At 7 weeks, homozygous KO and KI mice on a standard diet had lower blood thiamine levels than WT mice (0.796±0.259 μM), at 0.058±0.051 and 0.126±0.092 μM, respectively. Days 5 and 14 saw a significant decrease in blood thiamine concentrations to 0.010 in WT and homozygous KO and KI mice fed a thiamine-restricted diet (thiamine: 0.60 mg/100 g of chow). 0.010±0.006 and ±0.009 μM. mice of WT (0.609±0.288 μM). In WT mice given a typical diet, the brain homogenates had a thiamine concentration of 3.81±2.18 nmol/g wet weight, while KO and KI brain homogenates had thiamine values of 1.33±0.96 and 2.16±1.55 nmol/g wet weight, respectively. Notably, following 5 days (0.95±0.72 nmol/g wet weight) and 14 days (1.11±0.24) of eating a thiamine-restricted diet (thiamine: 0.60 mg/100 g food), the KO and KI were reduced. In comparison to WT (3.65 ± 1.02 nmol/g wet weight), thiamine concentrations in mouse brain homogenates gradually drop before the mice exhibit illness symptoms [2].

On a typical diet containing 1.71 mg/100 g of thiamine, WT, homozygous and heterozygous KO, and KI mice survived for over six months without exhibiting any signs of disease. After being fed a diet restricted in thiamine (thiamine: 0.60 mg/100 g chow), homozygous KO and KI mice showed signs of paralysis, weight loss, and immobility, respectively. These mice died after 12 and 30 days, respectively. Likewise, within 14 and 18 days, respectively, homozygous KO and KI mice that were fed a diet restricted in thiamine and had a reduced thiamine percentage (thiamine: 0.27 mg/100 g of food) perished. Nevertheless, mice administered a thiamine-restricted diet (thiamine: 0.60 mg or 0.27 mg/100g of chow) in both WT and heterozygous KO and KI groups survived for over 6 months without exhibiting any signs of sickness [2].

Absorption, Distribution and Excretion
Absorption of thiamin occurs mainly in the jejunum. At low concentrations of thiamin, absorption occurs by an active transport system that involves phosphyrylation; at higher concentrations, absorption occurs by passive diffusion. Only a small percentage of a high dose of thiamin is absorbed, and elevated serum values result in active urinary excretion of the vitamin.
Thiamin is transported in blood in both erythrocytes and plasma and is excreted in the urine.
Thiamine is absorbed from the small intestine and is phosphorylated in the intestinal mucosa.
The B vitamins are readily absorbed from the gastrointestinal tract, except in malabsorption syndromes. Thiamine is absorbed mainly in the duodenum.
For more Absorption, Distribution and Excretion (Complete) data for Vitamin B1 (8 total), please visit the HSDB record page.

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Metabolism / Metabolites
Converted in vivo to thiamine diphosphate, a coenzyme in the decarboxylation of alpha-keto acids.
Compound 3-(2'-methyl-4'-amino-5'-pyrimidylmethyl)-4-methylthiazole-5-acetic acid, ie thiamine acetic acid, 2-methyl-4-amino-5-formylaminomethylpyrimidine, and 5-(2-hydroxyethyl)-4-methylthiazole have been identified as important metabolites of thiamine, vitamin B1.
Biotransformation of thiamine in mammals is generally supposed to /yield/ thiochrome, thiamine disulfide, 5-(2-hydroxyethyl)-4-methyl-thiazole, and some form corresponding to pyrimidine residue of thiamine.
Thiamine is metabolized in the liver of animals. Several urinary metabolites of thiamine have been identified in humans. Little or no unchanged thiamine is excreted in urine following administration of physiologic doses; however, following administration of larger doses, both unchanged thiamine and metabolites are excreted after tissue stores become saturated.

