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Dietary supplement

E I-3-C (Indole-3-Carbinol) Ingredients & Drug Interactions

by AFI America's Finest

E I-3-C (Indole-3-Carbinol) label
See full label image
Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking E I-3-C (Indole-3-Carbinol) against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

E I-3-C (Indole-3-Carbinol) is a dietary supplement by AFI America's Finest with 1 active ingredient. Its ingredients are commonly taken for estrogen and hormone balance support, breast and cervical health, prostate health.Based on those ingredients, 294 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Indole-3-Carbinol. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against E I-3-C (Indole-3-Carbinol) by AFI America's Finest

Ask about any prescription or over-the-counter medication and we check it for interactions with E I-3-C (Indole-3-Carbinol) by AFI America's Finest — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of E I-3-C (Indole-3-Carbinol) by AFI America's Finest

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 23, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: indole-3-carbinol, a compound derived from cruciferous vegetables like broccoli and cabbage. The capsule also contains inactive ingredients (dicalcium phosphate, cellulose, magnesium stearate, and silica) that serve as fillers and binders.

Does it work?

Not established
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use — see Indole-3-carbinol's own graded uses on its monograph.

Why this rating?
  • The label markets this product for: supports woman's health.
  • We looked for evidence on: Breast cancer, Cervical dysplasia, Ovarian cancer, Hormone balance, Estrogen metabolism.
  • The closest evidence on file: Indole-3-carbinol is rated "Insufficient Reliable Evidence To Rate" for Breast cancer (Natural Medicines).
  • Also on file: Indole-3-carbinol is rated "Insufficient Reliable Evidence To Rate" for Cervical dysplasia, Ovarian cancer.

The evidence for indole-3-carbinol in treating breast cancer, colorectal cancer, cervical dysplasia, liver disease, or fibromyalgia is insufficient to rate it as effective. We don't have reliable clinical data to say whether this supplement works for these purposes.

The evidence, ingredient by ingredient Indole-3-carbinol

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Indole-3-carbinol appears generally well tolerated when taken orally, but the most common side effects include diarrhea, nausea, rash, tremor, and unsteadiness. Higher doses have been linked to imbalance and tremor — one adult taking 400 mg twice daily developed these symptoms within 10 days, which resolved when the dose was halved.

Indole-3-carbinol from food is likely fine, but supplement doses are less studied and should be used cautiously. Safety data during pregnancy is not on file — talk with your doctor before using it if you're pregnant.

Concentrated supplements should be avoided during breastfeeding due to insufficient safety data and possible hormone effects.

Side effects, ingredient by ingredient Indole-3-carbinol

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Indole-3-carbinol.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs.
  • For scale: 294 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, check with your doctor or pharmacist if you take blood thinners or antiplatelet drugs (like warfarin, apixaban, or aspirin) — indole-3-carbinol may increase bleeding risk. Also flag any estrogen-based hormonal medications, including birth control and hormone replacement therapy.

If you take medications metabolized by the CYP1A2 enzyme, your doctor should know you're considering this supplement, since it may reduce their effectiveness.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

This supplement may appeal to you if you're interested in plant-based compounds, but the effectiveness for common health goals isn't well established. You should be careful if you take blood thinners, hormonal birth control, hormone replacement therapy, or medications metabolized by your liver — all warrant a conversation with your doctor or pharmacist first.

If you're pregnant or breastfeeding, check with your healthcare provider before starting it.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Dec 23, 2011.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about E I-3-C (Indole-3-Carbinol), straight from the product label.

Brand AFI America's Finest
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Dec 23, 2011
DSLD ID 3665
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses Structure/Function
Intended target group(s) Adult Female (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for E I-3-C (Indole-3-Carbinol) by AFI America's Finest, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
3 Capsule(s)
IngredientAmount% DV
Indole-3-Carbinol100 mg--

Other ingredients: Dicalcium Phosphate, Cellulose, Magnesium Stearate, Silica

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Suggested Use: Take one to three capsules daily with water or as directed by a health care professional.

FDA Disclaimer Statement

*These statements have not been evaluated by the F.D.A. This product is not intended to diagnose treat, cure or prevent any disease

General Statements

***A Registered trademark of Sabinsa Corporation

Formula

Supports Woman's Health*

Brand IP Statement(s)

Science of Life for the Joy of Living(TM)

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

E I-3-C (Indole-3-Carbinol) by AFI America's Finest label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

E I-3-C (Indole-3-Carbinol) label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in E I-3-C (Indole-3-Carbinol) by AFI America's Finest

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Amounts shown are per serving.

Indole-3-Carbinol

Interacts with
294 drugs
100 mg per serving

Indole-3-carbinol (I3C) is a compound formed when you eat cruciferous vegetables like broccoli and cabbage, and it is sold as a supplement mainly for...

Indole-3-Carbinol monograph & interactions

Other (inactive) ingredients: Dicalcium Phosphate, Cellulose, Magnesium Stearate, Silica. These complete the product’s ingredient list but are not active constituents.

Interaction report

E I-3-C (Indole-3-Carbinol) by AFI America's Finest Drug Interactions

Want to check YOUR meds against E I-3-C (Indole-3-Carbinol)?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
294Drugs
294 Moderate

Ingredients driving the most interactions

Indole-3-Carbinol 294

Individual Drug Interactions

The ingredients in E I-3-C (Indole-3-Carbinol) interact with 294 drugs. Click any drug to see the details.

