What is Vitamin B-1: Uses, Warnings & Interactions

Updated May 14, 2025  •  Published Dec 30, 2020

Vitamin B-1 overview

BRAND NAMES:

  • Optimum Vitamin B-1, Sundown Naturals B1, Sundown Naturals B1, Vitamin B1 AvPak, Sundown Naturals B1

Generic Names:

  • Vitamin B-1

Uses:

  • Thiamine, another name for Vitamin B-1, is used to treat thiamine-deficiency (not enough thiamine in the body).

Therapeutic Classes:

  • Nutriceutical, Nutritive Agent

Forms:

  • Tablet, Capsule, Liquid

How it’s taken:

  • By mouth

What is Vitamin B-1 used for?

What form(s) does Vitamin B-1 come in

  • Tablet

  • Capsule

  • Liquid

What are common Vitamin B-1 doses?

  • Bottle 100 Tablets

Common Vitamin B-1 prescriptions

  • Vitamin B-1
    100 tablets bottle

How to take Vitamin B-1

  • Your doctor will tell you how much and when to take your medicine. Keep all medicine away from children.

  • You may take your medicine with or without food.

  • Measure your oral liquid medicine using a marked measuring spoon or medicine cup.

  • Your doctor will tell you how much and when to take your medicine. Keep all medicine away from children.

  • You may take your medicine with or without food.

  • Measure your oral liquid medicine using a marked measuring spoon or medicine cup.

  • Missing a dose is generally not a cause for concern.

What to do if you miss a dose of Vitamin B-1

  • Take the missed dose as soon as possible.

  • Skip the missed dose if it is almost time for your next dose.

  • Missing a dose is generally not a cause for concern.

  • You should not use two doses at the same time.

Vitamin B-1 contraindications

  • You should not use this medicine if you have had an allergic reaction to thiamine (Vitamin B-1).

Vitamin B-1 warnings

  • Tell your doctor if you are pregnant or breastfeeding, or if you become pregnant.

  • Swelling of face, lips or eyelids

Vitamin B-1 interactions

  • Follow your doctor's orders if he or she has given you a special diet.

Vitamin B-1 side effects

Serious Side Effects

  • Swelling of face, lips or eyelids

  • Itching or trouble breathing