Interactions on record — worth a quick check against your medications. Based on 7 of 12 ingredients. Check your meds →
Dietary supplement

GI-Zyme Ingredients & Drug Interactions

by Mannatech

GI-Zyme label
See full label image
Capsule Category: Botanical With Nutrients
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-Zyme 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-Zyme is a dietary supplement by Mannatech with 12 active ingredients. Its ingredients are commonly taken for digestive upset and bloating, infant colic, menstrual cramps.Based on those ingredients, 1,150 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Ginger, Beet Fiber, Peppermint. 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-Zyme by Mannatech

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

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HelloPharmacist Scorecard of GI-Zyme by Mannatech

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 30, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 1 of its 12 active ingredients.
  • “Proprietary Herbal Blend” is a proprietary blend — the label gives one combined amount (150 mg) without saying how much of each component you get.
  • “Proprietary Phase 1 Enzyme Blend” is a proprietary blend — the label gives one combined amount (96 mg) without saying how much of each component you get.
  • “Proprietary Phase 2 Enzyme Blend” is a proprietary blend — the label gives one combined amount (70 mg) without saying how much of each component you get.

GI-Zyme contains 12 ingredients, with 6 active digestive enzymes and additional botanicals. The enzyme blend includes protease (breaks down protein), lipase (breaks down fat), amylase (breaks down starch), cellulase, peptidase, invertase, alpha-galactosidase, and lactase (helps with milk sugar digestion).

The product also contains fennel, ginger, and peppermint as botanicals, plus beet fiber. Vegetable cellulose is the only inactive ingredient listed.

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: improve digestion and nutrient absorption.
  • We looked for evidence on: Abdominal pain, Colic, Dyspepsia, Flatulence, Irritable bowel syndrome (IBS), Lactose intolerance — and 4 related terms.
  • The strongest evidence on file: Lactase is rated "Effective" for Lactose intolerance (Natural Medicines).
  • Also on file: Peppermint is rated "Likely Effective" for Irritable bowel syndrome (IBS).
  • Also on file: Beet is rated "Possibly Effective" for Exercise-induced muscle soreness.

Lactase in this product is effective for lactose intolerance. Peppermint is likely effective for irritable bowel syndrome (IBS) and possibly effective for indigestion (dyspepsia).

Ginger is possibly effective for pregnancy-related nausea, period pain (dysmenorrhea), and osteoarthritis. Fennel is possibly effective for period pain.

Beet fiber is possibly effective for athletic performance and exercise-related muscle soreness. For the other active enzymes and several herbal uses listed, the evidence we hold is insufficient to establish effectiveness, or they show no significant benefit.

The evidence, ingredient by ingredient Fennel Ginger Peppermint Proteolytic Enzymes (proteases) Lactase Lipase Beet

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 7 of the 7 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 7 of 7.
  • General safety write-ups exist for 7 of 7.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Protease, lipase, and lactase are generally well tolerated in adults, though digestive upset can occur. Lactase is likely safe in pregnancy and is generally well tolerated while breastfeeding.

Ginger is likely safe in pregnancy at typical doses and likely safe while breastfeeding. Fennel and peppermint should be avoided in concentrated amounts during pregnancy due to limited safety data—fennel has estrogenic properties that raised concern, and peppermint oil is understudied in this setting.

Peppermint and peppermint oil are likely safe while breastfeeding, but concentrated supplements warrant medical advice. Beet is generally well tolerated as food; concentrated supplements lack sufficient pregnancy and breastfeeding data.

Common side effects include digestive discomfort (abdominal pain, diarrhea, heartburn, burping), and rare reports include allergic reactions to protease or fennel. Ginger at higher doses (5 grams per day or more) increases the risk of side effects.

Red or black stools may occur with beet.

Side effects, ingredient by ingredient Fennel Ginger Peppermint Proteolytic Enzymes (proteases) Lactase Lipase Beet

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 7 matched ingredients can interact with medications — Beet, Fennel, Peppermint, Ginger.
  • 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: 1,151 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 GI-Zyme, check with your doctor or pharmacist if you take tamoxifen (breast cancer medication), blood thinners or antiplatelet drugs (like warfarin, aspirin, or clopidogrel), diabetes medications, hormonal contraceptives or hormone replacement therapy, blood pressure medications, or medications that rely on liver enzymes for processing. Fennel, ginger, peppermint, and beet fiber each affect how your body handles certain drugs, and the combined effect of multiple ingredients warrants a review of your specific prescriptions.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

GI-Zyme is designed to support digestion through enzyme and herbal ingredients with some evidence for lactose intolerance, IBS, indigestion, and nausea. If you take blood thinners, diabetes medications, hormone therapy, cancer medications, or drugs processed by the liver, you'll want to check this product's ingredients against your prescriptions before starting.

