Drug & supplement interaction

Apple Polyphenols + Ketoconazole

Ketoconazole brand name: Nizoral.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Apple Polyphenols and Ketoconazole 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

Apple Polyphenols and Ketoconazole

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 Ketoconazole and Apple Polyphenols 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.

Apple Polyphenols safety at a glance

Apple Polyphenols overall Use caution Likely safe in food amounts; concentrated supplements are less studied for long-term use.
Pregnancy Use caution Apples as food are fine, but concentrated extracts have not been studied in pregnancy, so avoid supplements unless your doctor approves.
Breastfeeding Use caution There is not enough information on concentrated extracts during breastfeeding, so caution is advised.

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

Still wondering about combining Ketoconazole and Apple Polyphenols? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Ketoconazole

Interactions in our licensed database are recorded against drug classes, not just single drug names. Ketoconazole is filed under 8 classifications — including antifungals, cytochrome p450 2c19 (cyp2c19) inhibitors, cytochrome p450 2c9 (cyp2c9) inhibitors. Apple Polyphenols has documented interactions with 1 drug class — the most serious being insulin (moderate) — and none of Ketoconazole’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

Apple Polyphenols Does Interact With Other Medications

Apple Polyphenols has 13 moderate known drug interactions in our database — Ketoconazole 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 Apple Polyphenols

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

What to actually watch for

No Interaction Found — But Data Suggests Apple Polyphenols and Ketoconazole 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.

  • Diarrhea Additional detail

    Apple Polyphenols

    “Orally, taking 600 mg apple polyphenols was reported to cause diarrhea and loose stools in one clinical study.”

    Apple Polyphenols · Natural Medicines adverse-effect record, reported in diarrhea.

    1 source cited
    1. 94863. Nagasako-Akazome Y, Kanda T, Ohtake Y, Shimasaki H, Kobayashi T. Apple polyphenols influence cholesterol metabolism in healthy subjects with relatively high body mass index. J Oleo Sci. 2007;56(8):417-28. PubMed

    Ketoconazole

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

  • Headache Additional detail

    Apple Polyphenols

    “Orally, apple polyphenols seem to be well tolerated. Some clinical studies have reported no adverse effects with apple polyphenols, while mild gastrointestinal effects, nasopharyngitis, and headache have been reported in other studies.”

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

    4 sources cited
    1. 94855. Akazome Y, Kametani N, Kanda T, et al. Evaluation of safety of excessive intake and efficacy of long-term intake of beverages containing apple polyphenols. J Oleo Sci. 2010;59(6):321-38. PubMed
    2. 94863. Nagasako-Akazome Y, Kanda T, Ohtake Y, Shimasaki H, Kobayashi T. Apple polyphenols influence cholesterol metabolism in healthy subjects with relatively high body mass index. J Oleo Sci. 2007;56(8):417-28. PubMed
    3. 94869. Tenore GC, Caruso D, Buonomo G, et al. A Healthy Balance of Plasma Cholesterol by a Novel Annurca Apple-Based Nutraceutical Formulation: Results of a Randomized Trial. J Med Food. 2017;20(3):288-300. PubMed
    4. 102020. Saarenhovi M, Salo P, Scheinin M, et al. The effect of an apple polyphenol extract rich in epicatechin and flavan-3-ol oligomers on brachial artery flow-mediated vasodilatory function in volunteers with elevated blood pressure. Nutr. J 2017;16(1):73. PubMed

    “Orally, taking apple polyphenols may cause headache in some patients. In one clinical trial, around 26% of patients taking apple polyphenols 330 mg daily for 4 weeks reported headaches, although this adverse effect was also reported in nearly 24% of patients taking placebo.”

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

    1 source cited
    1. 102020. Saarenhovi M, Salo P, Scheinin M, et al. The effect of an apple polyphenol extract rich in epicatechin and flavan-3-ol oligomers on brachial artery flow-mediated vasodilatory function in volunteers with elevated blood pressure. Nutr. J 2017;16(1):73. PubMed

    Ketoconazole

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

Effects for Ketoconazole come from the ADVERSE REACTIONS section of its FDA label; effects for Apple Polyphenols 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 Apple Polyphenols or Ketoconazole

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

This page covers Apple Polyphenols only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ketoconazole page lists 182 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Grapefruit (major), Siberian Cocklebur (major) and St. John's Wort (major).

By severity: 6 major · 135 moderate · 41 minor.

From our pharmacist’s overview on the Ketoconazole page

“Ketoconazole (Nizoral) is already hard on the liver, so treat its 182 interacting supplements with genuine care, starting with the six rated major. Most of the list runs through CYP3A4, the liver enzyme ketoconazole strongly blocks, so it can raise levels of over a hundred herbal ingredients, while grapefruit pushes ketoconazole itself…”

Reviewed by 2 · Jul 18, 2026

Open the Ketoconazole interaction page

How much people look this up

Where Apple Polyphenols and Ketoconazole 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 Apple Polyphenols
Steady interest

#1,039 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Ketoconazole
Steady interest

#2,081 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 Apple Polyphenols reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Apple Polyphenols and Ketoconazole 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 Apple Polyphenols

What is Apple Polyphenols?

