Major interaction on record — check this product against your medications before combining. Check your meds →
Dietary supplement

Reduce Ingredients & Drug Interactions

by Sugarbreak

Reduce label
See full label image
Capsule Category: Botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Reduce 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: Major

Reduce is a dietary supplement by Sugarbreak with 4 active ingredients. Its ingredients are commonly taken for blood sugar control, boosting breast milk supply, high cholesterol.Based on those ingredients, 1,391 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Green Tea leaf extract, Gymnema sylvestre leaf extract, Fenugreek seed extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Reduce by Sugarbreak

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

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Reduce by Sugarbreak

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 4 of its 4 active ingredients.
  • “Green Tea leaf extract” is listed as a grouped ingredient — the label gives one combined amount (200 mg) without saying how much of each component you get.

Sugarbreak Reduce has four active ingredients. Fenugreek seed extract, banaba leaf extract, gymnema sylvestre leaf extract, and EGCG (a compound from green tea) are the working components.

The capsule also contains inactive ingredients: rice flour, hypromellose, magnesium stearate, and silica—these are just fillers and binders to hold the capsule together.

Does it work?

Moderate 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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: support healthy blood sugar levels and weight loss.
  • We looked for evidence on: Diabetes, Impaired glucose tolerance (prediabetes), Hyperlipidemia, Obesity, Metabolic syndrome, Type 2 diabetes — and 2 related terms.
  • The strongest evidence on file: Fenugreek is rated "Possibly Effective" for Diabetes (Natural Medicines).
  • Also on file: Fenugreek is rated "Insufficient Reliable Evidence To Rate" for Hyperlipidemia, Obesity, Impaired glucose tolerance (prediabetes), Metabolic syndrome.
  • Also on file: Gymnema is rated "Insufficient Reliable Evidence To Rate" for Diabetes, Obesity.

The evidence is mixed. Fenugreek seed extract shows possibly effective ratings for sexual dysfunction, sexual arousal, dysmenorrhea (period pain), and diabetes.

Banaba leaf extract, gymnema, and EGCG all have insufficient evidence for us to rate them for the conditions this product targets—the research just isn't established well enough in our data to say whether they work. That doesn't mean they don't; it means we don't have solid proof either way.

The evidence, ingredient by ingredient Fenugreek Banaba Green Tea Gymnema

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Fenugreek is generally well tolerated in food amounts, but supplement doses can cause side effects: abdominal pain, bloating, diarrhea, gas, nausea, and low blood sugar are the most common. Rare but serious allergic reactions including severe swelling of the throat, difficulty breathing, and shock have been reported.

If you're pregnant, avoid medicinal amounts of fenugreek—it may affect the uterus. Breastfeeding mothers often use fenugreek to boost milk supply, but talk to your provider first since evidence is limited.

Banaba is generally well tolerated short-term, but long-term safety isn't established. Avoid it during pregnancy and while breastfeeding due to insufficient safety data.

Gymnema is well tolerated in the short term, but avoid it during pregnancy and breastfeeding. One rare case of liver inflammation (hepatitis) has been reported with gymnema tea, and the product's quality varies between brands.

Side effects, ingredient by ingredient Fenugreek Banaba Green Tea Gymnema

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?
  • 3 of the 3 matched ingredients can interact with medications — Fenugreek, Gymnema, Banaba.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications.
  • For scale: 1,068 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 pharmacist if you take blood thinners or antiplatelet drugs (warfarin, clopidogrel, aspirin), diabetes medications, blood pressure medications, theophylline, seizure medications like phenytoin, sildenafil, or any drug metabolized by liver enzymes. No interactions are documented for EGCG or the green tea leaf extract itself in our data.

Check your own medication Run your meds through the checker above

The bottom line

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

Sugarbreak Reduce is intended for people managing blood sugar and sexual function, but the evidence for most of its ingredients is limited or unproven. If you take any medications—especially blood thinners, diabetes drugs, blood pressure meds, seizure medications, theophylline, or sildenafil—you must check them against this product before you start.

Talk to your pharmacist or doctor about whether it's right for you, especially if you're pregnant or breastfeeding.

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

Assessment coverage: 3 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 24, 2021.

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 Reduce, straight from the product label.

Brand Sugarbreak
Barcode (UPC) 860004622826
Net contents 60 Vegan Capsule(s)
Market status On market
Date entered into DSLD Sep 24, 2021
DSLD ID 257655
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free
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 Reduce by Sugarbreak, 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:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
30
UPC/BARCODE
860004622826
IngredientAmount% DV
EGCG90 mg--
Fenugreek seed extract250 mg--
Banaba leaf extract150 mg--
Green Tea leaf extract200 mg--
Gymnema sylvestre leaf extract400 mg--

Other ingredients: Rice Flour, Hypromellose, 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.
Formulation

Take daily to support healthy blood sugar levels so you can live each day with confidence. At Sugarbreak we have one goal: for you to maintain healthy blood sugar levels using safe, clinically tested, naturally sourced ingredients. We are committed to helping you live a rich, fulfilling life with your health working for you, not against you.

