Drug & supplement interaction

Schizonepeta + Phenytoin

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

No Known Interaction
The bottom line No known interaction

We found no known interaction between Schizonepeta 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

Schizonepeta 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 Schizonepeta 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.

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.

Schizonepeta safety at a glance

Schizonepeta overall Use caution Generally used in small amounts in traditional formulas, but high-quality safety data in humans are limited.
Pregnancy Avoid Safety in pregnancy has not been established, so it is best avoided.
Breastfeeding Avoid There is not enough information to consider it safe while breastfeeding.

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

Still wondering about combining Phenytoin and Schizonepeta? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Phenytoin

Interactions in our licensed database are recorded against drug classes, not just single drug names. Phenytoin is filed under 14 classifications — including cytochrome p450 2c8 (cyp2c8) substrates, cytochrome p450 2c9 (cyp2c9) inducers, anticonvulsants. Schizonepeta has documented interactions with 4 drug classes — the most serious being cytochrome p450 1a2 (cyp1a2) substrates (moderate), cytochrome p450 2d6 (cyp2d6) substrates (moderate) and cytochrome p450 2e1 (cyp2e1) substrates (moderate) — and none of Phenytoin’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Schizonepeta Does Interact With Other Medications

Schizonepeta has 797 moderate known drug interactions in our database — Phenytoin isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Schizonepeta

Covers the 2,830 medications we’ve checked against Schizonepeta. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests Schizonepeta 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.

  • Dizziness / Headache Additional detail

    Schizonepeta

    “There is currently a limited amount of information available about the adverse effects of schizonepeta. Orally, a specific combination product (Zemaphyte, Phytopharm Plc) containing schizonepeta and numerous other ingredients has been reported to cause nausea, vomiting, colic, dyspepsia, dizziness, headache, and hair loss.”

    Schizonepeta · Natural Medicines adverse-effect record, reported in alopecia.

    2 sources cited
    1. 12620. Fung D, Lau CB. Schizonepeta tenuifolia: chemistry, pharmacology, and clinical applications. J Clin Pharmacol 2002;42:30-6. PubMed
    2. 12626. Zhou S, Koh HL, Gao Y, et al. Herbal bioactivation: the good, the bad and the ugly. Life Sci 2004;74:935-68. PubMed

    “Orally, a specific combination product (Zemaphyte, Phytopharm Plc) containing schizonepeta and numerous other ingredients has been reported to cause dizziness and headache. However, it is unclear if these effects are due to schizonepeta or the other ingredients.”

    Schizonepeta · Natural Medicines adverse-effect record, reported in cluster headache.

    Phenytoin

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

  • Vomiting / Nausea Additional detail

    Schizonepeta

    “Orally, a specific combination product (Zemaphyte, Phytopharm Plc) containing schizonepeta and numerous other ingredients has been reported to cause nausea, vomiting, colic, and dyspepsia. However, it is unclear if these effects are due to schizonepeta or the other ingredients.”

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

    Phenytoin

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

Reported for Schizonepeta but not commonly for Phenytoin: stomach upset and hair loss.

Effects for Phenytoin come from the ADVERSE REACTIONS section of its FDA label; effects for Schizonepeta 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 Schizonepeta 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 Schizonepeta 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 Schizonepeta 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

One more smart check

Taking Schizonepeta as Part of a Dietary Supplement Product? Check It for Interactions

We hold 285 real supplement products containing Schizonepeta, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Schizonepeta. Even though Schizonepeta itself has no known interaction with Phenytoin, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Schizonepeta 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 Schizonepeta
Top half

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

29 days ago today
Medication Phenytoin
Top 25%

#687 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 Schizonepeta reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Schizonepeta 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 Schizonepeta

What is Schizonepeta?

  • Common cold and early-stage fever
  • Itchy skin rashes and hives
  • Sore throat
  • Headache
  • Measles and other skin eruptions (traditional use)

Schizonepeta is a mint-family herb long used in traditional Chinese medicine, usually as part of combination formulas for colds, fevers, and itchy skin conditions. Modern human evidence is very limited, so its benefits are not well proven. Talk to a pharmacist or doctor before using it, especially if you are pregnant, breastfeeding, or taking other medicines.

Schizonepeta tenuifolia · Lamiaceae · Dried aerial parts (stems and flower spikes); sometimes the essential oil · Dried herb for decoctions (tea), powders, capsules, and as part of traditional herbal formulas

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

Schizonepeta: dosing

There is no well-established standardized dose for Schizonepeta. In traditional Chinese medicine it is typically used as a dried herb in a decoction, often combined with other herbs, and amounts are tailored by a trained practitioner.For commercial supplements, follow the directions on the product label.

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

Read the full Schizonepeta 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 & Schizonepeta

Browse every other medication we’ve checked against Schizonepeta — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
797Moderate
0Minor
2,032No known interaction
Moderate

797 interactions

Showing 60 of 797 moderate interactions — see all 797 on the Schizonepeta page.

No interaction 2,032 drugs checked — show the list
Evidence & sources

Schizonepeta References

The 4 references that drive our Schizonepeta 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. Fung D, Lau CB. Schizonepeta tenuifolia: chemistry, pharmacology, and clinical applications. J Clin Pharmacol 2002;42:30-6. PubMed
  2. Zhou S, Koh HL, Gao Y, et al. Herbal bioactivation: the good, the bad and the ugly. Life Sci 2004;74:935-68. PubMed
  3. Fung AY, Look PC, Chong LY, et al. A controlled trial of traditional Chinese herbal medicine in Chinese patients with recalcitrant atopic dermatitis. Int J Dermatol 1999;38:387-92 . PubMed
  4. Bao B, Geng T, Cao Y, et al. Effects of schizonepetin on activity of mRNA expression of cytochrome P450 enzymes in rats. Int J Mol Sci. 2012;13(12):17006-18.

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 Schizonepeta and Phenytoin Together: Common Questions

Is it safe to take Schizonepeta with Phenytoin?
We do not list a known interaction between Schizonepeta 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 Schizonepeta and Phenytoin have any of the same side effects?
Yes — our sources link each of them separately to 4 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.
How was the Schizonepeta and Phenytoin combination checked?
Interactions in our licensed database are recorded against drug classes. Phenytoin is filed under 14 classifications, and Schizonepeta has documented interactions with 4 drug classes — none of Phenytoin's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Schizonepeta interact with any other medications?
Yes. Schizonepeta has 797 documented drug interactions in our database — Phenytoin is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Phenytoin interact with any supplements?
Yes. Phenytoin has documented interactions with 224 supplements in our database — Schizonepeta 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

Still Have a Question About Phenytoin and Schizonepeta?

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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.