Interactions on record — worth a quick check against your medications. Based on 5 of 6 ingredients. Check your meds →
Dietary supplement

GI-BFF Ingredients & Drug Interactions

by Gaia Herbs Pro

GI-BFF label
See full label image
Capsule Category: 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 GI-BFF 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

GI-BFF is a dietary supplement by Gaia Herbs Pro with 6 active ingredients. Its ingredients are commonly taken for digestive upset and bloating, infant colic, menstrual cramps.Based on those ingredients, 1,244 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Chamomile Flower Supercritical Extract, Peppermint Leaf Essential Oil, Fennel. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against GI-BFF by Gaia Herbs Pro

Ask about any prescription or over-the-counter medication and we check it for interactions with GI-BFF by Gaia Herbs Pro — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of GI-BFF by Gaia Herbs Pro

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 11, 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 6 of its 6 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

GI-BFF contains six active ingredients chosen for digestive support. Fennel appears twice—once as the whole herb and once as a Bitter Fennel Seed extract—and has been studied for period pain (dysmenorrhea).

Peppermint Leaf Essential Oil is the most evidence-backed ingredient here, with established effectiveness for irritable bowel syndrome (IBS) and possible benefit for indigestion and nausea from chemotherapy. Cinnamon (Cassia variety) and German Chamomile Flower extract round out the formula; both have limited or insufficient evidence for their specific uses in GI health.

Benegut Perilla leaf extract completes the blend. The capsules also contain inactive ingredients: maltodextrin, pullulan (a plant-based capsule material), and acacia gum.

Does it work?

Strong evidence
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
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Supports occasional gas and bloating.
  • We looked for evidence on: Abdominal pain, Flatulence, Dyspepsia, Irritable bowel syndrome (IBS), Nausea and vomiting, Colic — and 4 related terms.
  • The strongest evidence on file: Peppermint is rated "Likely Effective" for Irritable bowel syndrome (IBS) (Natural Medicines).
  • Also on file: Peppermint is rated "Possibly Effective" for Chemotherapy-induced nausea and vomiting (CINV), Dyspepsia.
  • Also on file: Fennel is rated "Insufficient Reliable Evidence To Rate" for Constipation, Dyspepsia, Flatulence, Irritable bowel syndrome (IBS).

Peppermint leaf oil is the standout here—it's likely effective for irritable bowel syndrome and possibly effective for indigestion and nausea from chemotherapy. Fennel has possibly effective evidence for period pain but only insufficient evidence for the respiratory and other conditions it's traditionally used for.

Cinnamon, German chamomile, and Benegut Perilla all show insufficient reliable evidence for the conditions listed in our data, so we can't claim they work for any specific purpose in this product.

The evidence, ingredient by ingredient Fennel Cassia Cinnamon Perilla Peppermint German Chamomile

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 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most of these ingredients are generally well tolerated in food amounts or culinary doses. Fennel and cinnamon are safe as food seasonings but warrant caution in concentrated supplement form.

Fennel itself is rare but can trigger seizures, and both fennel and perilla carry allergic reaction risk—fennel cases have included breathing difficulty, and perilla has rare reports of anaphylaxis, especially from perilla seeds. Peppermint oil in high amounts or undiluted can cause chemical burns in the mouth and throat.

German chamomile may cause allergic reactions in people sensitive to ragweed plants. Common side effects are mild: gastrointestinal discomfort from fennel, abdominal pain and heartburn from peppermint, and dermatitis from topical chamomile exposure.

Cinnamon carries a theoretical risk of liver damage with very high long-term doses due to its coumarin content; one clinical trial reported a hypoglycemic seizure (low blood sugar event), though causation is unclear. Peppermint and cinnamon are rated likely safe in pregnancy and lactation, but fennel, perilla, and German chamomile should be avoided in medicinal amounts during pregnancy and lactation due to insufficient safety data.

Side effects, ingredient by ingredient Fennel Cassia Cinnamon Perilla Peppermint German Chamomile

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?
  • 4 of the 5 matched ingredients can interact with medications — Fennel, Peppermint, German Chamomile, Cassia Cinnamon.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications.
  • For scale: 1,245 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 you start GI-BFF, double-check these medication types: blood thinners and antiplatelet drugs (major bleeding risk from fennel), drugs broken down by your liver via CYP3A4, CYP2C9, CYP2C19, and CYP2D6 enzymes (levels may rise), hormone-based contraceptives and hormone replacement therapy (fennel and chamomile may reduce effectiveness), tamoxifen (fennel's estrogenic activity may interfere), ciprofloxacin/Cipro (fennel may cut its effectiveness by half), warfarin (documented case of increased bleeding with chamomile), and sedating drugs like sleep aids or antidepressants (peppermint and chamomile may add to drowsiness). No interactions are documented for Benegut Perilla leaf extract among the ingredients we could check.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

GI-BFF is most useful if you're dealing with IBS or mild indigestion—peppermint is the evidence-backed player here. It's a multi-ingredient blend, so medication interactions are a real concern: anyone on blood thinners, heart drugs, psychiatric medications, hormone therapy, or tamoxifen should check their specific drugs with our tool first.

