Drug & supplement interaction

Benfotiamine + Duloxetine

Duloxetine brand names: Cymbalta, Drizalma Sprinkle, Irenka.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Benfotiamine and Duloxetine 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 two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Benfotiamine and Duloxetine

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 Duloxetine and Benfotiamine 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.

Worth understanding: our licensed dataset holds no drug-interaction record for Benfotiamine at all — not against Duloxetine, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.

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.

Benfotiamine safety at a glance

Benfotiamine overall Use caution Generally well tolerated in studies, but long-term safety is not fully known.
Pregnancy Use caution Not enough safety information exists, so avoid unless your doctor advises otherwise.
Breastfeeding Use caution Safety while breastfeeding has not been well studied, so caution is advised.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Duloxetine and Benfotiamine? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Benfotiamine and Duloxetine May Share a Side Effect

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do.

  • Stomach upset Additional detail

    Benfotiamine

    “Orally, slight gastrointestinal discomfort has been reported in six out of 98 patients taking benfotiamine 300-600 mg daily for 6 weeks in one clinical study. The rate of adverse events was not different between treatment and placebo groups.”

    Benfotiamine · Natural Medicines adverse-effect record, reported in myasthenia gravis.

    1 source cited
    1. 98032. Stracke H, Gaus W, Achenbach U, Federlin K, Bretzel RG. Benfotiamine in diabetic polyneuropathy (BENDIP): results of a randomised, double blind, placebo-controlled clinical study. Exp Clin Endocrinol Diabetes 2008;116(10):600-5. PubMed

    Duloxetine

    Listed in the ADVERSE REACTIONS section of the FDA label for Duloxetine. Read the label on DailyMed ›

Effects for Duloxetine come from the ADVERSE REACTIONS section of its FDA label; effects for Benfotiamine come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Overlapping uses

What Duloxetine Is Prescribed For, and What Benfotiamine Has Been Studied For

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

Duloxetine is prescribed for: Duloxetine delayed-release capsules treat major depressive disorder (MDD) and generalized anxiety disorder (GAD) in adults. They also manage diabetic peripheral neuropathic pain (nerve pain from diabetes), fibromyalgia, and chronic musculoskeletal pain (such as chronic low back pain and pain from osteoarthritis) in adults. GAD is also approved in pediatric patients 7 years and older for Cymbalta, Drizalma Sprinkle, and certain duloxetine delayed-release capsule products. Fibromyalgia is approved in patients 13 years and older for Cymbalta and some duloxetine delayed-release capsule products.

Read the rest of what Duloxetine is prescribed for

Age-specific approvals vary by product — follow your prescriber's guidance on which product is right for your age group.

Benfotiamine has been studied for:

  • Diabetic neuropathy Natural Medicines rates the evidence for Benfotiamine: Possibly Effective Read what the research shows

    Benfotiamine for diabetic neuropathy

    Oral benfotiamine might improve symptoms of diabetic neuropathy.

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

    Benfotiamine for osteoarthritis

    Oral benfotiamine has only been evaluated in combination with other B vitamins; 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 Duloxetine on your own; if you are taking Benfotiamine for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Benfotiamine or Duloxetine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Benfotiamine or Duloxetine, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Duloxetine

This page covers Benfotiamine only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Duloxetine page lists 132 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Lithium (major), Siberian Cocklebur (major) and Wine (major).

By severity: 5 major · 107 moderate · 20 minor.

Open the Duloxetine interaction page

One more smart check

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

We hold 358 real supplement products containing Benfotiamine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Benfotiamine. Even though Benfotiamine itself has no known interaction with Duloxetine, 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 Benfotiamine and Duloxetine 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 Benfotiamine
Top 25%

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

29 days ago today
Medication Duloxetine
Top 5%

#47 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 Benfotiamine reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Benfotiamine and Duloxetine 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 Benfotiamine

What is Benfotiamine?

Benfotiamine
  • Diabetic nerve pain (neuropathy)
  • Supporting healthy nerve function
  • Thiamine deficiency
  • Oxidative stress
  • General wellness

Benfotiamine is a man-made, fat-soluble form of vitamin B1 (thiamine) that the body may absorb more easily than regular thiamine. It is mostly studied for diabetic nerve problems, but the evidence is mixed and limited, so it should not replace prescribed treatments. Talk with your pharmacist or doctor before starting it.

Synthetic compound (a derivative of vitamin B1) · Tablets, capsules

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

Benfotiamine: dosing

There is no official standardized dose of benfotiamine for any condition. Do not assume that taking more will work better, and avoid using it to self-treat a serious condition without medical guidance.

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

Read the full Benfotiamine monograph & all interactions
Medication

About Duloxetine

What Is Duloxetine Used For?

Brand names: Cymbalta, Drizalma Sprinkle, Irenka

Duloxetine delayed-release capsules treat major depressive disorder (MDD) and generalized anxiety disorder (GAD) in adults. They also manage diabetic peripheral neuropathic pain (nerve pain from diabetes), fibromyalgia, and chronic musculoskeletal pain (such as chronic low back pain and pain from osteoarthritis) in adults.

GAD is also approved in pediatric patients 7 years and older for Cymbalta, Drizalma Sprinkle, and certain duloxetine delayed-release capsule products. Fibromyalgia is approved in patients 13 years and older for Cymbalta and some duloxetine delayed-release capsule products. Age-specific approvals vary by product — follow your prescriber's guidance on which product is right for your age group.

See full Duloxetine drug information
Keep checking

Other Drugs & Benfotiamine

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

0Major
0Moderate
0Minor
2,829No known interaction
2,829 No interaction
No interaction 2,829 drugs checked — show the list

We also checked Benfotiamine against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Benfotiamine list.

See the full Benfotiamine interactions page
See every supplement checked against Duloxetine, ranked by severity
Evidence & sources

Benfotiamine References

The 1 references that drive our Benfotiamine 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. Stracke H, Gaus W, Achenbach U, Federlin K, Bretzel RG. Benfotiamine in diabetic polyneuropathy (BENDIP): results of a randomised, double blind, placebo-controlled clinical study. Exp Clin Endocrinol Diabetes 2008;116(10):600-5. PubMed

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 Benfotiamine and Duloxetine Together: Common Questions

Is it safe to take Benfotiamine with Duloxetine?
We do not list a known interaction between Benfotiamine and Duloxetine. 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.
Do Benfotiamine and Duloxetine have any of the same side effects?
Yes — our sources link each of them separately to one of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Are Benfotiamine and Duloxetine 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 Benfotiamine in each. That is a conversation for your prescriber, especially if Duloxetine is being adjusted to a target.
Does Duloxetine interact with any supplements?
Yes. Duloxetine has documented interactions with 132 supplements in our database — Benfotiamine is not one of them. The Duloxetine interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Benfotiamine monograph Uses, safety profile, and every drug interaction in one place Duloxetine drug information The full plain-English guide to this medication Duloxetine supplement interactions Every supplement checked against Duloxetine, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 1 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Duloxetine and Benfotiamine?

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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.