Talk with your doctor or pharmacist to make sure GI-Zyme won't interfere with your medications or health conditions.

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

Assessment coverage: 7 of 12 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 25, 2014.

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-Zyme, straight from the product label.

Brand Mannatech
Net contents 90 Capsule(s)
Market status On market
Date entered into DSLD Jun 25, 2014
DSLD ID 34835
Product type Botanical With Nutrients
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-Zyme by Mannatech, 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)
IngredientAmount% DV
Amylase0 NP--
Protease0 NP--
Lipase0 NP--
Lactase0 NP--
Cellulase0 NP--
Peptidase0 NP--
Fennel0 NP--
Ginger0 NP--
Invertase0 NP--
Peppermint0 NP--
Alpha-Galactosidase0 NP--
Proprietary Herbal Blend150 mg--
Proprietary Phase 1 Enzyme Blend96 mg--
Proprietary Phase 2 Enzyme Blend70 mg--
Beet Fiber44 mg--

Other ingredients: Vegetable Cellulose

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.
General Statements

GI-ZYME

GI-Zyme capsules can help improve the level of digestion and may help ensure maximum levels of nutrient absorption.*

DIGESTIVE ENZYME

SUPPORTS DIGESTIVE ABSORPTION*

Suggested/Recommended/Usage/Directions

Recommended Adult Use: Take one capsule before each meal.

Precautions

WARNING: If you are pregnant, nursing, taking medication, have a health condition, or are planning a medical procedure, consult your health professional before use.

Discontinue use and consult your doctor if any adverse reactions occur.

Do not use if inner seal is missing or broken.

Keep out of reach of children.

Seals/Symbols

M(SM)

Storage

Keep bottle tightly closed.

Store in a cool, dry place.

Brand IP Statement(s)

Mannatech, Stylized M Design and GI-Zyme are trademarks of Mannatech, Incorporated. 2014 Mannatech, Incorporated. All rights reserved.

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

FDA Statement of Identity

DIETARY SUPPLEMENT

General

Product Number 13201 US.13201.24.006

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

See for yourself

GI-Zyme by Mannatech label

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

GI-Zyme 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-Zyme by Mannatech

These are the 12 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule 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.

Proprietary Herbal Blend

150 mg per serving

Proprietary Phase 1 Enzyme Blend

96 mg per serving
  • › Amylase
  • › Protease
  • › Lactase
  • › Invertase
  • › Alpha-Galactosidase

Proprietary Phase 2 Enzyme Blend

70 mg per serving
  • › Lipase
  • › Cellulase
  • › Peptidase

Beet Fiber

Interacts with
861 drugs
44 mg per serving

Beet, especially beetroot juice, is a nitrate-rich food that may modestly lower blood pressure and slightly improve exercise performance in some peopl...

Beet Fiber monograph & interactions

Other (inactive) ingredients: Vegetable Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

GI-Zyme by Mannatech Drug Interactions

Want to check YOUR meds against GI-Zyme?

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
1,150Drugs
939 Moderate 211 Minor

Ingredients driving the most interactions

Ginger 1,007
Beet Fiber 861
Peppermint 796
Fennel 740

Individual Drug Interactions

The ingredients in GI-Zyme interact with 1,150 drugs. Click any drug to see the details.

4 of the 12 ingredients in GI-Zyme interact with drugs. Each result below shows which ingredient is responsible. Ginger Beet Fiber Peppermint Fennel

Each ingredient & the kinds of drugs it affects

For each ingredient in GI-Zyme 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.

Ginger14 drug types · 1,007 drugs

Anticoagulant/Antiplatelet Drugs

Ginger may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs. However, research is conflicting.
Laboratory research suggests that ginger inhibits thromboxane synthetase and decreases platelet aggregation. However, this has not been demonstrated unequivocally in humans, with mixed results from clinical trials. Theoretically, excessive amounts of ginger might increase the risk of bleeding when used with anticoagulant/antiplatelet drugs.

Likelihood Possible Evidence B
Antidiabetes Drugs

Theoretically, taking ginger with antidiabetes drugs might increase the risk of hypoglycemia.
Animal and human research suggests that ginger might increase insulin levels and/or decrease blood glucose levels.

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

Ginger might increase or decrease the levels of CYP3A4 substrates.
In vitro research and some case reports suggest that ginger inhibits CYP3A4 activity. Three case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are CYP3A4 substrates (imatinib, dabrafenib, and crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration.
Conversely, other in vitro research suggests that ginger induces CYP3A4 activity, leading to reduced levels of CYP3A4 substrates. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Losartan (Cozaar)

Theoretically, ginger might increase levels of losartan and the risk of hypotension.
In animal research, ginger increased the levels and hypotensive effects of a single dose of losartan. It is not clear if ginger alters the concentration or effects of losartan when taken continuously. Additionally, this interaction has not been shown in humans.