Talk to your pharmacist before starting, especially if you're pregnant, breastfeeding, or have a ragweed allergy.

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

Assessment coverage: 6 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 23, 2025.

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 GI-BFF , straight from the product label.

Brand Gaia Herbs Pro
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Feb 23, 2025
DSLD ID 329506
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (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 GI-BFF by Gaia Herbs Pro, 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:
1 Capsule(s)
Servings per container
60
IngredientAmount% DV
Fennel100 mg--
Cinnamon85 mg--
Benegut Perilla leaf extract150 mg--
Peppermint Leaf Essential Oil40 mg--
Chamomile Flower Supercritical Extract25 mg--
Bitter Fennel Seed Supercritical Extract15 mg--

Other ingredients: Maltodextrin, Pullulan, Acacia Gum

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.
Formulation

Supports occasional gas & bloating

FDA Statement of Identity

Herbal Supplement

General Statements

Discover plant intelligence

Brand IP Statement(s)

Benegut is a registered trademark of Vital Solutions GmbH, Germany.

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

See for yourself

GI-BFF by Gaia Herbs Pro label

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

GI-BFF 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 GI-BFF by Gaia Herbs Pro

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Fennel

Interacts with
740 drugs
100 mg per serving

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some sm...

Fennel monograph & interactions

Cinnamon

Interacts with
442 drugs
85 mg per serving

Cassia cinnamon is the common, inexpensive cinnamon used in cooking, and it is also taken as a supplement, most often for blood sugar support. The evi...

Cinnamon monograph & interactions

Benegut Perilla leaf extract

No known
interactions
150 mg per serving

Perilla is an Asian mint-family plant used in cooking and traditional medicine, mainly for allergy, breathing, and digestive complaints. Most human ev...

Benegut Perilla leaf extract monograph & interactions

Peppermint Leaf Essential Oil

Interacts with
796 drugs
40 mg per serving

Peppermint is a popular herb with the best evidence supporting enteric-coated peppermint oil for easing IBS symptoms. It is generally well tolerated f...

Peppermint Leaf Essential Oil monograph & interactions

Chamomile Flower Supercritical Extract

Interacts with
960 drugs
25 mg per serving

German chamomile is a widely used herbal remedy taken mainly as a tea for calming, sleep, and digestive complaints. Early research suggests possible b...

Chamomile Flower Supercritical Extract monograph & interactions

Bitter Fennel Seed Supercritical Extract

Interacts with
740 drugs
15 mg per serving

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some sm...

Bitter Fennel Seed Supercritical Extract monograph & interactions

Other (inactive) ingredients: Maltodextrin, Pullulan, Acacia Gum. These complete the product’s ingredient list but are not active constituents.

Interaction report

GI-BFF by Gaia Herbs Pro Drug Interactions

Want to check YOUR meds against GI-BFF ?

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
1,244Drugs
1,231 Moderate 13 Minor

Ingredients driving the most interactions

Chamomile Flower Supercritical Extract 960
Peppermint Leaf Essential Oil 796
Fennel 740
Cinnamon 442

Individual Drug Interactions

The ingredients in GI-BFF interact with 1,244 drugs. Click any drug to see the details.

4 of the 6 ingredients in GI-BFF interact with drugs. Each result below shows which ingredient is responsible. Chamomile Flower Supercritical Extract Peppermint Leaf Essential Oil Fennel Cinnamon

Each ingredient & the kinds of drugs it affects

For each ingredient in GI-BFF with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Chamomile Flower Supercritical Extract9 drug types · 960 drugs

Cns Depressants

Theoretically, German chamomile might have additive effects when used with CNS depressants.
German chamomile has mild sedative effects. Theoretically, concomitant use with drugs with sedative properties can cause additive effects and side effects.

