Drug & supplement interaction

Marsh Blazing Star + Phenytoin

Phenytoin brand names: Dilantin Kapseals, Dilantin, Di-Phen, Dilantin Infatabs, Phenytek, and others.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 20, 2026
The bottom line No known interaction

We found no known interaction between Marsh Blazing Star and Phenytoin 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

Marsh Blazing Star and Phenytoin

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 Phenytoin 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 Phenytoin, 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 Phenytoin 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 Phenytoin 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. 2 of them are worth acting on rather than waiting out — marked below.

  • Liver problems / An allergic reaction 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.

    Phenytoin

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

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

    Marsh Blazing Star

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

    Phenytoin

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

Reported for Marsh Blazing Star but not commonly for Phenytoin: diarrhea.

Effects for Phenytoin 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. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

From our Q&A

Questions About Marsh Blazing Star or Phenytoin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Marsh Blazing Star or Phenytoin, 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 Phenytoin

This page covers Marsh Blazing Star only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Phenytoin page lists 224 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Beer (major), Gamma-hydroxybutyrate (ghb) (major) and Kava (major).

By severity: 9 major · 187 moderate · 28 minor.

From our pharmacist’s overview on the Phenytoin page

“Phenytoin (Dilantin) is a seizure medicine with a narrow therapeutic index, meaning small changes in its blood level can bring seizures back or tip over into toxicity, so I treat its supplement list with real seriousness. The biggest group, 78 ingredients, piles on sedation, and alcohol, kava, and GHB all rate major for exactly that re…”

Reviewed by 2 · Jul 18, 2026

Open the Phenytoin interaction page

How much people look this up

Where Marsh Blazing Star and Phenytoin 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

#1,351 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Phenytoin
Top 25%

#496 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 Phenytoin 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 Phenytoin

What Is Phenytoin Used For?

Brand names: Dilantin Kapseals, Dilantin, Di-Phen, Dilantin Infatabs, Phenytek, Dilantin injection

Phenytoin is used to treat and prevent seizures. The specific types covered depend on the formulation. Oral extended-release capsules (including Phenytek), chewable tablets (including Dilantin Infatabs and Phenytoin Infatabs), and oral suspension (including Dilantin-125) are used for tonic-clonic (grand mal) and psychomotor (temporal lobe) seizures; most oral forms also cover prevention and treatment of seizures occurring during or after neurosurgery. Chewable tablets and some capsule formulations also cover complex partial seizures.

Parenteral (injectable) phenytoin sodium is used for generalized tonic-clonic status epilepticus (a prolonged, life-threatening seizure emergency) and for prevention and treatment of seizures during neurosurgery. The IV form can also substitute short-term for oral phenytoin when a patient cannot take it by mouth.

Most-Reported Side Effects for Phenytoin

From FAERS, the FDA’s public side-effect reporting system (40,278 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Convulsion 3,522 reports
Seizure 3,095 reports
Toxicity to various agents 1,888 reports
Fall 1,604 reports
Dizziness 1,539 reports
See full Phenytoin 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
2,829 No interaction
No interaction 2,829 drugs checked — show the list

We also checked Marsh Blazing Star 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 Marsh Blazing Star list.

See the full Marsh Blazing Star interactions page
See every supplement checked against Phenytoin, ranked by severity
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 Phenytoin Together: Common Questions

Is it safe to take Marsh Blazing Star with Phenytoin?
We do not list a known interaction between Marsh Blazing Star and Phenytoin. 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 Phenytoin 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.
Does Phenytoin interact with any supplements?
Yes. Phenytoin has documented interactions with 224 supplements in our database — Marsh Blazing Star is not one of them. The Phenytoin 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

Marsh Blazing Star monograph Uses, safety profile, and every drug interaction in one place Phenytoin drug information The full plain-English guide to this medication Phenytoin supplement interactions Every supplement checked against Phenytoin, 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 5 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Phenytoin 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.