Thiamine (Vitamin B1)

Question 1

Class?

Answer 1

Vitamin

Question 2

Mechanism of Action?

Answer 2

• Required for carbohydrate metabolism.
• Deficiency leads to anemia, polyneuritis, Wernicke’s encephalopathy, cardiomyopathy.
• Admin may reverse symptoms of deficiency, but effects are dependent upon duration of illness and severity of disease.
• Chronic alcohol intake interferes with the absorption, intake, and utilization of thiamine.
• Patients who are malnourished, or have chronic alcohol abuse, may develop Wernicke’s encephalopathy if given IV glucose without concomitant administration of thiamine.

Question 3

Indications and Field Use?

Answer 3

• Alcoholism, delirium tremens.
• Coma of unknown origin, especially if alcohol or malnourished may be involved
• Suspect Wernicke or Korsakoff Syndrome
• Other thiamine deficiency syndromes
• Severe congestive heart failure
• Thiamine should precede the administration of Dextrose or Glucagon in any adult patient if there is any evidence of malnutrition or alcohol abuse.

Question 4

Contraindications?

Answer 4

• Do not give intra-arterial.

* Thiamine allergy.

Question 5

Adverse Reactions?

Answer 5

• Hypotension (rare)

* Nausea/Vomiting

Question 6

Incompatibility/Drug Interactions?

Answer 6

None

Question 7

Adult Dosage?

Answer 7

100 mg

Question 8

Pediatric Dosage?

Answer 8

Rarely used

Question 9

Routes of Administration?

Answer 9

IM

IV/IO over several minutes

Question 10

Onset of Action?

Answer 10

Hours

Question 11

Peak Effects?

Answer 11

3-5 days

Question 12

AZ Drug Box Minimum Supply?

Answer 12

100 mg

Question 13

Special Notes?

Answer 13

• In the known alcoholic patient, dextrose should not be administered without thiamine.
• Thiamine has been shown to be useful in severe congestive heart failure.