Likelihood Possible Evidence D
Contraceptive Drugs

Theoretically, large amounts of German chamomile might reduce the effectiveness of oral contraceptives.
In vitro, German chamomile has demonstrated antiestrogenic activity. Theoretically, concomitant use of large amounts of German chamomile might interfere with contraceptive drugs through competition for estrogen receptors.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, German chamomile might inhibit CYP2C9 and increase levels of drugs metabolized by these enzymes.
In vitro evidence shows that German chamomile might inhibit CYP2C9. So far, this interaction has not been reported in humans. However, there might be an increase in the levels of drugs metabolized by CYP2C9 in patients taking German chamomile.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, German chamomile might inhibit CYP2D6 and increase levels of drugs metabolized by these enzymes.
In vitro evidence shows that German chamomile might inhibit CYP2D6. So far, this interaction has not been reported in humans. However, there might be an increase in the levels of drugs metabolized by CYP2D6 in patients taking German chamomile.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, German chamomile might inhibit CYP3A4 and increase levels of drugs metabolized by these enzymes.
In vitro evidence shows that German chamomile might inhibit CYP3A4. So far, this interaction has not been reported in humans. However, there might be an increase in the levels of drugs metabolized by CYP3A4 in patients taking German chamomile.

Likelihood Possible Evidence D
Estrogens

Theoretically, large amounts of German chamomile might reduce the effectiveness of estrogens.
In vitro, German chamomile has demonstrated antiestrogenic activity. Theoretically, large amounts of German chamomile might interfere with hormone replacement therapy through competition for estrogen receptors.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, large amounts of German chamomile might interfere with the activity of tamoxifen.
In vitro, German chamomile has demonstrated antiestrogenic activity.

Likelihood Possible Evidence D
Warfarin (Coumadin)

German chamomile might increase the effects of warfarin and increase the risk of bleeding.
In one case, a 70-year-old female taking warfarin developed retroperitoneal hematoma and bilateral recti muscle bleeding along with an INR of 7.9 following ingestion of German chamomile tea 4-5 cups daily and use of a topical chamomile-based lotion applied 4-5 times daily.

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

Theoretically, German chamomile might inhibit CYP1A2 and increase levels of drugs metabolized by these enzymes.
In vitro and animal research shows that German chamomile might inhibit CYP1A2. So far, this interaction has not been reported in humans. However, there might be an increase in the levels of drugs metabolized by CYP1A2 in patients taking German chamomile.

Likelihood Possible Evidence D
Chamomile Flower Supercritical Extract full monograph & interactions

Peppermint Leaf Essential Oil5 drug types · 796 drugs

Cyclosporine (Neoral, Sandimmune)

Theoretically, peppermint oil might increase the levels and adverse effects of cyclosporine.
In animal research, peppermint oil inhibits cyclosporine metabolism and increases cyclosporine levels. Inhibition of cytochrome P450 3A4 (CYP3A4) may be partially responsible for this interaction. An interaction between peppermint oil and cyclosporine has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, peppermint might increase the levels of CYP2C19 substrates.
In vitro research shows that peppermint oil inhibits CYP2C19. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, peppermint might increase the levels of CYP2C9 substrates.
In vitro research shows that peppermint oil inhibits CYP2C9. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, peppermint might increase the levels of CYP3A4 substrates.
Clinical research in healthy volunteers shows that a single dose of peppermint oil 600 mg inhibits CYP3A4 enzymes and increases the AUC of felodipine, a CYP3A4 substrate. However, in vitro research suggests that peppermint oil only inhibits CYP3A4 at very high concentrations.

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

Theoretically, peppermint might increase the levels of CYP1A2 substrates.
In vitro and animal research shows that peppermint oil and peppermint leaf inhibit CYP1A2. However, in clinical research, peppermint tea did not significantly affect the metabolism of caffeine, a CYP1A2 substrate. It is possible that the 6-day duration of treatment may have been too short to identify a difference.

Likelihood Possible Evidence B
Peppermint Leaf Essential Oil full monograph & interactions

Fennel6 drug types · 740 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, fennel might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.

Animal research suggests that fennel oil has antithrombotic and antiplatelet effects.

Likelihood Possible Evidence D
Ciprofloxacin (Cipro)

Theoretically, fennel might decrease the levels and clinical effects of ciprofloxacin.

Animal research shows that fennel reduces ciprofloxacin bioavailability by nearly 50%, possibly due to the metal cations such as calcium, iron, and magnesium contained in fennel. This study also found that fennel increased tissue distribution and slowed elimination of ciprofloxacin.

Likelihood Probable Evidence D
Contraceptive Drugs

Theoretically, taking large amounts of fennel might decrease the effects of contraceptive drugs due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, fennel might increase levels of drugs metabolized by CYP3A4.

In vitro research suggests that fennel inhibits CYP3A4 enzyme activity. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, taking large amounts of fennel might interfere with hormone replacement therapy due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, taking large amounts of fennel might decrease the antiestrogenic effect of tamoxifen.

