Drug & supplement interaction

Calcium D-glucarate + Letrozole

Letrozole brand name: Femara.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Calcium D-glucarate 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

Calcium D-glucarate 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 Calcium D-glucarate 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.

Calcium D-glucarate safety at a glance

Calcium D-glucarat... overall Use caution It appears generally well tolerated in small studies, but long-term safety in humans is not well established.
Pregnancy Avoid There is not enough safety information, so it is best avoided during pregnancy.
Breastfeeding Avoid Safety while breastfeeding is unknown, so it is best avoided.

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

Still wondering about combining Letrozole and Calcium D-glucarate? 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. Calcium D-glucarate has documented interactions with 3 drug classes — the most serious being alcohol (ethanol) (moderate), glucuronidated drugs (moderate) and kanamycin (minor) — 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

Calcium D-glucarate Does Interact With Other Medications

Calcium D-glucarate has 125 moderate, 1 minor known drug interactions in our database — Letrozole 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 Calcium D-glucarate

Covers the 2,830 medications we’ve checked against Calcium D-glucarate. 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 Calcium D-glucarate. 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 › Calcium D-glucarate’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Calcium D-glucarate side to compare — that is a limit of the record, not a statement that Calcium D-glucarate has no side effects.

Overlapping uses

What Letrozole Is Prescribed For, and What Calcium D-glucarate Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Letrozole is a prescription medicine with approved uses on its FDA label. Calcium D-glucarate is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Letrozole is prescribed for: 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.

Calcium D-glucarate has been studied for:

  • Breast cancer studied, not established Calcium D-glucarate has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Calcium D-glucarate for breast cancer

    Although there has been interest in using oral calcium D-glucarate for preventing breast cancer, there is insufficient reliable information about the clinical effects of calcium D-glucarate for this purpose.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Letrozole on your own; if you are taking Calcium D-glucarate for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Calcium D-glucarate 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 Calcium D-glucarate 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 Calcium D-glucarate 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 Calcium D-glucarate as Part of a Dietary Supplement Product? Check It for Interactions

We hold 369 real supplement products containing Calcium D-glucarate, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Calcium D-glucarate. Even though Calcium D-glucarate 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 Calcium D-glucarate 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 Calcium D-glucarate
Top half

#480 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 Calcium D-glucarate reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Calcium D-glucarate and Letrozole records this page draws on were last updated June 22, 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 Calcium D-glucarate

What is Calcium D-glucarate?

Calcium D-glucarate
  • Detoxification support
  • Hormone balance
  • Estrogen metabolism
  • Liver support
  • General wellness

Calcium D-glucarate is a supplement form of a natural compound found in fruits and vegetables that is promoted for 'detoxification' and helping the body clear excess hormones. Human evidence for these benefits is very limited, and most research comes from laboratory or animal studies. Talk to your pharmacist or doctor before using it, especially if you have a hormone-related condition.

Not applicable (a calcium salt of D-glucaric acid) · Tablets, capsules

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

Calcium D-glucarate: dosing

There is no official or standardized dose for calcium D-glucarate, and the best dose for any health goal has not been established in humans. Amounts used in supplements vary widely from product to product.The safest approach is to follow the directions on the product label and not exceed the recommended amount.

From our Calcium D-glucarate monograph — the full record covers uses, side effects and every documented interaction.

Read the full Calcium D-glucarate 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 & Calcium D-glucarate

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

0Major
125Moderate
1Minor
2,703No known interaction
Moderate

125 interactions

Showing 60 of 125 moderate interactions — see all 125 on the Calcium D-glucarate page.

Minor

1 interaction

No interaction 2,703 drugs checked — show the list
Evidence & sources

Calcium D-glucarate References

The 5 references that drive our Calcium D-glucarate 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. Dwivedi C, Heck WJ, Downie AA, et al. Effect of calcium glucarate on B-glucuronidase activity and glucarate content on certain vegetables and fruits. Biochem Med Metab Bio 1990;43:83-92.
  2. Furuno K, Matsubara S, Ando K, Suzuki S. Preventive effect of D-glucarate against renal damage induced by kanamycin. J Antibiot (Tokyo) 1976;29:950-3. PubMed
  3. Mezey E. Increased urinary excretion of D-glucarate acid in alcoholism. Res Commun Chem Pathol Pharmacol 1976;15:735-42.
  4. Pantuck EJ, Pantuck CB, Anderson KE, et al. Effect of brussels sprouts and cabbage on drug conjugation. Clin Pharmacol Ther 1984;35:161-9. PubMed
  5. Anon. Calcium-D-Glucarate. Altern Med Review 2002;7(4):336-9.

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 Calcium D-glucarate and Letrozole Together: Common Questions

Is it safe to take Calcium D-glucarate with Letrozole?
We do not list a known interaction between Calcium D-glucarate 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.
Are Calcium D-glucarate and Letrozole used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Calcium D-glucarate in each. That is a conversation for your prescriber, especially if Letrozole is being adjusted to a target.
How was the Calcium D-glucarate and Letrozole combination checked?
Interactions in our licensed database are recorded against drug classes. Letrozole is filed under 4 classifications, and Calcium D-glucarate has documented interactions with 3 drug classes — 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 Calcium D-glucarate interact with any other medications?
Yes. Calcium D-glucarate has 126 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 — Calcium D-glucarate 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

Still Have a Question About Letrozole and Calcium D-glucarate?

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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.