Likelihood Possible Evidence D
Nifedipine (Procardia)

Ginger may have antiplatelet effects and increase the risk of bleeding if used with nifedipine.
Clinical research shows that combined treatment with ginger 1 gram plus nifedipine 10 mg significantly inhibits platelet aggregation when compared to nifedipine or ginger alone.

Likelihood Possible Evidence B
P-Glycoprotein Substrates

Ginger might increase the absorption and blood levels of P-glycoprotein (P-gp) substrates.
In vitro research and case reports suggest that ginger inhibits drug efflux by P-gp, potentially increasing absorption and serum levels of P-gp substrates. Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are P-gp substrates (trametinib, crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration.

Likelihood Possible Evidence D
Phenprocoumon (Marcoumar, Others)

Ginger might increase the risk of bleeding with phenprocoumon.
Phenprocoumon, a warfarin-related anticoagulant, might increase the international normalized ratio (INR) when taken with ginger. There is one case report of a 76-year-old woman with a stable INR on phenprocoumon that increased to greater than 10 when she began consuming dried ginger and ginger tea.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Ginger might increase the risk of bleeding with warfarin.
Laboratory research suggests that ginger might inhibit thromboxane synthetase and decrease platelet aggregation. In one case report, ginger increased the INR when taken with phenprocoumon, which has similar pharmacological effects as warfarin. In another case report, ginger increased the INR when taken with a combination of warfarin, hydrochlorothiazide, and acetaminophen. A longitudinal analysis suggests that taking ginger increases the risk of bleeding in patients taking warfarin for at least 4 months. However, research in healthy people suggests that ginger has no effect on INR, or the pharmacokinetics or pharmacodynamics of warfarin. Until more is known, monitor INRs closely in patients taking large amounts of ginger.

Likelihood Possible Evidence B
Calcium Channel Blockers

Theoretically, taking ginger with calcium channel blockers might increase the risk of hypotension.
Some animal and in vitro research suggests that ginger has hypotensive and calcium channel-blocking effects. Another animal study shows that concomitant administration of ginger and the calcium channel blocker amlodipine leads to greater reductions in blood pressure when compared with amlodipine alone.

Likelihood Unlikely Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, when taken prior to cyclosporine, ginger might decrease cyclosporine levels.
In an animal model, ginger juice taken 2 hours prior to cyclosporine administration reduced the maximum concentration and area under the curve of cyclosporine by 51% and 40%, respectively. This effect was not observed when ginger juice and cyclosporine were administered at the same time.

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

Theoretically, ginger might increase the levels of CYP1A2 substrates.
In vitro research shows that ginger inhibits CYP1A2 activity. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2B6 (Cyp2B6) Substrates

Theoretically, ginger might increase the levels of CYP2B6 substrates.
In vitro research shows that ginger inhibits CYP2B6 activity. However, this interaction has not been reported in humans.

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

Theoretically, ginger might increase the levels of CYP2C9 substrates.
In vitro research shows that ginger inhibits CYP2C9 activity. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Metronidazole (Flagyl)

Theoretically, ginger might increase levels of metronidazole.
In an animal model, ginger increased the absorption and plasma half-life of metronidazole. In addition, the elimination rate and clearance of metronidazole was significantly reduced.

Likelihood Possible Evidence D
Ginger full monograph & interactions

Beet Fiber3 drug types · 861 drugs

Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, beet might increase the levels of CYP3A4 substrates.
In vitro research suggests that betanin, the major pigment in beet, competitively inhibits CYP3A4 in a dose-dependent manner similarly to strong CYP3A4 inhibitor ketoconazole.

Likelihood Possible Evidence D
Antihypertensive Drugs

Beet and beetroot contain nitrates, which can cause vasodilation, potentially leading to lower blood pressure. However, a study published in the European Journal of Clinical Nutrition using concentrated beetroot juice found no significant impact on blood pressure or heart rate in different age groups. Other small clinical studies suggest that while beet consumption might transiently lower blood pressure due to vessel dilation, there's no consistent evidence of a lasting effect. Overall, the theoretical risk of reduced blood pressure due to beet's nitrate content exists, but studies generally indicate a low and temporary impact rather than a sustained decrease.

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

Theoretically, beet might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research suggests that beet induces CYP1A2 enzymes.

