Drug & supplement interaction

Turkey Tail Mushroom + Tamoxifen Citrate

Tamoxifen Citrate brand names: Nolvadex, Soltamox.

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

Tamoxifen Citrate falls into 2 drug categories that Turkey Tail Mushroom can interact with; the most serious is rated moderate. Theoretically, the polysaccharide peptide (PSP) component of turkey tail mushroom might interfere with the absorption of tamoxifen.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Turkey Tail Mushroom and Tamoxifen Citrate

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Turkey Tail Mushroom interacts with whole categories of medication. Tamoxifen Citrate falls into 2 of those categories, so it can interact with Turkey Tail Mushroom in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

TAMOXIFEN (Nolvadex)

1 of 2
Theoretically, the polysaccharide peptide (PSP) component of turkey tail mushroom might interfere with the absorption of tamoxifen.
Animal research suggests that PSP increases the time to reach maximum concentration of a single dose of tamoxifen by about 9.5 hours, or 228%. When repeated doses of tamoxifen were given, the time to reach maximum concentration was increased by about 5.6 hours, or 93%. However, PSP did not affect the maximum concentration or the area under the curve of tamoxifen.
Severity Moderate 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 honest picture with tamoxifen and turkey tail mushroom: the concern is small and comes only from animal studies, not people. In those studies, the PSP part of turkey tail slowed down how quickly tamoxifen reached its peak level in the blood. Importantly, it did not change the total amount absorbed or the overall exposure. So the medicine still got into the body, it just took a bit longer to peak.

For day-to-day use, this is mostly theoretical, and tamoxifen is taken long term, so a slightly slower peak from one dose isn't likely to change how well it works. Still, because tamoxifen is such an important breast cancer medicine, I'd run any turkey tail supplement past your oncologist or pharmacist first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Razmovski-Naumovski V, Kimble B, Laurenti D, Nammi S, Norimoto H, Chan K. Polysaccharide peptide extract from Coriolus versicolor increased T(max) of tamoxifen and maintained biochemical serum parameters, with no change in the metabolism of tamoxifen in t
Minor

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

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Why this applies to Tamoxifen Citrate

Tamoxifen Citrate falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES — the group Turkey Tail Mushroom interacts with.

Theoretically, the polysaccharide peptide (PSP) component of turkey tail mushroom might inhibit CYP2C9.
Laboratory research suggests that the PSP component of turkey tail mushroom dose-dependently inhibits CYP2C9. Theoretically, taking PSP with drugs metabolized by CYP2C9 might increase drug levels and the risk of adverse effects. However, this 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 short version: a compound in turkey tail called PSP has been shown in lab dishes to slow down an enzyme called CYP2C9, which is one of the enzymes that helps process tamoxifen. In theory, if that enzyme runs slower, more tamoxifen could linger in your body. That might mean a bit more of the usual tamoxifen effects, like hot flashes, leg cramps, or nausea.

I want to be honest, though: this is only a theoretical concern. It has never actually been reported in people, and the evidence comes from test-tube studies, not real patients. Still, because tamoxifen is such an important cancer medicine, please loop in your oncologist or pharmacist before adding turkey tail. Don't start or stop anything on your own.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Yeung JH and Or PM. Polysaccharide peptides from Coriolus versicolor competitively inhibit tolbutamide 4-hydroxylation in specific human CYP2C9 isoform and pooled human liver microsomes. Phytomedicine 2011;18(13):1170-5. PubMed

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

Turkey Tail Mushroom Also Interacts With Other Medications

Turkey Tail Mushroom has 87 moderate, 100 minor known drug interactions in our database — the Tamoxifen Citrate one above is among them. If you take anything else, check it against the full list below.

Moderate 87 Minor 100 No known interaction 2,643 (incl. Tamoxifen Citrate)
Taking anything else?