Promotes healthy weight loss, healthy cholesterol levels & healthy insulin production Clinically tested ingredients

Vegan

Gluten free Allergen 8 free Non-GMO

Manufactured in the USA

Promotes healthy blood sugar levels

Suggested/Recommended/Usage/Directions

Directions: 2 capsules, once daily, best taken with food. Measure & track results.

Precautions

Warning: Please consult your healthcare provider prior to use if you are pregnant, nursing, taking any medication or if you have a medical condition.

Keep out of reach of children.

General Statements

Please recycle

FDA Statement of Identity

Dietary Supplement

Brand IP Statement(s)

GS4 Plus is a registered trademark of Sabinsa Corporation.

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.

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

See for yourself

Reduce by Sugarbreak label

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

Reduce 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 Reduce by Sugarbreak

These are the 4 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container30 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.

Fenugreek seed extract

Interacts with
389 drugs
250 mg per serving

Fenugreek is a common kitchen spice that is also taken as a supplement, mainly for blood sugar, cholesterol, and to support breast milk production. So...

Fenugreek seed extract monograph & interactions

Banaba leaf extract

Interacts with
299 drugs
150 mg per serving Form: Corosolic acids

Banaba is a leaf extract most often used to help support healthy blood sugar, and small early studies suggest its active compound corosolic acid may m...

Banaba leaf extract monograph & interactions

Green Tea leaf extract

Interacts with
1,293 drugs
200 mg per serving

Green tea is a popular beverage rich in antioxidants called catechins, and drinking it in normal amounts is considered safe for most people. Concentra...

Green Tea leaf extract monograph & interactions
  • › EGCG

Gymnema sylvestre leaf extract

Interacts with
851 drugs
400 mg per serving Form: Gymnemic Acids

Gymnema is an Ayurvedic herb best known for possibly helping lower blood sugar and reducing the taste of sweetness on the tongue. Some early human stu...

Gymnema sylvestre leaf extract monograph & interactions

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

Interaction report

Reduce by Sugarbreak Drug Interactions

Want to check YOUR meds against Reduce?

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
1,391Drugs
13 Major 1,113 Moderate 265 Minor

Ingredients driving the most interactions

Green Tea leaf extract 1,293
Gymnema sylvestre leaf extract 851
Fenugreek seed extract 389
Banaba leaf extract 299

Individual Drug Interactions

The ingredients in Reduce interact with 1,391 drugs. Click any drug to see the details.

4 of the 4 ingredients in Reduce interact with drugs. Each result below shows which ingredient is responsible. Green Tea leaf extract Gymnema sylvestre leaf extract Fenugreek seed extract Banaba leaf extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Reduce 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.

Green Tea leaf extract58 drug types · 1,293 drugs

Atorvastatin (Lipitor)

Green tea extract seems to reduce the levels and clinical effects of atorvastatin.
In healthy humans, taking green tea extract 300 mg or 600 mg along with atorvastatin reduces plasma levels of atorvastatin by approximately 24%. The elimination of atorvastatin is not affected. Atorvastatin is a substrate of organic anion-transporting polypeptides (OATPs). Research shows that two of the major catechins found in green tea, epicatechin gallate (ECG) and epigallocatechin gallate (EGCG), inhibit OATPs. Some OATPs are expressed in the small intestine and are responsible for the uptake of drugs and other compounds, which may have resulted in reduced plasma levels of atorvastatin. It is not clear if drinking green tea alters the absorption of atorvastatin.

Likelihood Likely Evidence B
Ephedrine

Theoretically, concomitant use might increase the risk for stimulant adverse effects.
Green tea contains caffeine. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death.

Likelihood Probable Evidence D
Nadolol (Corgard)

Green tea seems to reduce the levels and clinical effects of nadolol.
Preliminary clinical research shows that green tea consumption reduces plasma concentrations of nadolol. Compared to a control group, both peak levels and total drug exposure (AUC) of nadolol were reduced by approximately 85% in subjects who drank green tea daily for two weeks. Drinking green tea with nadolol also significantly reduced nadolol's systolic blood pressure lowering effect. Other clinical research shows that a single dose of green tea can affect plasma nadolol levels for at least one hour. Green tea catechins have been shown to inhibit organic anion transporting polypeptides (OATP), one of which, OATP1A2, is involved in the uptake of nadolol in the intestine The interaction is thought to be due primarily to the epigallocatechin gallate (EGCG) content of green tea.