Likelihood Possible Evidence D
Beet Fiber full monograph & interactions

Peppermint5 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 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
The maker

Brand information

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

Mannatech

See all Mannatech products
Name
Mannatech, Incorporated.
Street Address
600 S. Royal Ln., Ste. 200
City
Coppell
State
TX
ZipCode
95019
Web Address
mannatech.com
Pharmacist Counseling Corner

GI-Zyme by Mannatech: Common Questions

Does GI-Zyme by Mannatech interact with any medications?
Yes. Based on its ingredients, GI-Zyme has a known interaction with 1,150 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
GI-Zyme contains 12 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 lactase in this product effective for lactose intolerance?
Yes. Lactase is rated effective for lactose intolerance. It helps your body digest milk sugar if you have trouble doing so naturally.
Can I take this during pregnancy?
Lactase is likely safe in pregnancy, and ginger is likely safe at typical doses. However, fennel and peppermint oil in concentrated supplement form should be avoided during pregnancy due to limited safety data—talk with your doctor first about whether this product is right for you.
Is peppermint in this product effective for IBS or indigestion?
Peppermint is likely effective for irritable bowel syndrome (IBS) and possibly effective for indigestion (dyspepsia), so it may help with those conditions.
What are the most common side effects?
Digestive discomfort—such as abdominal pain, diarrhea, heartburn, belching, and nausea—is the most common side effect. Beet may also cause red or black stools, which is harmless. Ginger at higher doses carries more risk of these effects.
Why does this product have so many ingredient interactions?
Fennel, ginger, peppermint, and beet fiber contain active compounds that change how your liver and body process certain medications. These are well-researched plant ingredients, so we have detailed interaction data for them—but that's a sign to check your prescriptions rather than a reason to avoid the product.
Is it safe to take this while breastfeeding?
Lactase is generally well tolerated while breastfeeding, and peppermint is likely safe. Ginger is likely safe at food amounts. Fennel, however, should be avoided in medicinal or concentrated amounts because there's not enough safety data—check with your doctor or pharmacist first.

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-Zyme label
Go deeper

The Full Monographs Behind GI-Zyme’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

Ginger

Interacts with 1,007 drugs

Ginger is a widely used culinary spice with a long history in traditional medicine, and it has the strongest evidence for helping with nausea and vomiting, including from motion sickness, pr...

Read the full Ginger 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

Proteolytic Enzymes (proteases)

Proteolytic enzymes are proteins that help break down other proteins, and common examples include bromelain (from pineapple), papain (from papaya), trypsin, chymotrypsin, and pancreatin. Peo...

Read the full Proteolytic Enzymes (proteases) monograph → Herb & supplement monograph

Lactase

Lactase is a digestive enzyme supplement that helps people who lack enough natural lactase break down lactose, the sugar in milk and dairy. It can reduce gas, bloating, cramping, and diarrhe...

Read the full Lactase monograph → Herb & supplement monograph

Lipase

Lipase is a digestive enzyme that helps your body break down dietary fats. It is well established as part of prescription pancreatic enzyme therapy for people who cannot make enough of their...

Read the full Lipase monograph → Herb & supplement monograph

Beet

Interacts with 861 drugs

Beet, especially beetroot juice, is a nitrate-rich food that may modestly lower blood pressure and slightly improve exercise performance in some people. It is generally safe as a food, but s...

Read the full Beet monograph →
Sources

Sources & How We Checked

GI-Zyme'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 141 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.

Proteolytic Enzymes (proteases) 3 references
  1. Weeks JA, Harper RA, Simon RA, Burdick JD. Assessment of sensitization risk of a laundry pre-spotter containing protease. Cutan Ocul Toxicol. 2011;30(4):272-9. PubMed
  2. Marquès LI, Lara S, Abós T, Bartolomé B. Occupational rhinitis due to pepsin. J Investig Allergol Clin Immunol. 2006;16(2):136-7. DOI
  3. Cartier A, Malo JL, Pineau L, Dolovich J. Occupational asthma due to pepsin. J Allergy Clin Immunol. 1984;73(5 Pt 1):574-7. PubMed

See these in context on the Proteolytic Enzymes (proteases) monograph →

Lipase 1 reference
  1. Casper C, Hascoet JM, Ertl T, et al. Recombinant bile salt-stimulated lipase in preterm infant feeding: A randomized phase 3 study. PLoS One. 2016;11(5):e0156071. PubMed

See these in context on the Lipase monograph →

Lactase 1 reference
  1. Laukkanen A, Ruoppi P, Remes S, Koistinen T, Mäkinen-Kiljunen S. Lactase-induced occupational protein contact dermatitis and allergic rhinoconjunctivitis. Contact Dermatitis. 2007;57(2):89-93. PubMed

See these in context on the Lactase monograph →

Fennel 17 references
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Ginger 64 references
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Peppermint 41 references
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Beet 14 references
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See these in context on the Beet monograph →

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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.

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