From the Guidelines
For patients with malnutrition, the recommended thiamine (Vitamin B1) dose is 3 x 100-300 mg per day intravenously, as this route is the most efficient in providing the necessary amounts to alleviate acute deficiency symptoms. This recommendation is based on the most recent and highest quality study available, which suggests that thiamine can be administered orally, enterally, or IV, but the IV route is preferred due to its efficiency 1. The study also notes that thiamine is well absorbed, except in cases of alcohol-related gastritis.
Key Considerations
- Thiamine deficiency can lead to severe health complications, including beriberi and Wernicke-Korsakoff syndrome, making prompt replacement crucial in malnourished patients.
- The IV route is preferred due to its efficiency in providing the necessary amounts to alleviate acute deficiency symptoms.
- Thiamine should be administered before any carbohydrate-containing solutions to prevent precipitating or worsening Wernicke's encephalopathy.
- Side effects are rare, making aggressive replacement safe when deficiency is suspected.
Administration Guidelines
- In patients admitted to emergency or intensive care, thiamine (100-300 mg/day IV) should be prescribed without hesitation from admission for 3-4 days 1.
- In patients admitted on the ward with any suspicion of reduced food intake during the previous days or high alcohol consumption, thiamine 100-300 mg/day should be administered by either oral or IV route 1.
From the FDA Drug Label
DOSAGE AND ADMINISTRATION: ... An oral therapeutic multivitamin preparation containing 5 mg to 10 mg thiamine, administered daily for one month, is recommended to achieve body tissue saturation. The recommended thiamine dose in cases of malnutrition is 5 mg to 10 mg daily for one month, as part of an oral therapeutic multivitamin preparation, to achieve body tissue saturation 2.
From the Research
Thiamine Dosage in Malnutrition
The recommended thiamine dose in cases of malnutrition varies depending on the severity of the condition and the presence of Wernicke's encephalopathy.
- In patients with established Wernicke's encephalopathy, parenteral thiamine 200-500mg three times a day should be given for 3-5 days, followed by oral thiamine 250-1000mg/day 3.
- In patients with suspected Wernicke's encephalopathy, parenteral thiamine 250-300mg should be given two times a day for 3-5 days, followed by oral thiamine 250-300mg/day 3.
- In patients at high risk of thiamine deficiency, parenteral thiamine 250-500mg/day should be given for 3-5 days, followed by oral thiamine 250-300mg/day 3.
- In patients with malnutrition, thiamin replacement should be given before starting nutrition to prevent re-feeding syndrome, with a dose of 200 mg/day, i.v. 4.
- Oral thiamine supplementation of 100 to 800 mg per day for 6 months may be required to aid recovery in patients with Wernicke's encephalopathy 5.
General Recommendations
- Oral thiamine substitution with at least 50 mg per day and supply of a sufficient and complete diet should be given to any person that might be at risk for thiamine deficiency 6.
- Any patient suspicious for acute thiamine deficiency needs to be treated under inpatient conditions and there needs to receive 50 to 100 mg thiamine intravenously 3 to 4 times a day 6.