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Biological Half-Life
The biological half-life of the vitamin is in the range of 9-18 days.
With higher pharmacological levels, namely repetitive 250-mg amounts taken orally and 500 mg given intramuscularly, nearly 1 week was required for steady state plasma concentrations to be reached; a mean elimination half-life of 1.8 days was estimated.
Total thiamin content of the adult human has been estimated to be approximately 30 mg, and the biological half-life of the vitamin is probably in the range of 9 to 18 days.

Interactions
... High dietary levels of thiamine hydrochloride have been reported to depress the metabolism of zoxazolamine and aminopyrine in rats without significantly altering the oxidative metabolism of hexobarbitone. /Thiamine hydrochloride/
In rats treated with PCB, vitamin B1 levels in blood, liver, and sciatic nerve decreased, transketolase activity decreased, and pyrophosphate effect increased. In DDT-treated rats, vitamin B1 levels decreased in blood, brain, and liver, as did transketolase activity, while pyrophosphate effect increased.
Although the clinical importance is unknown, thiamine reportedly may enhance the effect of neuromuscular blocking agents.
... Alcohol inhibits absorption of thiamine.
For more Interactions (Complete) data for Vitamin B1 (9 total), please visit the HSDB record page.

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Non-Human Toxicity Values
LD50 Rat sc 560 mg/kg
LD50 Rat iv 188 mg/kg
LD50 Mouse sc 301 mg/kg
LD50 Mouse iv 83 mg/kg

[1]. Thiamine Deficiency and Delirium. Innov Clin Neurosci. 2013 Apr; 10(4): 26-32.

[2]. High-dose thiamine prevents brain lesions and prolongs survival ofSlc19a3-deficient mice. PLoS One. 2017; 12(6): e0180279.

Thiamine(1+) chloride is a vitamin B1 and an organic chloride salt. It contains a thiamine(1+).
3-((4-Amino-2-methyl-5-pyrimidinyl)methyl)-5-(2- hydroxyethyl)-4-methylthiazolium chloride.
See also: Thiamine (annotation moved to).

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Mechanism of Action
Metabolic control analysis predicts that stimulators of transketolase enzyme synthesis such as thiamin (vitamin B-1) support a high rate of nucleic acid ribose synthesis necessary for tumor cell survival, chemotherapy resistance, and proliferation. Metabolic control analysis also predicts that transketolase inhibitor drugs will have the opposite effect on tumor cells. This may have important implications in the nutrition and future treatment of patients with cancer.

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Therapeutic Uses
Thiamine is used to prevent and to treat thiamine deficiency syndromes including beriberi, Wernicke's encephalopathy syndrome, delirium, and peripheral neuritis associated with pellagra or neuritis of pregnancy (if associated with severe vomiting).
Although thiamine has not been shown by well-controlled trials to have any therapeutic value, the drug has been used for the management of poor appetite, ulcerative colitis, chronic diarrhea, other GI disorders, and the cerebellar syndrome. Thiamine has also been used orally as an insect repellent, but there is a lack of adequate evidence to establish the efficacy of thiamine for this use.
Low plasma thiamine concentrations have been found in patients with type 1 and type 2 diabetes mellitus. In a small placebo-controlled study, benfotiamine /a related vitamin B1 substance/ 100 mg given four times daily by mouth significantly improved neuropathic pain in patients with diabetic polyneuropathy. /Benfotiamine/
/This study assessed/ the effect of thiamine repletion on thiamine status, functional capacity, and left ventricular ejection fraction (LVEF) in patients with moderate to severe congestive heart failure (CHF) who had received furosemide in doses of 80 mg/d or more for at least 3 months. PATIENTS AND METHODS: Thirty patients were randomized to 1 week of double-blind inpatient therapy with either iv thiamine 200 mg/d or placebo (n = 15 each). All previous drugs were continued. Following discharge, all 30 patients received oral thiamine 200 mg/d as outpatients for 6 weeks. Thiamine status was determined by the erythrocyte thiamine-pyrophosphate effect (TPPE). LVEF was determined by echocardiography. RESULTS: TPPE, diuresis, and LVEF were unchanged with iv placebo. After iv thiamine, TPPE decreased (11.7% +/- 6.5% to 5.4% +/- 3.2%; P < 0.01). LVEF increased (0.28 +/- 0.11 to 0.32 +/- 0.09; P < 0.05), as did diuresis (1,731 +/- 800 mL/d to 2,389 +/- 752 mL/d; P < 0.02), and sodium excretion (84 +/- 52 mEq/d to 116 +/- 83 mEq/d, P < 0.05). In the 27 patients completing the full 7-week intervention, LVEF rose by 22% (0.27 +/- 0.10 to 0.33 +/- 0.11, P < 0.01). CONCLUSIONS: Thiamine repletion can improve left ventricular function and biochemical evidence of thiamine deficiency in some patients with moderate-to-severe CHF who are receiving longterm furosemide therapy.
For more Therapeutic Uses (Complete) data for Vitamin B1 (11 total), please visit the HSDB record page.

