Drug & supplement interaction

Vitamin E + Estramustine Phosphate Sodium

Estramustine Phosphate Sodium brand name: Emcyt.

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

Vitamin E has a moderate interaction with Estramustine Phosphate Sodium. Theoretically, antioxidant effects of vitamin E might reduce the effectiveness of alkylating agents.

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

Vitamin E and Estramustine Phosphate Sodium

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

Moderate

ALKYLATING AGENTS

Why this applies to Estramustine Phosphate Sodium

Estramustine Phosphate Sodium falls under ALKYLATING AGENTS — the group Vitamin E interacts with.

Theoretically, antioxidant effects of vitamin E might reduce the effectiveness of alkylating agents.
There's concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin E have on chemotherapy. Advise patients to consult their oncologist before using vitamin E supplements, especially in high doses.
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 thinking behind this one. Some chemotherapy drugs are believed to work partly by creating unstable molecules (free radicals) that damage cancer cells. Because vitamin E is an antioxidant, the worry is that high doses might mop up those free radicals and, in theory, make a drug like estramustine (Emcyt) less effective at fighting your prostate cancer.

I want to be honest: this is a theoretical concern based on how these drugs behave, not on solid human studies. Some researchers even argue antioxidants could help. We just don't know for sure. Everyday food amounts of vitamin E are very unlikely to matter, but concentrated high-dose supplements are a different story. Please loop in your oncologist or pharmacist before adding any vitamin E while you're on estramustine.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  2. Prasad KN. Rationale for using high-dose multiple dietary antioxidants as an adjunct to radiation therapy and chemotherapy. J Nutr 2004;134:3182S-3S. PubMed
  3. Conklin KA. Cancer chemotherapy and antioxidants. J Nutr 2004;134:3201S-3204S. 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

Vitamin E Also Interacts With Other Medications

Vitamin E has 762 moderate, 1 minor known drug interactions in our database — the Estramustine Phosphate Sodium one above is one of them. If you take anything else, check it against the full list below.

Moderate 762 Minor 1 No known interaction 2,067 (incl. Estramustine Phosphate Sodium)
Taking anything else?

Check Another of Your Medications Against Vitamin E

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

Everything else you take

See Every Supplement That Interacts With Estramustine Phosphate Sodium

This page covers Vitamin E only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Estramustine Phosphate Sodium page lists 24 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Acerola (moderate), Alpha-lipoic Acid (moderate), Coenzyme Q10 (moderate) and Coffee Charcoal (moderate).

By severity: 1 major · 14 moderate · 9 minor.

From our pharmacist’s overview on the Estramustine Phosphate Sodium page

“Estramustine phosphate sodium (Emcyt) is an oral chemotherapy for advanced prostate cancer, so supplements that weaken it carry real weight, and this list of 24 ingredients warrants genuine care. Nearly everything here does one of two things: fiber-heavy products like psyllium and various gums can keep the capsule from being absorbed p…”

Reviewed by 2 · Jul 18, 2026

Open the Estramustine Phosphate Sodium interaction page

One more smart check

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

We hold 22,182 real supplement products containing Vitamin E, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Vitamin E. Your product may carry other ingredients that interact with Estramustine Phosphate Sodium too, on top of Vitamin E — 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 Vitamin E and Estramustine Phosphate Sodium 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 Vitamin E
Top 10

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

29 days ago today
Medication Estramustine Phosphate Sodium
Steady interest

#1,467 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 Vitamin E

What is Vitamin E?

Vitamin E
  • General antioxidant support
  • Skin and hair care
  • Heart health
  • Eye health (age-related conditions)
  • Immune support

Vitamin E is an essential fat-soluble vitamin and antioxidant that most people get in adequate amounts from a normal diet. Supplements can help correct a true deficiency, but high-dose vitamin E has not been clearly proven to prevent heart disease or cancer and may carry risks. Talk to your pharmacist or doctor before taking high doses.

Read the full Vitamin E monograph & all interactions
Medication

About Estramustine

What Is Estramustine Used For?

Brand name: Emcyt

  • Estramustine is used to treat prostate cancer that has worsened or has spread to other parts of the body. Estramustine is in a class of medications called antimicrotubule agents. It works by stopping the growth and spread of cancer cells.

See full Estramustine drug information
Keep checking

Other Drugs & Vitamin E

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

0Major
762Moderate
1Minor
2,066No known interaction
762 Moderate 1 Minor 2,066 No interaction
Moderate

762 interactions

Showing 60 of 762 moderate interactions — see all 762 on the Vitamin E page.

Minor

1 interaction

No interaction 2,066 drugs checked — show the list

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

Showing the 60 most looked-up of 2,066 medications checked with no known interaction — see the full Vitamin E list.

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

Can you take Vitamin E with Estramustine Phosphate Sodium?
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 Vitamin E and Estramustine Phosphate Sodium 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 Estramustine Phosphate Sodium and Vitamin E?

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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.