Drug & supplement interaction

Marsh Blazing Star + Tretinoin

Tretinoin brand names: Vesanoid, Retin-A, Renova, Altreno.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Marsh Blazing Star and Tretinoin 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 Tretinoin states a food rule worth keeping to, and 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

Marsh Blazing Star and Tretinoin

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 Tretinoin and Marsh Blazing Star 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 Marsh Blazing Star at all — not against Tretinoin, 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.

Marsh Blazing Star safety at a glance

Marsh Blazing Star overall Not established There is not enough reliable human research to judge its safety.
Pregnancy Avoid Avoid because of traditional use affecting menstruation and a lack of safety data.
Breastfeeding Avoid Avoid due to lack of safety information while breastfeeding.

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

Still wondering about combining Tretinoin and Marsh Blazing Star? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Marsh Blazing Star and Tretinoin May Share Several of the Same Side Effects

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. One of them is worth acting on rather than waiting out — marked below.

  • Liver problems Worth acting on Additional detail

    Marsh Blazing Star

    “Orally, marsh blazing star, which contains coumarin, can be associated with nausea and vomiting, diarrhea, dizziness, insomnia, asymptomatic SGOT elevations, and liver toxicity (6,18).

    Topically, handling the plant can cause contact dermatitis.

    Marsh blazing star can cause an allergic reaction in individuals sensitive to the Asteraceae/Compositae family.”

    Marsh Blazing Star · Natural Medicines adverse-effect record, reported in dermatitis.

    5 sources cited
    1. 286. Mohler JL, Gomella LG, Crawford ED, et al. Phase II evaluation of coumarin (1,2-benzopyrone) in metastatic prostatic carcinoma. Prostate 1992;20:123-31. PubMed
    2. 287. Marshall ME, Butler K, Fried A. Phase I evaluation of coumarin (1,2 benzopyrone) and cimetidine in patients with advanced malignancies. Mol Biother 1991;3:170-8.
    3. 6. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
    4. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
    5. 3837. Goerz G, Wirth G, Maas B, et al. [Allergic contact dermatitis due to Asteraceae (Compositae). Cross reaction with Liatris spicata]. Derm Beruf Umwelt 1985;33:95-8.

    Tretinoin

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

  • Trouble sleeping / A skin rash / Vomiting / Dizziness / Diarrhea / Nausea reported in 5.6% of FDA reports for Tretinoin Additional detail

    Marsh Blazing Star

    Recorded for Marsh Blazing Star in the same Natural Medicines adverse-effect record shown under Liver problems above.

    Tretinoin

    Listed in the ADVERSE REACTIONS section of the FDA label for Tretinoin, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

Reported for Marsh Blazing Star but not commonly for Tretinoin: an allergic reaction.

Effects for Tretinoin come from the ADVERSE REACTIONS section of its FDA label; effects for Marsh Blazing Star come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 8,580 voluntary FDA FAERS reports for Tretinoin that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

How to take them

Some Tretinoin Products Have a Food Rule — Marsh Blazing Star Should Not Break It

At least one FDA label for a product containing Tretinoin says to take it with food. If you take Marsh Blazing Star on an empty stomach out of habit, keep them separate — and take Tretinoin 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 Tretinoin 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.

Take tretinoin capsules with a meal.

From the Dosage and Administration section of the FDA label we read for Tretinoin — 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 Tretinoin

This page covers Marsh Blazing Star only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Tretinoin page lists 52 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Vitamin A (major), African Wild Potato (moderate), Alfalfa (moderate) and Angelica Archangelica (moderate).

By severity: 2 major · 37 moderate · 13 minor.

Open the Tretinoin interaction page

How much people look this up

Where Marsh Blazing Star and Tretinoin 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 Marsh Blazing Star
Steady interest

#1,048 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Tretinoin
Steady interest

#2,080 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 Marsh Blazing Star reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Marsh Blazing Star and Tretinoin 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 Marsh Blazing Star

What is Marsh Blazing Star?

Marsh Blazing Star
  • Kidney and urinary complaints
  • Menstrual cramps (dysmenorrhea)
  • As a diuretic
  • Colic and digestive upset
  • Sore throat (traditional gargle)

Marsh blazing star (Liatris spicata) is a North American prairie plant whose root has a long history in folk medicine for urinary, menstrual, and digestive complaints. There is very little modern scientific evidence to confirm that it works or to define a safe dose, so it should be used cautiously and avoided in pregnancy and breastfeeding.

Liatris spicata · Asteraceae · Root · Dried root, tea, tincture, capsules

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

Marsh Blazing Star: dosing

There is no established or standardized dose for marsh blazing star. Traditional preparations used the dried root as a tea or tincture, but no reliable amount has been confirmed as safe or effective in modern research.If you choose to use a commercial product, follow the directions on the label and do not exceed them.

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

Read the full Marsh Blazing Star monograph & all interactions
Medication

About Tretinoin

What Is Tretinoin Used For?

Brand names: Vesanoid, Retin-A, Renova, Altreno

Tretinoin cream 0.02% is approved to help lessen the look of fine facial wrinkles in people who also follow a comprehensive skin care and sun-avoidance program — including daily sunscreen, protective clothing, and moisturizers.

It's important to know what tretinoin does not do: it will not erase wrinkles, reverse sun damage, repair deeply weathered skin, or restore younger-looking skin. It has also not been shown to help with coarse or deep wrinkles, rough skin texture, dark spots, or sagging skin.

Most-Reported Side Effects for Tretinoin

From FAERS, the FDA’s public side-effect reporting system (0 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Vomiting 498 reports
Rash 477 reports
Nausea 453 reports
Headache 434 reports
Diarrhea 414 reports
See full Tretinoin drug information
Keep checking

Other Drugs & Marsh Blazing Star

Browse every other medication we’ve checked against Marsh Blazing Star — 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
No interaction 2,829 drugs checked — show the list
Evidence & sources

Marsh Blazing Star References

The 5 references that drive our Marsh Blazing Star 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. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Mohler JL, Gomella LG, Crawford ED, et al. Phase II evaluation of coumarin (1,2-benzopyrone) in metastatic prostatic carcinoma. Prostate 1992;20:123-31. PubMed
  4. Marshall ME, Butler K, Fried A. Phase I evaluation of coumarin (1,2 benzopyrone) and cimetidine in patients with advanced malignancies. Mol Biother 1991;3:170-8.
  5. Goerz G, Wirth G, Maas B, et al. [Allergic contact dermatitis due to Asteraceae (Compositae). Cross reaction with Liatris spicata]. Derm Beruf Umwelt 1985;33:95-8.

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 Marsh Blazing Star and Tretinoin Together: Common Questions

Is it safe to take Marsh Blazing Star with Tretinoin?
We do not list a known interaction between Marsh Blazing Star and Tretinoin. 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 Marsh Blazing Star and Tretinoin have any of the same side effects?
Yes — our sources link each of them separately to 7 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.
Should I take Marsh Blazing Star and Tretinoin at the same time of day?
At least one FDA label for a product containing Tretinoin says to take it with food. If you take Marsh Blazing Star on an empty stomach out of habit, keep them separate and take Tretinoin with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Tretinoin products can differ — so check the directions on your own box. This is about absorption, not an interaction.
Does Tretinoin interact with any supplements?
Yes. Tretinoin has documented interactions with 52 supplements in our database — Marsh Blazing Star is not one of them. The Tretinoin 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 Tretinoin and Marsh Blazing Star?

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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.