Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Capsule, Oral, as hydrochloride:
Generic: 50 mg
Solution, Injection, as hydrochloride:
Generic: 100 mg/mL (2 mL)
Tablet, Oral, as hydrochloride:
Generic: 50 mg, 100 mg, 250 mg
Tablet, Oral, as hydrochloride [preservative free]:
Generic: 100 mg [DSC]
Tablet, Oral, as mononitrate:
Generic: 100 mg
Tablet, Oral, as mononitrate [preservative free]:
Generic: 100 mg
Mechanism of Action
An essential coenzyme in carbohydrate metabolism by combining with adenosine triphosphate to form thiamine pyrophosphate.
When used for the treatment of ethylene glycol poisoning, thiamine is theorized to increase the formation of glycine, a nontoxic metabolite.
Oral: Adequate; IM: Rapid and complete
Highest concentrations found in brain, heart, kidney, liver
In the liver
Urine (as unchanged drug and as pyrimidine after body storage sites become saturated)
Use: Labeled Indications
Treatment of thiamine deficiency (including thiamine deficiency in pregnancy associated with neuropathy), beriberi (dry or wet variety), Wernicke encephalopathy, infantile beriberi with acute collapse, cardiovascular disease due to thiamine deficiency, or when giving IV dextrose to individuals with marginal thiamine status to avoid precipitation of heart failure; dietary supplement.
Use: Off Label
Alcohol withdrawal syndrome (adjunct)c
Data from a limited number of patients studied suggest that thiamine may be beneficial as an adjunct in the management of alcohol withdrawal syndrome to prevent Wernicke encephalopathy Cook 1998, Latt 2014, Sechi 2007, Thomson 2002. Additional data may be necessary to further define the role of thiamine in this condition.
Ethylene glycol poisoningc
The American Academy of Clinical Toxicology (AACT) guidelines recognize the lack of human clinical data for this use and consider it as a use in ethylene glycol poisoning without a formal or evidence-based recommendation, especially in patients who may have vitamin deficiencies (eg, patients with alcoholism) Barceloux 1999.
Sepsis (severe) or septic shockc
Data from one small retrospective before/after study suggest that IV thiamine in combination with IV ascorbic acid (vitamin C) and IV hydrocortisone in patients with severe sepsis or septic shock may be effective in decreasing mortality and preventing organ dysfunction Marik 2017.
Hypersensitivity to thiamine or any component of the formulation
Dosage and Administration
Marginal thiamine status (to avoid precipitating heart failure): IV: 100 mg thiamine in each of the first few liters of IV fluid in patients with marginal thiamine status to whom dextrose is being administered.
Parenteral nutrition supplementation (Vanek 2012): IV: 6 mg/day
Thiamine deficiency (beriberi): 5 to 30 mg/dose IM or IV 3 times daily (if critically ill); then 5 to 30 mg orally daily in single or divided doses 3 times daily for 1 month.
Manufacturer's labeling: Dosing in the prescribing information may not reflect current clinical practice. 10 to 20 mg IM 3 times daily for as long as 2 weeks followed by an oral multivitamin preparation containing 5 to 10 mg thiamine administered daily for 1 month.
Alcohol withdrawal syndrome (adjunct) (off-label use): 100 to 250 mg IV or IM once daily for 3 to 5 days (Cook 1998; Latt 2014; Sechi 2007; Thomson 2002) followed by 100 mg orally 3 times daily for 1 to 2 weeks then 100 mg orally daily thereafter (Latt 2014). Additional data may be necessary to further define the role of thiamine in this condition.
Ethylene glycol poisoning (off-label use): IV: 100 mg per day until the intoxication has resolved (Hoffman 2015)
Sepsis (severe) or septic shock (off-label use): IV: 200 mg every 12 hours over 30 minutes for 4 days or until ICU discharge; administer in combination with IV ascorbic acid (vitamin C) and IV hydrocortisone (Marik 2017).
Prophylaxis (off-label use): 100 to 250 mg IV or IM once daily for 3 to 5 days (Cook 1998; Latt 2014; Sechi 2007; Thomson 2002) followed by 100 mg orally three times daily for 1 to 2 weeks then 100 mg orally daily thereafter (Latt 2014).
Treatment: Initial: 200 to 500 mg IV 3 times daily for 2 to 7 days (Cook 1998; Latt 2014; Sechi 2007; Thomson 2002). If response to thiamine, continue with 250 mg IV or IM once daily for an additional 3 to 5 days (or until clinical improvement ceases) followed by 30 mg orally twice daily thereafter (Sechi 2007) or 100 mg orally 3 times daily for 1 to 2 weeks followed by 100 mg orally once daily thereafter (Latt 2014).
Manufacturer's labeling: Dosing in the prescribing information may not reflect current clinical practice. Initial: 100 mg IV, then 50 to 100 mg IM daily.
Refer to adult dosing.
Note: Dosing presented in mcg/kg, mg/kg, and mg/day; use precaution.
Parenteral nutrition, maintenance requirement (Vanek 2012): Limited data available: IV:
Infants: 0.35 to 0.5 mg/kg/day; maximum daily dose: 1.2 mg/day
Children: 1.2 mg/day
Thiamine deficiency (beriberi); treatment (critically ill):
Infants: Various regimens reported: Initial: IV: 25 to 50 mg once, followed by 10 mg IM once daily for a week then 3 to 5 mg orally once daily for at least 6 weeks (WHO 1999). Other regimens with higher initial doses have also been reported. One study used an oral dose of 100 mg/day given as 25 mg, 25 mg, and 50 mg doses administered 30 minutes apart for 3 days (Coats 2012). Another study administered 30 mg orally once daily for 20 days (Barennes 2015). Note: If patient is being breast-fed, the mother should also be considered for thiamine deficiency treatment (Bowman 2013).