Check Another of Your Medications Against Turkey Tail Mushroom

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

From our Q&A

Questions About Turkey Tail Mushroom or Tamoxifen Citrate

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Turkey Tail Mushroom or Tamoxifen Citrate, 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 Tamoxifen Citrate

This page covers Turkey Tail Mushroom only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Tamoxifen Citrate page lists 210 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), Arsenic (major), Beer (major) and Cesium (major).

By severity: 11 major · 166 moderate · 33 minor.

From our pharmacist’s overview on the Tamoxifen Citrate page

“Tamoxifen (Nolvadex, Soltamox) often stands between a breast cancer patient and a recurrence, so the stakes on this page run higher than usual. Eleven of the 210 supplements and herbs on file carry a major rating, and those eleven deserve your attention ahead of everything else.”

Reviewed by 2 · Jul 18, 2026

Open the Tamoxifen Citrate interaction page

How much people look this up

Where Turkey Tail Mushroom and Tamoxifen Citrate 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 Turkey Tail Mushroom
Top half

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

29 days ago today
Medication Tamoxifen Citrate
Top 5%

#132 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 Turkey Tail Mushroom

What is Turkey Tail Mushroom?

Turkey Tail Mushroom
  • Immune support
  • Used alongside cancer care
  • Gut and digestive health
  • General wellness and energy
  • Antioxidant support

Turkey tail is a woodland mushroom rich in polysaccharides like beta-glucans, and it is mainly used to support the immune system. Some of its purified extracts (PSK and PSP) have been studied as add-on treatments alongside conventional cancer therapy in Asia, but evidence for everyday supplement use is limited. It is generally well tolerated, but talk to your pharmacist or doctor before using it, especially if you have a health condition or take other medicines.

Read the full Turkey Tail Mushroom monograph & all interactions
Medication

About Tamoxifen

What Is Tamoxifen Used For?

Brand names: Nolvadex, Soltamox

Tamoxifen is used to treat metastatic breast cancer (breast cancer that has spread) in both women and men, and as adjuvant (after-surgery) therapy for early-stage breast cancer in women. It also reduces the occurrence of cancer in the opposite breast when used as adjuvant therapy.

In women with ductal carcinoma in situ (DCIS) — a very early, non-invasive form of breast cancer — tamoxifen is used after breast surgery and radiation to reduce the risk of developing invasive breast cancer. It is also approved to reduce the incidence of breast cancer in women who are at high risk but have not yet been diagnosed. Soltamox (oral solution) is specifically indicated for all of these uses in adult patients.

See full Tamoxifen drug information Tamoxifen Citrate NDC codes and packages
Keep checking

Other Drugs & Turkey Tail Mushroom

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

0Major
87Moderate
100Minor
2,642No known interaction
87 Moderate 100 Minor 2,642 No interaction
Moderate

87 interactions

Showing 60 of 87 moderate interactions — see all 87 on the Turkey Tail Mushroom page.

Minor

100 interactions

Showing 60 of 100 minor interactions — see all 100 on the Turkey Tail Mushroom page.

No interaction 2,642 drugs checked — show the list

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

Showing the 60 most looked-up of 2,642 medications checked with no known interaction — see the full Turkey Tail Mushroom list.

See the full Turkey Tail Mushroom interactions page
See every supplement checked against Tamoxifen Citrate, 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
Turkey Tail Mushroom monograph › Uses, safety, and every drug interaction in one place Tamoxifen Citrate supplement interactions › Every supplement checked against Tamoxifen Citrate, ranked by severity Tamoxifen drug information › The full plain-English guide to this medication Tamoxifen Citrate NDC codes and packages › Every package, labeler and price in the FDA directory 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 Turkey Tail Mushroom and Tamoxifen Citrate Together: Common Questions

Can you take Turkey Tail Mushroom with Tamoxifen Citrate?
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.
Why are there 2 interactions listed for Turkey Tail Mushroom and Tamoxifen Citrate?
Tamoxifen Citrate belongs to more than one drug category, and Turkey Tail Mushroom interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Turkey Tail Mushroom and Tamoxifen Citrate 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 Tamoxifen Citrate and Turkey Tail Mushroom?

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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.