Drug & supplement interaction

Puravive + Phenytoin

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

Moderate Interaction
Medically reviewed by · Updated February 2024
The bottom line Moderate

Puravive has a moderate interaction with Phenytoin. Puravive contains quercetin, which has been shown in studies to mildly inhibit the CYP2C9 metabolizing enzyme.

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

Puravive and Phenytoin

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

Moderate

Cytochrome P450 2C9 (Cyp2C9) Substrates

Why this applies to Phenytoin

Phenytoin falls under Cytochrome P450 2C9 (Cyp2C9) Substrates — the group Puravive interacts with.

Puravive contains quercetin, which has been shown in studies to mildly inhibit the CYP2C9 metabolizing enzyme. This inhibition could potentially increase the risk of side effects from drugs. A small clinical trial with healthy volunteers found that taking 500 mg of quercetin twice daily for 10 days before using diclofenac, a drug metabolized by CYP2C9, increased diclofenac plasma levels by 75% and extended its half-life by 32.5% (source: https://pubmed.ncbi.nlm.nih.gov/29168292/). Combining quercetin with drugs metabolized by CYP2C9 could increase the risk of side effects, so caution is advised.
Severity Moderate Likelihood Possible Evidence C

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 thing with phenytoin: your liver relies heavily on an enzyme called CYP2C9 to clear it out. Puravive contains quercetin, which can mildly slow that enzyme down. Since phenytoin is an active drug (not a prodrug), slowing its breakdown could let it build up in your blood and push your levels a little higher.

Phenytoin is one of those drugs where small changes matter a lot. Higher levels can bring on things like dizziness, unsteady walking, slurred speech, blurred or double vision, and drowsiness. The evidence here is limited and comes from a study using a different drug, so this is more a caution than a sure thing. Please don't stop or change anything on your own. Check with your pharmacist or doctor first, since they may want to watch your phenytoin level.

Contact Dr. Brian directly if you have additional questions on this interaction

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

Puravive Also Interacts With Other Medications

Puravive has 356 moderate, 881 minor known drug interactions in our database — the Phenytoin one above is one of them. If you take anything else, check it against the full list below.

Moderate 356 Minor 881 No known interaction 1,593 (incl. Phenytoin)
Taking anything else?

Check Another of Your Medications Against Puravive

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

From our Q&A

Questions About Puravive 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 Puravive 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 Puravive 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 Puravive 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 Puravive
Steady interest

#1,379 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Phenytoin
Steady interest

#1,761 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 Puravive

What is Puravive?

Puravive
  • Weight management
  • Metabolism support
  • Energy levels
  • General wellness
  • Stress and brain health

Puravive is a branded, multi-ingredient capsule marketed mainly for weight loss by claiming to boost brown fat activity, but there is no published, independent clinical research showing the product itself works for this purpose. Some individual ingredients have been studied in laboratory or small human studies, but those results do not prove the finished blend is safe or effective. Talk to a pharmacist or doctor before trying it, especially if you have health conditions or take medications.

Read the full Puravive 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.

See full Phenytoin drug information
Keep checking

Other Drugs & Puravive

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

0Major
356Moderate
881Minor
1,592No known interaction
356 Moderate 881 Minor 1,592 No interaction
Moderate

356 interactions

Showing 60 of 356 moderate interactions — see all 356 on the Puravive page.

Minor

881 interactions

Showing 60 of 881 minor interactions — see all 881 on the Puravive page.

No interaction 1,592 drugs checked — show the list

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

Showing the 60 most looked-up of 1,592 medications checked with no known interaction — see the full Puravive list.

See the full Puravive interactions page
See every supplement checked against Phenytoin, 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
Puravive monograph › Uses, safety, and every drug interaction in one place Phenytoin supplement interactions › Every supplement checked against Phenytoin, ranked by severity Phenytoin 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 Puravive and Phenytoin Together: Common Questions

Can you take Puravive with Phenytoin?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Puravive and Phenytoin interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Phenytoin and Puravive?

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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.