Thiamine is specifically used in the treatment of the various manifestations of thiamine deficiency such as Beriberi and Wernick’s encephalopathy, neuritis associated with pregnancy, and pellagra. Supplementary Thiamine may be indicated prophylactically in conditions where there is low dietary intake or impaired gastrointestinal absorption of thiamine (e.g. alcohol) or where requirements are increased (pregnancy, carbohydrate-rich diet).
Thiamine, in the form of thiamine pyrophosphate, is the coenzyme for decarboxylation of α-ketoglutaric acid. Thiamine deficiency affects the peripheral nervous system, the gastrointestinal tract, and the cardiovascular system. This vitamin is necessary for the optimal growth of infants and children. Thiamine is not stored in the body and is regularly lost from tissues during short periods of deficiency. In order to maintain normal health, an adequate amount of thiamine is required every day. Deficiency of thiamine leads to fatigue, anorexia, gastrointestinal disturbance, tachycardia, irritability, and neurological symptoms. Beriberi, a disease due to vitamin B1 deficiency, is common in alcoholics, in pregnant women receiving an inadequate diet, and in people with malabsorption syndrome, prolonged diarrhea, and hepatic disease.
Thiamine is well absorbed from the gastrointestinal tract and widely distributed throughout the body. Thiamine is rapidly absorbed from the upper small intestine. Thiamine is not stored in the body to any appreciable extent. Excess ingested thiamine appears in the urine as intact thiamine or as pyrimidine, which arises from degradation of the thiamine molecule. The plasma half-life of thiamine is 24 hours.
Dosage & Administration
Mild chronic deficiency: 10 to 25 mg daily.
Severe deficiency: 200 to 300 mg daily.