Drug & supplement interaction

Yellow Toadflax + Trandolapril, Verapamil

Trandolapril, Verapamil brand name: Tarka.

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

We found no known interaction between Yellow Toadflax and Trandolapril, Verapamil 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 Trandolapril, Verapamil states a food rule worth keeping to.

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Interaction report

Yellow Toadflax and Trandolapril, Verapamil

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 Trandolapril, Verapamil and Yellow Toadflax 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 Yellow Toadflax at all — not against Trandolapril, Verapamil, 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.

Yellow Toadflax safety at a glance

Yellow Toadflax overall Use caution Modern safety data are very limited, so use cautiously and only short-term.
Pregnancy Avoid Not enough safety information; avoid use during pregnancy.
Breastfeeding Avoid No reliable safety data, so avoid while breastfeeding.

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

Still wondering about combining Trandolapril, Verapamil and Yellow Toadflax? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Trandolapril, Verapamil’s Own FDA Label Lists

This is not an interaction — none of it involves Yellow Toadflax. These are the most notable effects listed in the ADVERSE REACTIONS section of Trandolapril, Verapamil’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you take both. 10 of them are worth acting on rather than waiting out — marked below.

  • A stroke or mini-stroke Worth acting on
  • A bowel blockage Worth acting on
  • High potassium Worth acting on
  • Low sodium Worth acting on
  • Unsteadiness Worth acting on
  • A slow heartbeat Worth acting on
  • A heart attack Worth acting on
  • Pancreatitis Worth acting on
  • Fainting Worth acting on
  • Confusion Worth acting on

Showing the 10 most notable of 50 label-listed effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

From the ADVERSE REACTIONS section of the FDA label for Trandolapril, Verapamil. Read the label on DailyMed › Yellow Toadflax’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Yellow Toadflax side to compare — that is a limit of the record, not a statement that Yellow Toadflax has no side effects.

How to take them

Some Trandolapril, Verapamil Products Have a Food Rule — Yellow Toadflax Should Not Break It

At least one FDA label for a product containing Trandolapril, Verapamil says to take it with food. If you take Yellow Toadflax on an empty stomach out of habit, keep them separate — and take Trandolapril, Verapamil 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 Trandolapril, Verapamil 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.

Trandolapril and verapamil hydrochloride extended-release tablets should be administered with food.

From the Dosage and Administration section of the FDA label we read for Trandolapril, Verapamil — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

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.

Everything else you take

See Every Supplement That Interacts With Trandolapril, Verapamil

This page covers Yellow Toadflax only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Trandolapril, Verapamil page lists 304 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Asarabacca (major) and Beer (major).

By severity: 11 major · 250 moderate · 43 minor.

From our pharmacist’s overview on the Trandolapril, Verapamil page

“This is one of the supplement lists I would want a patient to read closely, not skim. Tarka combines trandolapril and verapamil to lower blood pressure, and most of these interactions pull on that same lever, either dropping pressure further than intended or working against the medicine altogether.”

Reviewed by 2 · Jul 18, 2026

Open the Trandolapril, Verapamil interaction page

How much people look this up

Where Yellow Toadflax and Trandolapril, Verapamil 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 Yellow Toadflax
Steady interest

#1,421 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Trandolapril, Verapamil
Top 25%

#514 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. Yellow Toadflax is not yet covered by that licensed database, so its write-up cites publicly available medical sources directly (see the references below).
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Yellow Toadflax reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Yellow Toadflax and Trandolapril, Verapamil records this page draws on were last updated June 22, 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 Yellow Toadflax

What is Yellow Toadflax?

  • Hemorrhoids and skin irritation
  • Mild constipation
  • Fluid retention (as a folk diuretic)
  • Liver and gallbladder complaints (traditional)
  • Minor wounds and inflammation (topical)

Yellow toadflax is a traditional folk remedy used mostly for hemorrhoids, skin problems, and as a mild laxative or diuretic, but there is very little modern human research to confirm any of these uses. Because its safety has not been well studied, it is best used cautiously, avoided in pregnancy and breastfeeding, and discussed with a pharmacist or doctor first.

Linaria vulgaris · Plantaginaceae · Aerial parts (flowering tops, leaves, and stems) · Tea, tincture, dried herb, ointment or salve, poultice

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

Yellow Toadflax: dosing

There is no well-established or standardized dose for yellow toadflax. Traditional preparations vary widely, and modern guidelines for safe amounts do not exist.If you choose to use a commercial product, follow the directions on the label and do not exceed them.

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

Read the full Yellow Toadflax monograph & all interactions
Keep checking

Other Drugs & Yellow Toadflax

Browse every other medication we’ve checked against Yellow Toadflax — 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 Yellow Toadflax 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 Yellow Toadflax list.

See the full Yellow Toadflax interactions page
See every supplement checked against Trandolapril, Verapamil, ranked by severity
Evidence & sources

Yellow Toadflax References

The 1 sources that drive our Yellow Toadflax monograph — publicly available pages from reputable medical and government organizations. Every link was verified to work before publishing. Yellow Toadflax is not covered by the licensed Natural Medicines interaction database, so its page cites these public sources directly.

  1. Dietary and Herbal Supplements — NIH NCCIH Source

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 Yellow Toadflax and Trandolapril, Verapamil Together: Common Questions

Is it safe to take Yellow Toadflax with Trandolapril, Verapamil?
We do not list a known interaction between Yellow Toadflax and Trandolapril, Verapamil. 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 Yellow Toadflax and Trandolapril, Verapamil at the same time of day?
At least one FDA label for a product containing Trandolapril, Verapamil says to take it with food. If you take Yellow Toadflax on an empty stomach out of habit, keep them separate and take Trandolapril, Verapamil with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Trandolapril, Verapamil products can differ — so check the directions on your own box. This is about absorption, not an interaction.
Does Trandolapril, Verapamil interact with any supplements?
Yes. Trandolapril, Verapamil has documented interactions with 304 supplements in our database — Yellow Toadflax is not one of them. The Trandolapril, Verapamil 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

Yellow Toadflax monograph Uses, safety profile, and every drug interaction in one place Trandolapril, Verapamil supplement interactions Every supplement checked against Trandolapril, Verapamil, 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 Trandolapril, Verapamil and Yellow Toadflax?

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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.