidisciplinary nutrition team management, and gradual increase in calorie intake to prevent refeeding syndrome 4, 5, 6, 7.
• Electrolyte abnormalities, such as hypophosphatemia, hypomagnesemia, and hypokalaemia, are common in refeeding syndrome, and thiamine supplementation is often provided in conjunction with electrolyte replacement therapy 3, 4, 5, 6.