Drug & supplement interaction

Palm Oil + Letrozole

Letrozole brand name: Femara.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Palm Oil and Letrozole 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.

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Interaction report

Palm Oil and Letrozole

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 Letrozole and Palm Oil 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.

Palm Oil safety at a glance

Palm Oil overall Use caution Generally safe as a food, but high in saturated fat, so use in moderation.
Pregnancy Possibly Safe When used orally and appropriately in medicinal amounts. Diets rich in palm oil or supplemented with palm oil have been used safely during the third trimester o... Read the full pregnancy detail
Breastfeeding Use caution Acceptable as part of a normal diet; supplement safety is not well established.

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Letrozole and Palm Oil? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Letrozole

Interactions in our licensed database are recorded against drug classes, not just single drug names. Letrozole is filed under 4 classifications — including aromatase inhibitors, cytochrome p450 2c19 (cyp2c19) inhibitors, cytochrome p450 3a4 (cyp3a4) substrates. Palm Oil has documented interactions with 1 drug class — the most serious being anticoagulant/antiplatelet drugs (moderate) — and none of Letrozole’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

Palm Oil Does Interact With Other Medications

Palm Oil has 122 moderate known drug interactions in our database — Letrozole isn’t one of them. If you take anything else, check it against the full list below.

Moderate 122 No known interaction 2,708 (incl. Letrozole)
Taking anything else?

Check Another of Your Medications Against Palm Oil

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

What to actually watch for

What Letrozole’s Own FDA Label Lists

This is not an interaction — none of it involves Palm Oil. These are the most notable effects listed in the ADVERSE REACTIONS section of Letrozole’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you take both. One of them is worth acting on rather than waiting out — marked below.

  • Bleeding or bruising Worth acting on
  • Flushing
  • Sweating
  • Joint pain
  • Muscle pain
  • Swelling
  • Tiredness
  • Dizziness
  • Headache
  • Nausea

From the ADVERSE REACTIONS section of the FDA label for Letrozole. Read the label on DailyMed › Palm Oil’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Palm Oil side to compare — that is a limit of the record, not a statement that Palm Oil has no side effects.

Special populations

Palm Oil in Pregnancy & Breastfeeding

Pregnancy Possibly Safe

When used orally and appropriately in medicinal amounts. Diets rich in palm oil or supplemented with palm oil have been used safely during the third trimester of pregnancy.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

From our Q&A

Questions About Palm Oil or Letrozole

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

This page covers Palm Oil only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Letrozole page lists 142 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), 7-methoxyflavone (moderate) and Acacia Rigidula (moderate).

By severity: 3 major · 99 moderate · 40 minor.

From our pharmacist’s overview on the Letrozole page

“Letrozole (Femara) is prescribed to keep hormone-driven breast cancer from returning, so a supplement that shifts its blood level can quietly undercut treatment. Give this list of 142 ingredients genuine respect, and learn the three major entries first.”

Reviewed by 2 · Jul 18, 2026

Open the Letrozole interaction page

One more smart check

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

We hold 55 real supplement products containing Palm Oil, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Palm Oil. Even though Palm Oil itself has no known interaction with Letrozole, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Palm Oil and Letrozole 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 Palm Oil
Top half

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

29 days ago today
Medication Letrozole
Top 5%

#50 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 Palm Oil reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Palm Oil and Letrozole records this page draws on were last updated July 11, 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 Palm Oil

What is Palm Oil?

  • Cooking and food preparation
  • Source of vitamin A (red palm oil)
  • Vitamin E (tocotrienols)
  • Skin and hair care
  • General nutrition

Palm oil is a widely used edible oil pressed from the fruit of the oil palm tree, and red palm oil is a notable source of vitamin A and vitamin E compounds called tocotrienols. As a food it is generally considered safe, but it is high in saturated fat, so it should be used in moderation as part of a balanced diet. Talk with your pharmacist or doctor before using concentrated palm-oil supplements, especially if you have heart or cholesterol concerns.

Elaeis guineensis · Arecaceae · Fruit and seed (kernel) · Cooking oil, capsules, red palm oil, tocotrienol/tocopherol supplements

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

Palm Oil: dosing

There is no official standardized dose of palm oil as a supplement. As a cooking oil, it is simply used in normal food amounts, ideally in moderation because of its saturated fat.For supplements such as red palm oil or tocotrienol products, the right amount varies by product and the reason for use.

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

Read the full Palm Oil monograph & all interactions
Medication

About Letrozole

What Is Letrozole Used For?

Brand name: Femara

Letrozole (brand name Femara) is used to treat breast cancer in postmenopausal women whose tumors are driven by estrogen. It is used in three settings: as adjuvant (after-surgery) treatment for hormone receptor positive early breast cancer; as extended adjuvant treatment for women who have already completed about five years of tamoxifen therapy; and as first- or second-line treatment for locally advanced or metastatic (spread) breast cancer.