Some constituents of fennel have estrogenic activity, which may interfere with the antiestrogenic activity of tamoxifen.

Likelihood Possible Evidence D
Fennel full monograph & interactions

Cinnamon2 drug types · 442 drugs

Antidiabetes Drugs

Theoretically, cassia cinnamon may have additive effects with antidiabetes drugs.
Cassia cinnamon may lower blood glucose levels, and have additive effects in patients treated with antidiabetic agents. Dose adjustments to diabetes medications might be necessary.

Likelihood Possible Evidence B
Hepatotoxic Drugs

Theoretically, large doses of cassia cinnamon might cause additive effects when used with hepatotoxic drugs.
There is some concern that ingesting large amounts of cassia cinnamon for an extended duration might cause hepatotoxicity in some people. Cassia cinnamon contains coumarin, which can cause hepatotoxicity in animal models. In humans, very high doses of coumarin from 50-7000 mg/day can result in hepatotoxicity that resolves when coumarin use is discontinued. Lower amounts might also cause liver problems in sensitive people, such as those with liver disease or those taking potentially hepatotoxic agents.

Likelihood Possible Evidence D
Cinnamon full monograph & interactions
The maker

Brand information

Manufacturer and brand details for GI-BFF , from the product label.

Gaia Herbs Pro

See all Gaia Herbs Pro products
Name
GAIA HERBS, INC.
Street Address
101 Gaia Herbs Dr.
City
Brevard
State
NC
ZipCode
28712
Pharmacist Counseling Corner

GI-BFF by Gaia Herbs Pro: Common Questions

Does GI-BFF by Gaia Herbs Pro interact with any medications?
Yes. Based on its ingredients, GI-BFF has a known interaction with 1,244 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
GI-BFF contains 6 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is 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.
Is GI-BFF safe to take if I'm pregnant or breastfeeding?
Not in medicinal amounts. Fennel, Perilla, and German Chamomile should be avoided during pregnancy and lactation due to limited safety data—the facts advise against medicinal doses. Peppermint and Cinnamon are rated likely safe. Talk with your doctor or pharmacist about whether this product makes sense for you personally.
Can I take this if I'm on birth control pills?
You need to check with your pharmacist first. Fennel and German Chamomile both contain compounds with estrogenic activity that may theoretically reduce how well contraceptive pills work, especially at higher doses. It's a Moderate-severity concern worth confirming before you start.
What is peppermint oil actually for in this blend?
Peppermint is the most proven ingredient here—it's likely effective for irritable bowel syndrome and possibly effective for indigestion and nausea from chemotherapy. It's the primary reason you might consider this product.
Can fennel really cause seizures?
Seizures are a rare serious side effect reported with fennel use. Much more common are mild gastrointestinal upset, photosensitivity (sun sensitivity), and allergic reactions in people who are sensitive to fennel. If you have a history of seizures, mention this product to your doctor or pharmacist first.
Will this help with my anxiety?
The evidence doesn't support it. German Chamomile has been studied for anxiety, but our data shows insufficient evidence to say it works. Peppermint and Fennel haven't shown reliable evidence for anxiety either, so this isn't the right product if that's your main concern.
Is there anything in this product besides the active ingredients?
Yes—the capsules contain three inactive ingredients: maltodextrin, pullulan (the capsule material itself), and acacia gum as a binder. These are standard fillers that help hold the supplement together.

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

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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.

GI-BFF label
Go deeper

The Full Monographs Behind GI-BFF ’s Ingredients

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

Herb & supplement monograph

Fennel

Interacts with 740 drugs

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some small studies suggest possible benefit for...

Read the full Fennel monograph → Herb & supplement monograph

Cassia Cinnamon

Interacts with 442 drugs

Cassia cinnamon is the common, inexpensive cinnamon used in cooking, and it is also taken as a supplement, most often for blood sugar support. The evidence for its health benefits is mixed a...

Read the full Cassia Cinnamon monograph → Herb & supplement monograph

Perilla

Perilla is an Asian mint-family plant used in cooking and traditional medicine, mainly for allergy, breathing, and digestive complaints. Most human evidence is limited or preliminary, so it...

Read the full Perilla monograph → Herb & supplement monograph

Peppermint

Interacts with 796 drugs

Peppermint is a popular herb with the best evidence supporting enteric-coated peppermint oil for easing IBS symptoms. It is generally well tolerated for most adults, but it can cause heartbu...

Read the full Peppermint monograph → Herb & supplement monograph

German Chamomile

Interacts with 960 drugs

German chamomile is a widely used herbal remedy taken mainly as a tea for calming, sleep, and digestive complaints. Early research suggests possible benefits for mild anxiety and some skin o...