1 of the 1 ingredient in E I-3-C (Indole-3-Carbinol) interact with drugs. Each result below shows which ingredient is responsible. Indole-3-Carbinol

Each ingredient & the kinds of drugs it affects

For each ingredient in E I-3-C (Indole-3-Carbinol) with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Indole-3-Carbinol3 drug types · 294 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, indole-3-carbinol might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.
In vitro research shows that indole-3-carbinol inhibits platelet aggregation.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, indole-3-carbinol might increase the metabolism of CYP1A2 substrates and lower serum concentrations.
Animal research shows that indole-3-carbinol induces CYP1A2 enzymes.

Likelihood Possible Evidence D
Estrogens

Indole-3-carbinol might interfere with the effects of estrogen therapy.
Preliminary clinical and in vitro evidence shows that indole-3-carbinol has antiestrogenic activity.

Likelihood Possible Evidence D
Indole-3-Carbinol full monograph & interactions
The maker

Brand information

Manufacturer and brand details for E I-3-C (Indole-3-Carbinol), from the product label.

AFI America's Finest

See all AFI America's Finest products
Name
America's Finest
Pharmacist Counseling Corner

E I-3-C (Indole-3-Carbinol) by AFI America's Finest: Common Questions

Does E I-3-C (Indole-3-Carbinol) by AFI America's Finest interact with any medications?
Yes. Based on its ingredients, E I-3-C (Indole-3-Carbinol) has a known interaction with 294 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
E I-3-C (Indole-3-Carbinol) contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Will this interact with my birth control?
Yes — indole-3-carbinol may interfere with how estrogen-based hormonal contraceptives work by reducing their effect in your body. Talk with your doctor before combining this supplement with any hormonal birth control.
What are the most common side effects?
Diarrhea, nausea, rash, tremor, and unsteadiness. At higher doses, unsteadiness and imbalance are more likely — one person taking 400 mg twice daily developed these symptoms after 10 days, which improved when the dose was cut in half.
Is it safe to take if I'm pregnant?
There isn't enough safety data to know either way. Talk with your doctor or pharmacist about whether it's right for you during pregnancy.
Can I take this while breastfeeding?
No — safety hasn't been established while breastfeeding, and indole-3-carbinol has possible hormone effects. Your healthcare provider can advise you on whether to use it.
Does it actually work for cancer prevention or fibromyalgia?
We don't have reliable clinical evidence to say whether indole-3-carbinol is effective for breast cancer, colorectal cancer, cervical dysplasia, liver disease, or fibromyalgia. More research is needed.

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

Not sure if E I-3-C (Indole-3-Carbinol) is safe with your meds?

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

E I-3-C (Indole-3-Carbinol) label
Go deeper

The Full Monographs Behind E I-3-C (Indole-3-Carbinol)’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Indole-3-carbinol

Interacts with 294 drugs

Indole-3-carbinol (I3C) is a compound formed when you eat cruciferous vegetables like broccoli and cabbage, and it is sold as a supplement mainly for hormone-related and cell-protective effe...

Read the full Indole-3-carbinol monograph →
Sources

Sources & How We Checked

E I-3-C (Indole-3-Carbinol)'s label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 9 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Indole-3-carbinol 9 references
  1. Rosen CA, Woodson GE, Thompson JW, et al. Preliminary results of the use of indole-3-carbinol for recurrent respiratory papillomatosis. Otolaryngol Head Neck Surg 1998;118:810-5. PubMed
  2. Bell MC, Crowley-Nowick P, Bradlow HL, et al. Placebo-controlled trial of indole-3-carbinol in the treatment of CIN. Gynecol Oncol 2000;78:123-9. PubMed
  3. He YH, Friesen MD, Ruch RJ, Schut HA. Indole-3-carbinol as a chemopreventive agent in 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) carcinogenesis: inhibition of PhIP-DNA adduct formation, acceleration of PhIP metabolism, and induction of cytoch
  4. Kim, Y. S. and Milner, J. A. Targets for indole-3-carbinol in cancer prevention. J.Nutr.Biochem. 2005;16(2):65-73. PubMed
  5. Anon. Indole-3-carbinol. Monograph. Alternative Medicine Review 2005;10(4):337-42.
  6. McAlindon TE, Gulin J, Chen T, et al. Indole-3-carbinol in women with SLE: effect on estrogen metabolism and disease activity. Lupus 2001;10:779-83. PubMed
  7. Reed GA, Peterson KS, Smith HJ, et al. A phase I study of indole-3-carbinol in women: tolerability and effects. Cancer Epidemiol Biomarkers Prev 2005;14:1953-60. PubMed
  8. Bradlow HL, Michnovicz JJ, Halper M, et al. Long-term responses of women to indole-3-carbinol or a high fiber diet. Cancer Epidemiol Biomarkers Prev 1994;3:591-5.
  9. Paliwal P, Chauhan G, Gautam D, Dash D, Patne SCU, Krishnamurthy S. Indole-3-carbinol improves neurobehavioral symptoms in a cerebral ischemic stroke model. Naunyn Schmiedebergs Arch Pharmacol. 2018;391(6):613-625. PubMed

See these in context on the Indole-3-carbinol monograph →

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

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