Thiamine
Synonym :
Vitamin B1
Mechanism :
Vitamin B1 is a water-soluble B complex vitamin. Vitamin B1 combines with adenosine triphosphate (ATP) to form thiamine pyrophosphate, also known as co carboxylase, a coenzyme. Its role in carbohydrate metabolism is the decarboxylation of pyruvic acid and alpha-ketoacids to acetaldehyde and carbon dioxide. Increased levels of pyruvic acid in the blood indicate vitamin B1 deficiency.
Indication :
- Maple syrup urine disease (MSUD)-thiamine sensitive variants
- Congenital lactic acidosis
- Mitochondrial respiratory chain defects
- Beri
Contraindications :
Hypersensitivity to vitamin B1 or any component of a product containing vitamin B1.
Dosing :
RDA:
0-6 months: 0.2 mg daily.
6-12 months: 0.3 mg daily.
1-3 years: 0.5 mg daily.
3-8 years: 0.6 mg daily.
8-13 years: 0.9 mg daily.
13-18 years: 1.2 mg daily (Male); 1 mg daily (females).
Congenital lactic acidosis, MSUD:
Oral 100 mg once daily.
Usual Pediatric Dose for Beriberi:
10 to 25 mg IM or IV daily (if critically ill), or 10 to 50 mg orally every day for 2 weeks, then 5 to 10 mg orally daily for 1 month.
Adverse Effect :
Feeling of warmth, pruritus, urticaria, weakness, sweating, nausea, restlessness, tightness of the throat, angioneurotic edema, cyanosis, pulmonary edema, hemorrhage into the gastrointestinal tract, collapse and death have been rarely reported, mainly following repeated IV administration of the drug.
Interaction :
Potentially Fatal: May enhance the effect of neuromuscular blocking agents.
Hepatic Dose :
No dosage adjustments are recommended.