ThiaminRepletion

Thiamin repletion refers to restoring body stores of thiamin (vitamin B1) in individuals with inadequate intake, malabsorption, increased losses, or heightened requirements. Thiamin is a water-soluble vitamin and a critical cofactor for enzymes involved in carbohydrate metabolism, including pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase, as well as for the transketolase reaction in the pentose phosphate pathway. Adequate thiamin is essential for energy production, particularly in tissues with high metabolic demand such as the brain and heart.

Deficiency can cause a range of conditions, most notably beriberi (dry with neuropathy and fatigue; wet with cardiac involvement) and Wernicke-Korsakoff syndrome, a neuropsychiatric disorder associated with acute thiamin shortage. At-risk populations include individuals with chronic alcoholism, malnutrition, malabsorption syndromes, post-bariatric surgery patients, and those on prolonged intravenous nutrition without adequate thiamin supplementation.

Repletion strategies emphasize prompt treatment when deficiency is suspected, as delays can lead to irreversible damage. In acute deficiency or suspected Wernicke’s, high-dose parenteral thiamin is typically used, such as 500 mg IV three times daily for 2–3 days, followed by 250 mg IV/IM daily for several days, then transition to oral supplementation. In stable patients, oral thiamin (for example, 100 mg daily or as dietary intake) may be sufficient. Thiamin should be given before or alongside glucose-containing fluids in at-risk individuals to prevent precipitating deficiency-related complications. Laboratory testing of thiamin status is not routinely used in acute care; clinical response guides management.

Prognosis improves with timely repletion, though some neurological deficits may persist if treatment is delayed. Safety is favorable, with rare hypersensitivity reactions to IV preparations.