Drug & supplement interaction

Thiamine + Galantamine

Galantamine brand names: Reminyl, Razadyne.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Thiamine and Galantamine in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the label for Galantamine states a food rule worth keeping to.

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Interaction report

Thiamine and Galantamine

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Galantamine and Thiamine in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Thiamine safety at a glance

Thiamine overall Generally safe Thiamine is generally very safe when taken by mouth in normal amounts.
Pregnancy Likely Safe When used orally in dietary amounts of 1.4 mg daily. A tolerable upper intake level (UL) has not been established for healthy individuals. Read the full pregnancy detail
Breastfeeding Likely Safe When used orally in dietary amounts of 1.4 mg daily. A tolerable upper intake level (UL) has not been established for healthy individuals. Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Galantamine and Thiamine? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Galantamine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Galantamine is filed under 5 classifications — including acetylcholinesterase (ache) inhibitors, cholinergic drugs, cytochrome p450 2d6 (cyp2d6) substrates. Thiamine has documented interactions with 1 drug class — the most serious being trimethoprim (proloprim) (minor) — and none of Galantamine’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Thiamine Does Interact With Other Medications

Thiamine has 3 minor known drug interactions in our database — Galantamine isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Thiamine

Covers the 2,830 medications we’ve checked against Thiamine. Pick one to open its full report.

What to actually watch for

What Thiamine Itself Has Been Linked To

This is not an interaction — nothing below involves Galantamine. It is the side-effect record for Thiamine on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Thiamine, this list is the first place to look. One entry is worth acting on rather than waiting out — marked below.

  • Bleeding in the gut / Shortness of breath / A severe allergic reaction / Hives / Bleeding or bruising / An allergic reaction Worth acting on Additional detail

    “Orally, thiamine might rarely cause dermatitis and other allergic reactions. Parenterally, thiamine can cause anaphylactoid and hypersensitivity reactions, but this is also rare (”

    Thiamine · Natural Medicines adverse-effect record, reported in acute respiratory distress syndrome (ards).

    4 sources cited
    1. 15. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
    2. 35585. Rogovik, A. L., Vohra, S., and Goldman, R. D. Safety considerations and potential interactions of vitamins: should vitamins be considered drugs? Ann.Pharmacother. 2010;44(2):311-324. PubMed
    3. 105445. Thiamine hydrochloride injection package insert. Lake Zurich, IL: Fresenius Kabi, LLC; September 2019.
    4. 91170. Arruti N, Bernedo N, Audicana MT, Villarreal O, Uriel O, Muñoz D. Systemic allergic dermatitis caused by thiamine after iontophoresis. Contact Dermatitis. 2013 Dec;69(6):375-6. PubMed
  • Numbness or tingling / Low blood pressure / Itching / Swelling Additional detail

    Recorded for Thiamine in the same Natural Medicines adverse-effect record shown under Bleeding in the gut / Shortness of breath / A severe allergic reaction / Hives / Bleeding or bruising / An allergic reaction above.

Showing the 10 most notable of 11 recorded effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

Everything above comes from the Natural Medicines adverse-effect record for Thiamine — expand a row for the licensed statement it rests on. We read the ADVERSE REACTIONS section of Galantamine’s FDA label too, and the two lists don’t meaningfully overlap — which is why no Galantamine column appears here.

Special populations

Thiamine in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Safe

When used orally in dietary amounts of 1.4 mg daily. A tolerable upper intake level (UL) has not been established for healthy individuals.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

How to take them

Some Galantamine Products Have a Food Rule — Thiamine Should Not Break It

At least one FDA label for a product containing Galantamine says to take it with food. If you take Thiamine on an empty stomach out of habit, keep them separate — and take Galantamine with a meal where the label says to.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Galantamine products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

( 2.1 ) Take with food; ensure adequate fluid intake during treatment (2.1) Hepatic impairment: should not exceed 16 mg/day for moderate hepatic impairment; do not use in patients with severe hepatic impairment ( 2.2 ) Renal impairment: should not exceed 16 mg/day for creatinine clearance 9 to 59 mL/min; do not use in patients with creatinine clearance less than 9 mL/min.

From the Dosage and Administration section of the FDA label we read for Galantamine — where that label names a specific product, the instruction is that product's. See the Galantamine drug page ›

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

Overlapping uses

What Galantamine Is Prescribed For, and What Thiamine Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Galantamine is a prescription medicine with approved uses on its FDA label. Thiamine is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Galantamine is prescribed for: Galantamine — available as extended-release capsules, tablets, and an oral solution — is used to treat mild to moderate dementia caused by Alzheimer's disease. All supported formulations share this indication. It does not cure or slow the underlying disease, but it can help support cognitive function in people with early to moderate-stage Alzheimer's. Its benefits may lessen as the disease progresses and more brain cells are lost.

Thiamine has been studied for:

  • Dementia studied, not established Thiamine has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Thiamine for dementia

    It is unclear if oral thiamine is beneficial for the prevention of dementia.

  • Cognitive function studied, not established Thiamine has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Thiamine for cognitive function

    Oral thiamine has only been studied in combination with other ingredients; its effect when used alone is unclear.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Galantamine on your own; if you are taking Thiamine for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

Everything else you take

See Every Supplement That Interacts With Galantamine

This page covers Thiamine only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Galantamine page lists 170 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), 1,3-dmaa (moderate) and Acacia Rigidula (moderate).

