Drug & supplement interaction

Marsh Blazing Star + Dextromethorphan HBr, Guaifenesin

Dextromethorphan HBr, Guaifenesin brand names: Vicks Formula 44E Cough & Chest Congestion Relief, Pediatric Vicks Formula 44e Cough & Chest Congesti.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Marsh Blazing Star and Dextromethorphan HBr, Guaifenesin 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.

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Interaction report

Marsh Blazing Star and Dextromethorphan HBr, Guaifenesin

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 Dextromethorphan HBr, Guaifenesin 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 Dextromethorphan HBr, Guaifenesin, 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 Dextromethorphan HBr, Guaifenesin and Marsh Blazing Star? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Marsh Blazing Star Itself Has Been Linked To

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

  • Liver problems / An allergic reaction Worth acting on Additional detail

    “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.
  • Trouble sleeping / Dizziness / Diarrhea / A skin rash / Vomiting / Nausea Additional detail

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

Everything above comes from the Natural Medicines adverse-effect record for Marsh Blazing Star — expand a row for the licensed statement it rests on. We haven’t matched Dextromethorphan HBr, Guaifenesin to its FDA label in our system yet, so we can’t compare its own side-effect list here — the leaflet that comes with your prescription is the authoritative list for Dextromethorphan HBr, Guaifenesin.

Everything else you take

See Every Supplement That Interacts With Dextromethorphan HBr, Guaifenesin

This page covers Marsh Blazing Star only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dextromethorphan HBr, Guaifenesin page lists 171 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 4 major · 125 moderate · 42 minor.

From our pharmacist’s overview on the Dextromethorphan HBr, Guaifenesin page

“A bad cough tends to hit when supplements are already on the counter, and anyone reaching for Vicks Formula 44E (dextromethorphan HBr and guaifenesin) should treat this list with real care, since 4 of its 171 entries carry a major rating. Two themes dominate.”

Reviewed by 2 · Jul 18, 2026

Open the Dextromethorphan HBr, Guaifenesin interaction page

How much people look this up

Where Marsh Blazing Star and Dextromethorphan HBr, Guaifenesin 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

#1,171 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Dextromethorphan HBr, Guaifenesin
Top half

#942 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 20, 2026. The Marsh Blazing Star and Dextromethorphan HBr, Guaifenesin 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 Dextromethorphan HBr, Guaifenesin

Most-Reported Side Effects for Dextromethorphan HBr, Guaifenesin

From FAERS, the FDA’s public side-effect reporting system (1,675 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Dyspnea 140 reports
Pneumonia 123 reports
Nausea 120 reports
Cough 119 reports
Fatigue 118 reports
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 Dextromethorphan HBr, Guaifenesin Together: Common Questions

Is it safe to take Marsh Blazing Star with Dextromethorphan HBr, Guaifenesin?
We do not list a known interaction between Marsh Blazing Star and Dextromethorphan HBr, Guaifenesin. 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.
Does Dextromethorphan HBr, Guaifenesin interact with any supplements?
Yes. Dextromethorphan HBr, Guaifenesin has documented interactions with 171 supplements in our database — Marsh Blazing Star is not one of them. The Dextromethorphan HBr, Guaifenesin 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 Dextromethorphan HBr, Guaifenesin 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.