From the Guidelines
The recommended injectable thiamine dosage is 200 mg, 3 times a day, IV in cases of high suspicion or proven deficiency, as stated in the 2022 espen micronutrient guideline 1.
Key Considerations
- The dosage of thiamine varies based on the clinical situation, with different recommendations for mild deficiency, chronic diuretic therapy, and high suspicion or proven deficiency.
- For patients with encephalopathy of uncertain etiology, including Wernicke encephalopathy, a dose of 500 mg, 3 times a day, IV is recommended 1.
- In cases of refeeding syndrome, 300 mg IV before initiating nutrition therapy, followed by 200-300 mg IV daily for at least 3 more days is suggested 1.
Administration Route
- The oral route is adequate in cases of suspicion of chronic deficiency without any acute disease, while the IV route is preferred in cases of acute disease or suspicion of inadequate intake, even short term 1.
Clinical Context
- The administration of thiamine should be prescribed without hesitation from admission for 3-4 days in patients admitted to emergency or intensive care, with a dose of 100-300 mg/day IV 2.
- 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 2.
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 (see WARNINGS). In the treatment of beriberi, 10 to 20 mg of thiamine hydrochloride are given IM three times daily for as long as two weeks. Patients with neuritis of pregnancy in whom vomiting is severe enough to preclude adequate oral therapy should receive 5 to 10 mg of thiamine hydrochloride IM daily. 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.
The recommended dosage of thiamine injection is:
- 10 to 20 mg IM three times daily for the treatment of beriberi
- 5 to 10 mg IM daily for patients with neuritis of pregnancy
- 50 to 100 mg IM daily for the treatment of Wernicke-Korsakoff syndrome 3
From the Research
Thiamine Dosage
- The optimal thiamine dose for treating or preventing Wernicke's encephalopathy or Wernicke-Korsakoff syndrome is not clearly established, as a study found no significant differences between different dosage conditions 4.
- The study compared parenteral thiamine doses of 100mg daily, 100mg thrice daily, and 300mg thrice daily for 3 days in asymptomatic at-risk patients, and 100mg thrice daily, 300mg thrice daily, and 500mg thrice daily for 5 days in symptomatic patients 4.
- High-dose thiamine replacement is suggested for neuropsychiatric syndromes associated with thiamine deficiency, including Wernicke-Korsakoff syndrome, alcoholic cerebellar syndrome, and alcoholic peripheral neuropathy 5.
- Treatment of Wernicke-Korsakoff syndrome is based on the administration of thiamine, which should be started early and parenterally at the appropriate doses, without waiting to confirm the diagnosis 6.
Administration and Timing
- Thiamine administration should be started early in patients with compatible symptoms, and parenteral administration is recommended 6.
- The duration of thiamine treatment can vary, with one study administering thiamine for 3 days in asymptomatic at-risk patients and 5 days in symptomatic patients 4.
Considerations
- The absence of conclusive evidence for the superiority of high-dose thiamine supports a recommendation for patient-specific treatment, considering other biochemical factors such as magnesium and other B vitamin deficiencies 4.
- Thiamine deficiency can lead to impaired energy metabolism, oxidative stress, and neurodegeneration, highlighting the importance of early treatment and consideration of other therapeutic possibilities 7.