By severity: 3 major · 126 moderate · 41 minor.

From our pharmacist’s overview on the Galantamine page

“Galantamine (Razadyne) treats Alzheimer's disease, so it is often a caregiver filling the pill organizer alongside memory supplements and morning juice. That pairing deserves genuine care, because three of the 170 supplement ingredients on file are rated major and two of them are everyday items.”

Reviewed by 2 · Jul 18, 2026

Open the Galantamine interaction page

One more smart check

Taking Thiamine as Part of a Dietary Supplement Product? Check It for Interactions

We hold 3 real supplement products containing Thiamine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Thiamine. Even though Thiamine itself has no known interaction with Galantamine, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Thiamine and Galantamine Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Thiamine
Top 25%

#179 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Galantamine
Top half

#1,111 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Thiamine reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Thiamine and Galantamine records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Thiamine

What is Thiamine?

  • Preventing or treating thiamine deficiency
  • Beriberi
  • Wernicke-Korsakoff syndrome (alcohol-related)
  • Supporting energy and nerve function
  • General B-vitamin supplementation

Thiamine (vitamin B1) is an essential nutrient your body needs to turn food into energy and to keep your nerves and heart healthy. Most people get enough from food, but supplements are clearly useful for deficiency, certain medical conditions, and people with heavy alcohol use. Talk with your pharmacist or doctor before starting it, especially if you have a chronic illness.

Tablets, capsules, oral liquids, injectable solutions (prescription), part of B-complex and multivitamins

An interaction check asks whether these two react with each other — it does not ask whether Thiamine is a good idea for someone in your situation. Here is what our Thiamine record says about it on its own.

Thiamine: dosing

The right dose of thiamine depends on your age, health, and the reason you are taking it. There is a recommended daily intake for general nutrition, and higher amounts are sometimes used by doctors to treat a deficiency.For supplements, the best approach is to follow the directions on the product label and not exceed them without guidance.

From our Thiamine monograph — the full record covers uses, side effects and every documented interaction.

Read the full Thiamine monograph & all interactions
Medication

About Galantamine

What Is Galantamine Used For?

Brand names: Reminyl, Razadyne

Galantamine — available as extended-release capsules, tablets, and an oral solution — is used to treat mild to moderate dementia caused by Alzheimer's disease. All supported formulations share this indication.

It does not cure or slow the underlying disease, but it can help support cognitive function in people with early to moderate-stage Alzheimer's. Its benefits may lessen as the disease progresses and more brain cells are lost.

Most-Reported Side Effects for Galantamine

From FAERS, the FDA’s public side-effect reporting system (3,188 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fall 812 reports
Cognitive disorder 664 reports
Constipation 651 reports
Balance disorder 632 reports
Hypotension 631 reports
See full Galantamine drug information
Keep checking

Other Drugs & Thiamine

Browse every other medication we’ve checked against Thiamine — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
0Moderate
3Minor
2,826No known interaction
Minor

3 interactions

No interaction 2,826 drugs checked — show the list
Evidence & sources

Thiamine References

The 7 references that drive our Thiamine monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  3. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
  4. Rogovik, A. L., Vohra, S., and Goldman, R. D. Safety considerations and potential interactions of vitamins: should vitamins be considered drugs? Ann.Pharmacother. 2010;44(2):311-324. PubMed
  5. Arruti N, Bernedo N, Audicana MT, Villarreal O, Uriel O, Muñoz D. Systemic allergic dermatitis caused by thiamine after iontophoresis. Contact Dermatitis. 2013 Dec;69(6):375-6. PubMed
  6. Thiamine hydrochloride injection package insert. Lake Zurich, IL: Fresenius Kabi, LLC; September 2019.
  7. Vora B, Wen A, Yee SW, et al. The Effect of Trimethoprim on Thiamine Absorption: A Transporter-Mediated Drug-Nutrient Interaction. Clin Pharmacol Ther 2023;114(2):381-392.

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Thiamine and Galantamine Together: Common Questions

Is it safe to take Thiamine with Galantamine?
We do not list a known interaction between Thiamine and Galantamine. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Should I take Thiamine and Galantamine at the same time of day?
At least one FDA label for a product containing Galantamine says to take it with food. If you take Thiamine on an empty stomach out of habit, keep them separate and take Galantamine with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Galantamine products can differ — so check the directions on your own box. This is about absorption, not an interaction.
Are Thiamine and Galantamine used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Thiamine in each. That is a conversation for your prescriber, especially if Galantamine is being adjusted to a target.
How was the Thiamine and Galantamine combination checked?
Interactions in our licensed database are recorded against drug classes. Galantamine is filed under 5 classifications, and Thiamine has documented interactions with 1 drug class — none of Galantamine's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Thiamine interact with any other medications?
Yes. Thiamine has 3 documented drug interactions in our database — Galantamine is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Galantamine interact with any supplements?
Yes. Galantamine has documented interactions with 170 supplements in our database — Thiamine is not one of them. The Galantamine interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Galantamine and Thiamine?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.