Femara is specifically indicated for first-line treatment of hormone receptor positive or receptor-unknown locally advanced or metastatic breast cancer, and for advanced breast cancer in women whose disease has progressed after antiestrogen therapy.

See full Letrozole drug information
Keep checking

Other Drugs & Palm Oil

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

0Major
122Moderate
0Minor
2,707No known interaction
122 Moderate 2,707 No interaction
Moderate

122 interactions

Showing 60 of 122 moderate interactions — see all 122 on the Palm Oil page.

No interaction 2,707 drugs checked — show the list

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

Showing the 60 most looked-up of 2,707 medications checked with no known interaction — see the full Palm Oil list.

See the full Palm Oil interactions page
See every supplement checked against Letrozole, ranked by severity
Evidence & sources

Palm Oil References

The 12 references that drive our Palm Oil 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. Radhika MS, Bhaskaram P, Balakrishna N, Ramalakshmi BA. Red palm oil supplementation: a feasible diet-based approach to improve vitamin A status of pregnant women and their infants. Food Nutr Bull 2003;24:208-17.
  2. Zagre NM, Delpeuch F, Traissac P, Delisle H. Red palm oil as a source of vitamin A for mothers and children: impact of a pilot project in Burkina Faso. Public Health Nutr 2003;6:733-42. PubMed
  3. Lietz G, Henry CJ, Mulokozi G, et al. Comparison of the effects of supplemental red palm oil and sunflower oil on maternal vitamin A status. Am J Clin Nutr 2001;74:501-9. PubMed
  4. Sanchez-Muniz FJ, Oubina P, Rodenas S, et al. Platelet aggregation, thromboxane production and thrombogenic ratio in postmenopausal women consuming high oleic acid-sunflower oil or palmolein. Eur J Nutr 2003:42:299-306. PubMed
  5. Vega-Lopez, S., Ausman, L. M., Jalbert, S. M., Erkkila, A. T., and Lichtenstein, A. H. Palm and partially hydrogenated soybean oils adversely alter lipoprotein profiles compared with soybean and canola oils in moderately hyperlipidemic subjects. Am J Cli
  6. Cater, N. B., Heller, H. J., and Denke, M. A. Comparison of the effects of medium-chain triacylglycerols, palm oil, and high oleic acid sunflower oil on plasma triacylglycerol fatty acids and lipid and lipoprotein concentrations in humans. Am.J Clin.Nutr PubMed
  7. Fattore E, Bosetti C, Brighenti F, et al. Palm oil and blood lipid-related markers of cardiovascular disease: a systematic review and meta-analysis of dietary intervention trials. Am J Clin Nutr 2014;99:1331-50. PubMed
  8. Sun Y, Neelakantan N, Wu Y, et al. Palm oil consumption increases LDL cholesterol compared with vegetable oils low in saturated fat in a meta-analysis of clinical trials. J Nutr 2015;145:1549-58. PubMed
  9. Chen BK, Seligman B, Farquhar JW, Goldhaber-Fiebert JD. Multi-Country analysis of palm oil consumption and cardiovascular disease mortality for countries at different stages of economic development: 1980-1997. Global Health 2011;7:45. PubMed
  10. Voon PT, Lee ST, Ng TKW, et al. Intake of palm olein and lipid status in healthy adults: a meta-analysis. Adv Nutr 2019;10(4):647-59. PubMed
  11. Wang F, Zhao D, Yang Y, Zhang L. Effect of palm oil consumption on plasma lipid concentrations related to cardiovascular disease: a systematic review and meta-analysis. Asia Pac J Clin Nutr 2019;28(3):495-506.
  12. Hisham MDB, Aziz Z, Huin WK, Teoh CH, Jamil AHA. The effects of palm oil on serum lipid profiles: A systematic review and meta-analysis. Asia Pac J Clin Nutr 2020;29(3):523-536.

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 Palm Oil and Letrozole Together: Common Questions

Is it safe to take Palm Oil with Letrozole?
We do not list a known interaction between Palm Oil and Letrozole. 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.
How was the Palm Oil and Letrozole combination checked?
Interactions in our licensed database are recorded against drug classes. Letrozole is filed under 4 classifications, and Palm Oil has documented interactions with 1 drug class — none of Letrozole'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 Palm Oil interact with any other medications?
Yes. Palm Oil has 122 documented drug interactions in our database — Letrozole 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 Letrozole interact with any supplements?
Yes. Letrozole has documented interactions with 142 supplements in our database — Palm Oil is not one of them. The Letrozole interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Palm Oil monograph Uses, safety profile, and every drug interaction in one place Letrozole drug information The full plain-English guide to this medication Letrozole supplement interactions Every supplement checked against Letrozole, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 12 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Letrozole and Palm Oil?

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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.