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Drug Warnings
Serious hypersensitivity/anaphylactic reactions can occur, especially after repeated administration. Deaths have resulted from IV or IM administration of thiamine.
Anaphylaxis as an adverse systemic reaction to thiamine (vitamin B1) has been described in the literature since 1938. Although its precise mechanism is still uncertain, the reaction appears to involve immediate type hypersensitivity and to be exclusively related to parenteral administration...
Anaphylaxis. There have been occasional reports of serious and even fatal responses to the parenteral administration of thiamin. The clinical characteristics have strongly suggested an anaphylactic reaction. Symptoms associated with thiamin-induced anaphylaxis include anxiety, pruritus, respiratory distress, nausea, abdominal pain, and shock, sometimes progressing to death.
Adverse reactions with thiamine are rare, but hypersensitivity reactions have occurred, mainly after parenteral doses. These reactions have ranged in severity from very mild to, very rarely, fatal anaphylactic shock ... The UK Committee on Safety of Medicines had received, between 1970 and July, 1988, 90 reports of adverse reactions associated with the use of an injection containing high doses of vitamins B and C. The most frequent reactions were anaphylaxis (41 cases, including 2 fatalities), dyspnea or bronchospasm (13 cases), and rash or flushing (22 cases); 78 of the reactions occurred during, or shortly after, intravenous injection and the other 12 after intramuscular injectdion. They recommended that parenteral treatment be used only when essential, and that, when given, facilities for treating anaphylaxis should be available. They also recommended that, when the intravenous route was used, the injection be given slowly (over 10 minutes). Various authors have noted that parenteral treatment is essential for the prophylaxis and treatment of Wernicke's encephalopathy. However, further reports of anaphylaxis to parenteral thiamine have since been described, including one with a fatal outcome.
For more Drug Warnings (Complete) data for Vitamin B1 (15 total), please visit the HSDB record page.

C12H17CLN4OS

300.8076

300.081

59-43-8

Thiamine nitrate;532-43-4;Thiamine hydrochloride;67-03-8

6042

White to off-white solid powder

6 g/cm3

125 °C

1.99

2

6

4

19

269

0

MYVIATVLJGTBFV-UHFFFAOYSA-M

InChI=1S/C12H17N4OS.ClH/c1-8-11(3-4-17)18-7-16(8)6-10-5-14-9(2)15-12(10)13;/h5,7,17H,3-4,6H2,1-2H3,(H2,13,14,15);1H/q+1;/p-1

2-[3-[(4-amino-2-methylpyrimidin-5-yl)methyl]-4-methyl-1,3-thiazol-3-ium-5-yl]ethanol;chloride

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

H2O : ≥ 100 mg/mL (~332.44 mM)
DMSO : ~1 mg/mL (~3.32 mM)

Solubility in Formulation 1: ≥ 100 mg/mL (332.44 mM) (saturation unknown) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution.

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 (Please use freshly prepared in vivo formulations for optimal results.)