thiamine
Brand names: Vitamin B1
Thiamine hydrochloride injection is a form of vitamin B1. It is used to treat thiamine deficiency when you need rapid restoration of thiamine.
Drug Pricing (NADAC)
Generic Price
$2.65/unit
Generic Available
Yes (10 manufacturers)
Pricing data from NADAC (CMS), effective December 18, 2024. Compare all drug costs →
What it does
This medicine treats thiamine deficiency, also known as beriberi.
Common side effects
Feeling of warmth, Itching, Hives
Key warnings
In rare cases, you may have a severe allergic reaction to thiamine, especially after repeated injections.
How It Works
Thiamine helps your body turn food into energy. It is important for the health of your nerves, brain, muscles, heart, and digestive system. This injection increases the amount of thiamine in your body.
How to Take It
A healthcare provider will give you this injection into a muscle or vein. For beriberi, you may get 10 to 20 mg three times a day for up to two weeks. To maintain thiamine levels, you may then take a multivitamin containing 5 to 10 mg of thiamine daily for one month. Follow your doctor's instructions carefully.
Pregnancy & Breastfeeding
If you are pregnant, talk to your doctor before taking this medicine. It is sometimes used for neuritis of pregnancy if vomiting is severe.
Missed Dose
Since a healthcare provider gives this injection, you are not likely to miss a dose. If you have concerns, talk to your doctor.
Storage
Store at room temperature, away from light. Only use if the solution is clear and the seal is intact.
Side Effects (from patient reports)
Based on 6,772 FDA adverse event reports.
FDA Adverse Event Report Analysis
Detailed analysis of 11,724 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 2004–2025.
Total Reports
11,724
Death-Related Reports
1,816
Hospitalization Reports
6,403
Top Indication
Product Used For Unknown Indication
Gender Distribution
Age Distribution
Most Reported Adverse Reactions (FAERS)
| # | Reaction | Reports |
|---|---|---|
| 1 | OFF LABEL USE | 861 |
| 2 | NAUSEA | 765 |
| 3 | DRUG INEFFECTIVE | 748 |
| 4 | DYSPNOEA | 736 |
| 5 | DIARRHOEA | 679 |
| 6 | PAIN | 668 |
| 7 | FATIGUE | 620 |
| 8 | CONFUSIONAL STATE | 617 |
| 9 | VOMITING | 546 |
| 10 | MALAISE | 531 |
| 11 | DIZZINESS | 510 |
| 12 | HEADACHE | 505 |
| 13 | FALL | 498 |
| 14 | CONDITION AGGRAVATED | 497 |
| 15 | ACUTE KIDNEY INJURY | 484 |
Reactions in Death Reports
Reactions in Hospitalization Reports
Source: FDA FAERS (Adverse Event Reporting System) FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation
Serious Warnings
In rare cases, you may have a severe allergic reaction to thiamine, especially after repeated injections. This can cause collapse and death. "Wet" beriberi with heart failure is an emergency and must be treated with slow IV thiamine.
Common Questions
What is thiamine?
How will I receive this medication?
What should I do if I experience side effects?
Can I take this medication if I am allergic to thiamine?
How long will I need to take this medication?
Can I take this medication with other vitamins?
What if I have kidney problems?
Will this medication interact with my other medications?
Can I drive or operate machinery while taking this medication?
How will I know if the medication is working?
What are the common side effects of thiamine?
What drug class is thiamine?
Is thiamine safe during pregnancy?
Related Medications in Vitamin B1 Supplement
Other drugs grouped near thiamine — same-class peers and common alternatives.
ascorbic acid
Vitamin C
This medicine is a Vitamin C supplement.
Compare with thiamine →
biotin
Vitamin B7
Dialyvite with Zinc is a prescription vitamin supplement.
Compare with thiamine →
calcitriol
Rocaltrol
Calcitriol is a form of vitamin D that helps your body absorb and use calcium.
Compare with thiamine →
calcium carbonate
Tums, Caltrate
Calcium carbonate is a medicine that can relieve heartburn and upset stomach.
Compare with thiamine →
cholecalciferol
Vitamin D3
PNV-DHA is a multivitamin with minerals and essential fatty acids.
Compare with thiamine →
Medication Guides
Understanding Drug Interactions
How CYP450 enzymes, inhibitors, and inducers affect your medications
Generic vs Brand Name Drugs
FDA requirements, cost savings, and when the difference matters
Pain Relievers Compared
NSAIDs vs acetaminophen — which OTC pain reliever to use
Narrow Therapeutic Index Drugs
Why some drugs demand precise dosing and monitoring
Common Drug Interactions
Dangerous medication combinations and how to protect yourself
Related Health & Safety Data
🩺 Find a Doctor
Search prescribers for Vitamin B1 Supplement
🏨 Hospital Quality
CMS hospital ratings, safety scores & patient outcomes
💊 Supplement Data
NIH DSLD — check supplement ingredients & label claims
🍽️ Food Safety Alerts
FDA recalls, inspections & outbreak investigations
⚠️ Product Recalls
FDA, CPSC & NHTSA recall search
💉 Procedure Costs
Medicare procedure pricing for 9,297 procedures
What the FDA Data Shows for thiamine
The FDA label for thiamine (sold under brand names such as Vitamin B1) classifies it as an over-the-counter product in the Vitamin B1 Supplement class. This medicine treats thiamine deficiency, also known as beriberi. Official labeling lists 7 commonly reported side effects, including Feeling of warmth, Itching, Hives.
Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 6,772 voluntary reports. Interaction data is drawn directly from FDA-approved prescribing information. NADAC pricing from CMS shows a generic unit cost of $2.65.
Report counts do not establish causation — a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history, and patent information further shape supply and switching decisions. This page summarizes public FDA data for educational purposes only and is not a substitute for professional medical advice — always consult a licensed healthcare provider before starting, stopping, or changing any medication.
Data Sources
Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS). Pricing: CMS National Average Drug Acquisition Cost (NADAC).
FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. Always consult a healthcare professional before making medication decisions.
Last updated: July 8, 2025
Read our methodology — how this data is sourced, computed, and verified.
All federal data sources used on this page
- FDA Orange Book — approved drug products with therapeutic equivalence. accessdata.fda.gov/cder/ob
- FDA DailyMed — NIH-hosted drug labeling for FDA-approved meds. dailymed.nlm.nih.gov
- FDA Adverse Event Reporting System (FAERS) — post-marketing safety surveillance. fda.gov/drugs/faers
- NLM RxNorm — standardized clinical drug nomenclature. nlm.nih.gov/research/umls/rxnorm
- CMS Medicare Part B Drug Average Sales Price Files — federal drug pricing data. cms.gov/medicare/part-b-drugs/asp
- FDA Drug Shortages Database — current and resolved drug shortage tracking. accessdata.fda.gov/drugshortages