Diuretics thiamine deficiency

Individuals on long-term diuretic therapy may also experience elevated levels of homocysteine, an amino acid regulated by folate. High homocysteine levels increase the risk of heart disease. Thiamin, or vitamin Bj, depletion is another possible side effect of loop diuretics. Individuals with thiamin deficiencies are at risk for fatigue, heart enlargement, muscle cramps, heart rate irregularities, and impaired mental function. 

Thiamin that is not bound to plasma proteins is rapidly filtered at the glomerulus. Diuresis increases the excretion of the vitamin, and patients who are treated with diuretics are potentially at risk of thiamin deficiency. Some of the diuretics used in the treatment of hypertension may also inhibit cardiac (and other tissue) uptake of thiamin, thus further impairing thiamin status, which may be a factor in the etiology of heart failure (Suter and Vetter, 2000). 

Loop or high-ceiling diuretics causes a vasodilatory effect and increase renal blood flow before diuresis. The most common side effects are fluid and electrolyte imbalances such as hypokalemia, hyponatremia, hypocalcemia, hypomagnesemia, and hypochloremia. Hypochloremic metabolic alkalosis may result. Orthostatic hypotension can also occur. Thrombocytopenia, skin disturbances, and transient deafness are seen rarely. Prolonged use can cause thiamine deficiency. 

Suter, P.M., Haller, J., Hany, A., and Vetter, W., 2000. Diuretic use a risk for subclinical thiamine deficiency in elderly patients. The Journal of Nutrition, Health Aging. 4 69 71. 

Severe multisystem trauma, endotoxemia, or situations in which there is a raised metabolic demand for thiamin, such as pregnancy, thyrotoxicosis, and intercurrent illness or impaired absorption (e.g., alcohol abuse or gastrointestinal disease or resection), can produce subclinical evidence of thiamin deficiency or more severe life-threatening aspects of beriberi, such as renal and/or cardiovascular failure. The elderly may be particularly at risk of subclinical thiamin deficiency. One Belgian study on patients with a mean age of 83 years reported that 40% had a raised TDP effect (>15%), in whom there was a high proportion of Alzheimer s disease, depression, cardiac failure, and falls. The diuretic furosemide was also more frequently taken by the thiamin-deficient patients. 

Alcohol is an important factor in causing thiamin deficiency because it inhibits the active transport of thiamin across the gut and when abused it impairs the quality of the diet consumed. Diuretics accelerate the excretion of thiamin and appear to override the renal conservation mechanism. Their use is of potential concern in elderly people whose diet may be poor for other medical reasons and their physicians may be unaware of their need for supplemental nutrient. 

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