Children: Limited data available: IM, IV: 10 mg once daily for the first week (if critically ill), then 3 to 5 mg orally once daily for at least 6 weeks (Kliegman 2016)
Adolescents: Limited data available: IM, IV: 100 mg once daily for up to 7 days (if critically ill), then 10 mg orally once daily. Dosing based on several case reports (n=3, age 14 to 17 years) of beriberi treatment after gastric bypass surgery (Towbin 2004)
A 100 mg/mL oral suspension may be made with commercially available thiamine powder. Add 10 g of powder to a mortar. Add small portions of a 1:1 mixture of Ora-Sweet® and Ora-Plus® and mix to a uniform paste; mix while adding the vehicle in equal proportions to almost 100 mL; transfer to a calibrated bottle, rinse mortar with vehicle, and add sufficient quantity of vehicle to make 100 mL. Label "shake well". Stable 91 days under refrigeration or at room temperature.
Ensom MH and Decarie D, "Stability of Thiamine in Extemporaneously Compounded Suspensions," Can J Hosp Pharm, 2005, 58(1):26-30.
IM, IV: Parenteral form may be administered by IM or IV injection. Various rates of administration have been reported (eg, 100 mg over 5 minutes). An extended infusion time is preferred for doses ≥100 mg. Local injection reactions may be minimized by slow administration (~30 minutes) into larger, more proximal veins. Thiamine should be administered prior to parenteral glucose solutions to prevent precipitation of acute symptoms of thiamine deficiency in the poorly nourished.
Dietary sources include legumes, pork, beef, whole grains, yeast, and fresh vegetables. A deficiency state can occur in as little as 3 weeks following total dietary absence.
Dietary reference intake (IOM 1998):
0 to 6 months: Adequate intake: 0.2 mg/day
7 to 12 months: Adequate intake: 0.3 mg/day
1 to 3 years: RDA: 0.5 mg
4 to 8 years: RDA: 0.6 mg
9 to 13 years: RDA: 0.9 mg
14 to 18 years: RDA: Females: 1 mg; Males: 1.2 mg
≥19 years: RDA: Females: 1.1 mg; Males: 1.2 mg
Pregnancy, lactation: RDA: 1.4 mg
Injection: Store at 15°C to 30°C (59°F to 86°F). Protect from light.
Etamsylate: May diminish the therapeutic effect of Thiamine. Management: If a patient is to receive intravenous (IV) etamsylate and an IV infusion containing thiamine, administer etamsylate first to avoid thiamine degradation by sulfites contained in the etamsylate product. Consider therapy modification
False-positive for uric acid using the phosphotungstate method and for urobilinogen using the Ehrlich's reagent; large doses may interfere with the spectrophotometric determination of serum theophylline concentration
Adverse reactions reported with injection. Frequency not defined.
Central nervous system: Flushing sensation, restlessness
Dermatologic: Diaphoresis, pruritus, skin sclerosis (at the injection site following IM administration), urticaria
Hematologic & oncologic: Hemorrhage (into the gastrointestinal tract)
Hypersensitivity: Anaphylaxis (following IV administration), angioedema, hypersensitivity reaction (following IV administration)
Local: Tenderness at injection site (following IM administration)
Neuromuscular & skeletal: Weakness
Respiratory: Cyanosis, pharyngeal edema, pulmonary edema
Concerns related to adverse effects:
- Hypersensitivity reactions: Have been reported following repeated parenteral doses; consider skin test in individuals with history of allergic reactions.
Concurrent drug therapy issues:
- Dextrose: Administration of dextrose may precipitate acute symptoms of thiamine deficiency; use caution when thiamine status is marginal or suspect.
Dosage form specific issues:
- Aluminum: The parenteral product may contain aluminum; toxic aluminum concentrations may be seen with high doses, prolonged use, or renal dysfunction. Premature neonates are at higher risk due to immature renal function and aluminum intake from other parenteral sources. Parenteral aluminum exposure of >4 to 5 mcg/kg/day is associated with CNS and bone toxicity; tissue loading may occur at lower doses (Federal Register 2002).
- Parenteral administration: Use with caution with parenteral route (especially IV) of administration.
- Vitamin deficiency: Single vitamin deficiency is rare; evaluate for other deficiencies.
Pregnancy Risk Factor
Water soluble vitamins cross the placenta. Thiamine requirements are increased in during pregnancy (IOM 1998).
Pregnant females are at increased risk of thiamine deficiency when prolonged nausea and vomiting (including hyperemesis gravidarum) occurs; deficiency may present as a polyneuropathy or Wernicke encephalopathy (Chiossi 2006; Karjalainen 1965; WHO 1999).
Thiamine supplementation is recommended in pregnant females with prolonged vomiting. Initial treatment with IV thiamine is needed when Wernicke encephalopathy is suspected. Oral, IM, or IV therapy may be considered depending on severity of thiamine deficiency (Berdai 2016; Chiossi 2006; Palacios-Marqués 2012). When intravenous hydration is used in the management of hyperemesis gravidarum, thiamine should be administered prior to infusing dextrose to prevent Wernicke encephalopathy (ACOG 189 2018).
What is this drug used for?
- It is used to prevent or treat thiamine (vitamin B1) deficiency.
Frequently reported side effects of this drug
- Sensation of warmth
- Sweating a lot
- Injection site irritation
Other side effects of this drug: Talk with your doctor right away if you have any of these signs of:
- Blue/gray skin discoloration
- Black, tarry, or bloody stools
- Vomiting blood
- Severe abdominal pain
- Shortness of breath
- Signs of a significant reaction like wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat.
Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.
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