Read the full German Chamomile monograph →
Sources

Sources & How We Checked

GI-BFF '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 97 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.

Fennel 17 references
  1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Zhu M, Wong PY, Li RC. Effect of oral administration of fennel (Foeniculum vulgare) on ciprofloxacin absorption and disposition in the rat. J Pharm Pharmacol 1999;51:1391-6.
  4. Gral N, Beani JC, Bonnot D, et al. [Plasma levels of psoralens after celery ingestion]. Ann Dermatol Venereol 1993;120:599-603.
  5. Burkhard PR, Burkhardt K, Haenggeli CA, Landis T. Plant-induced seizures: reappearance of an old problem. J Neurol 1999;246:667-70. PubMed
  6. Rosti L, Nardini A, Bettinelli ME, Rosti D. Toxic effects of a herbal tea mixture in two newborns. Acta Paediatrica 1994;83:683. PubMed
  7. Cuzzolin L, Zaffani S, and Benoni G. Safety implications regarding use of phytomedicines. Eur.J Clin Pharmacol. 2006;62:37-42. PubMed
  8. Tognolini, M., Ballabeni, V., Bertoni, S., Bruni, R., Impicciatore, M., and Barocelli, E. Protective effect of Foeniculum vulgare essential oil and anethole in an experimental model of thrombosis. Pharmacol.Res 2007;56(3):254-260. PubMed
  9. Subehan, Usia, T., Iwata, H., Kadota, S., and Tezuka, Y. Mechanism-based inhibition of CYP3A4 and CYP2D6 by Indonesian medicinal plants. J Ethnopharmacol. 5-24-2006;105(3):449-455. PubMed
  10. Tognolini, M., Barocelli, E., Ballabeni, V., Bruni, R., Bianchi, A., Chiavarini, M., and Impicciatore, M. Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. Life Sci. 2-23-2006;78(13):1419-1432. PubMed
  11. Subehan, Zaidi, S. F., Kadota, S., and Tezuka, Y. Inhibition on human liver cytochrome P450 3A4 by constituents of fennel (Foeniculum vulgare): identification and characterization of a mechanism-based inactivator. J Agric.Food Chem. 12-12-2007;55(25):101 PubMed
  12. LEVY, S. B. Bronchial asthma due to ingestion of fennel and fennel seed. Ann.Allergy 1948;6(4):415.
  13. Ottolenghi, A., De Chiara, A., Arrigoni, S., Terracciano, L., and De Amici, M. [Diagnosis of food allergy caused by fruit and vegetables in children with atopic dermatitis]. Pediatr Med Chir 1995;17(6):525-530.
  14. Trabace L, Tucci P, Ciuffreda L, et al. "Natural" relief of pregnancy-related symptoms and neonatal outcomes: above all do no harm. J Ethnopharmacol. 2015;174:396-402. PubMed
  15. Denaxa D, Arkwright PD. Fennel as a cause of immediate hypersensitivity to toothpaste. Ann Allergy Asthma Immunol. 2020;125(1):99-100. PubMed
  16. Lee HW, Ang L, Lee MS, Alimoradi Z, Kim E. Fennel for reducing pain in primary dysmenorrhea: a systematic review and meta-analysis of randomized controlled trials. Nutrients 2020;12(11):3438. PubMed
  17. Mathew T, John SK, Javali M, Vasireddy M, Nadig R, Sarma GRK. Substance use related cluster headache: A case series. Headache 2022;62(7):908-910. PubMed

See these in context on the Fennel monograph →

Cassia Cinnamon 20 references
  1. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
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Perilla 4 references
  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Kanzaki, T. and Kimura, S. Occupational allergic contact dermatitis from Perilla frutescens (shiso). Contact Dermatitis 1992;26(1):55-56.
  3. Yu H, Qiu JF, Ma LJ, Hu YJ, Li P, Wan JB. Phytochemical and phytopharmacological review of Perilla frutescens L. (Labiatae), a traditional edible-medicinal herb in China. Food Chem Toxicol 2017;108(Pt B):375-91. PubMed
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Peppermint 41 references
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  27. Tran, A., Pratt, M., and DeKoven, J. Acute allergic contact dermatitis of the lips from peppermint oil in a lip balm. Dermatitis 2010;21(2):111-115. DOI
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German Chamomile 15 references
  1. Subiza J, Subiza JL, Hinojosa M, et al. Anaphylactic reaction after the ingestion of chamomile tea; a study of cross-reactivity with other composite pollens. J Allergy Clin Immunol 1989;84:353-8. PubMed
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