Drug & supplement interaction

Ginger + Fosphenytoin

Fosphenytoin brand name: Cerebyx.

Minor Interaction
Medically reviewed by · Updated October 2026
The bottom line Minor

Ginger has a minor interaction with Fosphenytoin. Theoretically, ginger might increase the levels of CYP2C9 substrates.

Read the full interaction report
SeverityMinor
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Ginger and Fosphenytoin

Here is the interaction we found between these two, with the evidence behind it.

Minor

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

Why this applies to Fosphenytoin

Fosphenytoin falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES — the group Ginger interacts with.

Theoretically, ginger might increase the levels of CYP2C9 substrates.
In vitro research shows that ginger inhibits CYP2C9 activity. However, this interaction has not been reported in humans.
Severity Minor Likelihood Possible Evidence D

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the situation with ginger and fosphenytoin. Once it's given, fosphenytoin turns into phenytoin in your body, and phenytoin is cleared partly by a liver enzyme called CYP2C9. In a test tube, ginger seems to slow that enzyme down a bit. In theory, if that enzyme works slower, phenytoin could build up slightly and push you toward side effects like dizziness, drowsiness, unsteady walking, or slurred speech.

That said, this is only lab data, and it has never actually been reported in real people. Phenytoin is a narrow-window drug, so even small shifts can matter, but normal food and tea amounts of ginger are very unlikely to cause trouble. If you're using concentrated ginger supplements, just give your pharmacist or doctor a quick heads-up first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Husain I, Dale OR, Idrisi M, et al. Evaluation of the Herb-Drug Interaction (HDI) Potential of Zingiber officinale and Its Major Phytoconstituents. J Agric Food Chem. 2023;71(19):7521-7534.

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Ginger Also Interacts With Other Medications

Ginger has 875 moderate, 132 minor known drug interactions in our database — the Fosphenytoin one above is one of them. If you take anything else, check it against the full list below.

Moderate 875 Minor 132 No known interaction 1,823 (incl. Fosphenytoin)
Taking anything else?

Check Another of Your Medications Against Ginger

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

From our Q&A

Questions About Ginger or Fosphenytoin

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

This page covers Ginger only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Fosphenytoin page lists 205 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), American Hellebore (major), Arsenic (major), Beer (major) and Cesium (major).

By severity: 14 major · 172 moderate · 19 minor.

From our pharmacist’s overview on the Fosphenytoin page

“St. John's wort is the entry I would flag first with fosphenytoin (Cerebyx).”

Reviewed by 2 · Jul 18, 2026

Open the Fosphenytoin interaction page

One more smart check

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

We hold 9,640 real supplement products containing Ginger, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Ginger. Your product may carry other ingredients that interact with Fosphenytoin too, on top of Ginger — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Ginger and Fosphenytoin 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 Ginger
Top 5%

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

29 days ago today
Medication Fosphenytoin
Top 25%

#374 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.

Supplement

About Ginger

What is Ginger?

Ginger
  • Nausea and vomiting
  • Motion sickness
  • Morning sickness in pregnancy
  • Digestive upset
  • Menstrual cramps
  • Joint pain and inflammation

Ginger is a widely used culinary spice with a long history in traditional medicine, and it has the strongest evidence for helping with nausea and vomiting, including from motion sickness, pregnancy, and chemotherapy. It is generally safe in food and supplement amounts for most people, though it may cause mild stomach upset. Talk with your pharmacist or doctor before using ginger supplements, especially if you are pregnant, have a bleeding disorder, or take other medicines.

Read the full Ginger monograph & all interactions
Medication

About Fosphenytoin Injection

What Is Fosphenytoin Injection Used For?

Brand name: Cerebyx

Fosphenytoin Injection treats generalized tonic-clonic status epilepticus. This is a dangerous, prolonged seizure emergency. It is also used to prevent and treat seizures that happen during neurosurgery.

It can be used short-term in place of oral phenytoin. It should be used only when taking phenytoin by mouth is not possible.

See full Fosphenytoin Injection drug information
Keep checking

Other Drugs & Ginger

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

0Major
875Moderate
132Minor
1,822No known interaction
875 Moderate 132 Minor 1,822 No interaction
Moderate

875 interactions

Showing 60 of 875 moderate interactions — see all 875 on the Ginger page.

Minor

132 interactions

Showing 60 of 132 minor interactions — see all 132 on the Ginger page.

No interaction 1,822 drugs checked — show the list

We also checked Ginger against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 1,822 medications checked with no known interaction — see the full Ginger list.

See the full Ginger interactions page
See every supplement checked against Fosphenytoin, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Keep exploring
Ginger monograph › Uses, safety, and every drug interaction in one place Fosphenytoin supplement interactions › Every supplement checked against Fosphenytoin, ranked by severity Fosphenytoin Injection drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Ginger and Fosphenytoin Together: Common Questions

Can you take Ginger with Fosphenytoin?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Ginger and Fosphenytoin interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Fosphenytoin and Ginger?

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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.