Apple Polyphenols
  • High cholesterol
  • High blood pressure
  • Weight management
  • Antioxidant support
  • Blood sugar support
  • Skin health (topical)

Apple polyphenols are antioxidant plant compounds taken from apples and marketed for heart, weight, and blood sugar health. Early research is interesting, but there is not enough reliable human evidence to confirm these benefits. They appear generally safe in food-like amounts, but talk with your pharmacist or doctor before using concentrated supplements.

Malus domestica · Rosaceae · Fruit, peel, and pomace (sometimes unripe apples) · Capsules, tablets, powders, and standardized extracts

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

Apple Polyphenols: dosing

There is no standardized, well-established dose for apple polyphenols. Products vary widely in how much polyphenol they contain.The best approach is to follow the directions on the product label and not exceed the suggested amount.

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

Read the full Apple Polyphenols monograph & all interactions
Medication

About Ketoconazole

What Is Ketoconazole Used For?

Brand name: Nizoral

Ketoconazole 2% shampoo and foam are used to treat tinea versicolor (also called pityriasis versicolor) — a fungal infection caused by Pityrosporum orbiculare (also known as Malassezia furfur), a yeast that naturally lives on the skin.

This infection creates light or dark patches, most often on the trunk, neck, arms, and upper thighs. Even after the fungus is cleared, those skin patches may take months to return to their normal color — that's normal, and depends on your skin type and sun exposure. Tinea versicolor can also come back, since the fungus lives on healthy skin even when there's no active infection.

Most-Reported Side Effects for Ketoconazole

From FAERS, the FDA’s public side-effect reporting system (0 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Pruritus 984 reports
Fatigue 975 reports
Nausea 873 reports
Rash 858 reports
Diarrhea 814 reports
See full Ketoconazole drug information
Keep checking

Other Drugs & Apple Polyphenols

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

0Major
13Moderate
0Minor
2,816No known interaction
Moderate

13 interactions

No interaction 2,816 drugs checked — show the list
Evidence & sources

Apple Polyphenols References

The 10 references that drive our Apple Polyphenols 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. Akazome Y, Kametani N, Kanda T, et al. Evaluation of safety of excessive intake and efficacy of long-term intake of beverages containing apple polyphenols. J Oleo Sci. 2010;59(6):321-38. PubMed
  2. Auclair S, Chironi G, Milenkovic D, et al. The regular consumption of a polyphenol-rich apple does not influence endothelial function: a randomised double-blind trial in hypercholesterolemic adults. Eur J Clin Nutr. 2010;64(10):1158-65. PubMed
  3. Deley G, Guillemet D, Allaert FA, Babault N. An Acute Dose of Specific Grape and Apple Polyphenols Improves Endurance Performance: A Randomized, Crossover, Double-Blind versus Placebo Controlled Study. Nutrients. 2017;9(8). pii: E917. PubMed
  4. Kamimura A, Takahashi T, Watanabe Y. Investigation of topical application of procyanidin B-2 from apple to identify its potential use as a hair growing agent. Phytomedicine. 2000;7(6):529-36. PubMed
  5. Kishi K, Saito M, Saito T, et al. Clinical efficacy of apple polyphenol for treating cedar pollinosis. Biosci Biotechnol Biochem. 2005;69(4):829-32. PubMed
  6. Nagasako-Akazome Y, Kanda T, Ohtake Y, Shimasaki H, Kobayashi T. Apple polyphenols influence cholesterol metabolism in healthy subjects with relatively high body mass index. J Oleo Sci. 2007;56(8):417-28. PubMed
  7. Takahashi T, Kamimura A, Kagoura M, et al. Investigation of the topical application of procyanidin oligomers from apples to identify their potential use as a hair-growing agent. J Cosmet Dermatol. 2005;4(4):245-9. PubMed
  8. Tenore GC, Caruso D, Buonomo G, et al. A Healthy Balance of Plasma Cholesterol by a Novel Annurca Apple-Based Nutraceutical Formulation: Results of a Randomized Trial. J Med Food. 2017;20(3):288-300. PubMed
  9. Saarenhovi M, Salo P, Scheinin M, et al. The effect of an apple polyphenol extract rich in epicatechin and flavan-3-ol oligomers on brachial artery flow-mediated vasodilatory function in volunteers with elevated blood pressure. Nutr. J 2017;16(1):73. PubMed
  10. Prpa EJ, Corpe CP, Atkinson B, et al. Apple polyphenol-rich drinks dose-dependently decrease early-phase postprandial glucose concentrations following a high-carbohydrate meal: a randomized controlled trial in healthy adults and in vitro studies. J Nutr B PubMed

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 Apple Polyphenols and Ketoconazole Together: Common Questions

Is it safe to take Apple Polyphenols with Ketoconazole?
We do not list a known interaction between Apple Polyphenols and Ketoconazole. 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 Apple Polyphenols and Ketoconazole have any of the same side effects?
Yes — our sources link each of them separately to 2 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 Apple Polyphenols and Ketoconazole combination checked?
Interactions in our licensed database are recorded against drug classes. Ketoconazole is filed under 8 classifications, and Apple Polyphenols has documented interactions with 1 drug class — none of Ketoconazole'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 Apple Polyphenols interact with any other medications?
Yes. Apple Polyphenols has 13 documented drug interactions in our database — Ketoconazole 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 Ketoconazole interact with any supplements?
Yes. Ketoconazole has documented interactions with 182 supplements in our database — Apple Polyphenols is not one of them. The Ketoconazole 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 Ketoconazole and Apple Polyphenols?

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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.