Drug & supplement interaction

Tormentil + Erlotinib

Erlotinib brand name: Tarceva.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 27, 2026
The bottom line No known interaction

We found no known interaction between Tormentil and Erlotinib 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 Erlotinib states a food rule worth keeping to.

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Interaction report

Tormentil and Erlotinib

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 Erlotinib and Tormentil 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 Tormentil at all — not against Erlotinib, 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.

Tormentil safety at a glance

Tormentil overall Use caution Generally considered low-risk for short-term use, but human safety data are limited.
Pregnancy Avoid Not enough safety information, so it is best avoided during pregnancy.
Breastfeeding Avoid Safety has not been studied, so avoid use while breastfeeding.

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

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

What Tormentil Itself Has Been Linked To

This is not an interaction — nothing below involves Erlotinib. It is the side-effect record for Tormentil on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Tormentil, this list is the first place to look.

  • Heartburn / Stomach pain Additional detail

    “Orally, tormentil has been reported to cause mild abdominal pain, heartburn, and feelings of fullness in one clinical trial. These adverse effects occurred at the same frequency for doses ranging from 1.2 grams daily to 3 grams daily.”

    Tormentil · Natural Medicines adverse-effect record, reported in dyspepsia.

    1 source cited
    1. 78590. Huber, R., Ditfurth, A. V., Amann, F., Guthlin, C., Rostock, M., Trittler, R., Kummerer, K., and Merfort, I. Tormentil for active ulcerative colitis: an open-label, dose-escalating study. J.Clin.Gastroenterol. 2007;41(9):834-838. PubMed

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

How to take them

Some Erlotinib Products Have a Food Rule — Tormentil Should Not Break It

At least one FDA label for a product containing Erlotinib says to take it on an empty stomach. Most supplements — Tormentil included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Erlotinib on its own and move Tormentil to a meal later in the day.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Erlotinib 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.

Recommended Dose – NSCLC The recommended daily dose of erlotinib tablets for NSCLC is 150 mg taken on an empty stomach, i.e., at least one hour before or two hours after the ingestion of food.

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

Everything else you take

See Every Supplement That Interacts With Erlotinib

This page covers Tormentil only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Erlotinib page lists 18 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Bilberry (moderate), Coffee Charcoal (moderate), European Mandrake (moderate) and Glucomannan (moderate).

By severity: 1 major · 8 moderate · 9 minor.

From our pharmacist’s overview on the Erlotinib page

“Activated charcoal is the entry I would flag first for anyone taking erlotinib (Tarceva), an oral targeted therapy for certain lung cancers. Charcoal can adsorb the drug in the gut and cut how much reaches the bloodstream, and with a cancer pill, less absorbed means less cancer fought.”

Reviewed by 2 · Jul 18, 2026

Open the Erlotinib interaction page

How much people look this up

Where Tormentil and Erlotinib 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 Tormentil
Steady interest

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

29 days ago today
Medication Erlotinib
Steady interest

#2,520 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 Tormentil reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 27, 2026. The Tormentil and Erlotinib 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 Tormentil

What is Tormentil?

  • Diarrhea
  • Mouth and throat inflammation
  • Mild digestive upset
  • Sore throat (gargle)
  • Minor wounds and skin irritation

Tormentil is a traditional herb whose root is rich in tannins and has long been used for diarrhea and as a mouth rinse for sore gums or throat. Some small studies suggest it may help shorten diarrhea, but overall evidence is limited and quality is low. Talk to your pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding because safety is not established.

Potentilla erecta · Rosaceae · Root and rhizome (underground stem) · Tincture, liquid extract, tea, capsules, mouth rinse

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

Tormentil: dosing

There is no official, standardized dose for tormentil, and products vary widely in strength. Tinctures, extracts, teas, and capsules will each have different recommended amounts.The safest approach is to follow the directions on the product label and not exceed them. If you are using it as a mouth rinse, do not swallow large amounts.

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

Read the full Tormentil monograph & all interactions
Medication

About Erlotinib

What Is Erlotinib Used For?

Brand name: Tarceva

Erlotinib tablets are used to treat metastatic non-small cell lung cancer (NSCLC) in patients whose tumors carry specific gene changes — EGFR exon 19 deletions or exon 21 (L858R) mutations — confirmed by an FDA-approved test. It can be used as a first-line treatment, as maintenance therapy, or after at least one prior chemotherapy has stopped working.

Erlotinib tablets are also used for the first-line treatment of locally advanced, unresectable, or metastatic pancreatic cancer — but only in combination with another chemotherapy drug called gemcitabine. Erlotinib is not recommended alongside platinum-based chemotherapy regimens.

Most-Reported Side Effects for Erlotinib

From FAERS, the FDA’s public side-effect reporting system (12,441 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Diarrhea 1,339 reports
Rash 1,317 reports
Malignant neoplasm progression 890 reports
Fatigue 718 reports
Nausea 696 reports
See full Erlotinib drug information
Keep checking

Other Drugs & Tormentil

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

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

Tormentil References

The 1 references that drive our Tormentil 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. Huber, R., Ditfurth, A. V., Amann, F., Guthlin, C., Rostock, M., Trittler, R., Kummerer, K., and Merfort, I. Tormentil for active ulcerative colitis: an open-label, dose-escalating study. J.Clin.Gastroenterol. 2007;41(9):834-838. 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 Tormentil and Erlotinib Together: Common Questions

Is it safe to take Tormentil with Erlotinib?
We do not list a known interaction between Tormentil and Erlotinib. 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 Tormentil and Erlotinib at the same time of day?
At least one FDA label for a product containing Erlotinib says to take it on an empty stomach, and supplements are usually taken with a meal — so taking them together at breakfast is the easy mistake. Where that applies, keep Erlotinib on its own and move Tormentil to a meal later in the day. Food instructions belong to the product rather than the ingredient, so check the directions on your own box. This is about absorption, not an interaction.
Does Erlotinib interact with any supplements?
Yes. Erlotinib has documented interactions with 18 supplements in our database — Tormentil is not one of them. The Erlotinib 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

Tormentil monograph Uses, safety profile, and every drug interaction in one place Erlotinib drug information The full plain-English guide to this medication Erlotinib supplement interactions Every supplement checked against Erlotinib, 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 Erlotinib and Tormentil?

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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.