Likelihood Likely Evidence B
5-Fluorouracil

Theoretically, high doses of green tea might increase the effects and side effects of 5-fluorouracil.
Animal research shows that taking green tea in amounts equivalent to about 6 cups daily in humans for 4 weeks prior to receiving a single injection of 5-fluorouracil increases the maximum plasma levels of 5-fluorouracil by about 2.5-fold and the area under the curve by 425%.

Likelihood Possible Evidence D
Adenosine (Adenocard)

Theoretically, green tea might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Green tea contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine doesn't seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Possible Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, green tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Conflicting reports exist regarding the effect of green tea on bleeding risk when used with anticoagulant or antiplatelet drugs; however, most evidence suggests that drinking green tea in moderate amounts is unlikely to cause a significant interaction. Green tea contains small amounts of vitamin K, approximately 7 mcg per cup. Some case reports have associated the antagonism of warfarin with the vitamin K content of green tea. However, these reports are rare, and very large doses of green tea (about 8-16 cups daily) appear to be needed to cause these effects. Furthermore, the catechins and caffeine in green tea are reported to have antiplatelet activity.

Likelihood Unlikely Evidence D
Beta-Adrenergic Agonists

Green tea contains caffeine. Theoretically, concomitant use of large amounts of caffeine might increase cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Bortezomib (Velcade)

Theoretically, green tea might interfere with the effects of bortezomib.
In vitro research shows that green tea polyphenols, such as epigallocatechin gallate (EGCG), interact with bortezomib and block its proteasome inhibitory action. This prevents the induction of cell death in multiple myeloma or glioblastoma cancer cell lines. Advise patients taking bortezomib, not to take green tea.

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

Theoretically, green tea might reduce the effects of carbamazepine and increase the risk for convulsions.
Green tea contains caffeine. Animal research suggests that taking caffeine can lower the anticonvulsant effects of carbamazepine and can induce seizures when taken in doses above 400 mg/kg. Human research has shown that taking caffeine 300 mg in three divided doses along with carbamazepine 200 mg reduces the bioavailability of carbamazepine by 32% and prolongs the plasma half-life of carbamazepine 2-fold in healthy individuals.

Likelihood Possible Evidence D
Celiprolol (Celicard)

Theoretically, green tea might reduce the levels and clinical effects of celiprolol.
In a small human study, taking green tea daily for 4 days appears to decrease blood and urine levels of celiprolol by at least 98%. This interaction is possibly due to the inhibition of organic anion transporting polypeptide (OATP). Green tea catechins have been shown to inhibit organic anion transporting polypeptides (OATP), one of which, OATP1A2, is found in the intestine The interaction is thought to be due primarily to the epigallocatechin gallate (EGCG) content of green tea.

Likelihood Possible Evidence D
Cimetidine (Tagamet)

Theoretically, concomitant use might increase the effects and adverse effects of caffeine in green tea.
Green tea contains caffeine. Cimetidine can reduce caffeine clearance by 31% to 42%.

Likelihood Likely Evidence B
Clozapine (Clozaril)

Theoretically, green tea might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Animal research suggests that, although green tea extract does not affect the elimination of clozapine, it delays the time to reach peak concentration and reduces the peak plasma levels. Also, concomitant administration of green tea and clozapine might theoretically cause acute exacerbation of psychotic symptoms due to the caffeine in green tea. Caffeine can increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg daily inhibit clozapine metabolism. Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Researchers speculate that caffeine might inhibit CYP1A2. However, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients be more sensitive to the interaction between clozapine and caffeine.

Likelihood Possible Evidence B
Contraceptive Drugs

Theoretically, concomitant use might increase the effects and adverse effects of caffeine found in green tea.
Green tea contains caffeine. Oral contraceptives can decrease caffeine clearance by 40% to 65%.

Likelihood Probable Evidence B
Cytochrome P450 1A2 (Cyp1A2) Inhibitors

Theoretically, concomitant use might increase the levels and adverse effects of caffeine.
Green tea contains caffeine. Caffeine is metabolized by cytochrome P450 1A2 (CYP1A2),. Theoretically, drugs that inhibit CYP1A2 may decrease the clearance rate of caffeine from green tea and increase caffeine levels.

Likelihood Possible Evidence D
Dipyridamole (Persantine)

Theoretically, green tea might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Green tea contains caffeine. Caffeine might inhibit dipyridamole-induced vasodilation. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. Methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram might increase the risk of adverse effects from caffeine.
In human research, disulfiram decreases the clearance and increases the half-life of caffeine.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, using green tea with diuretic drugs might increase the risk of hypokalemia.
Green tea contains caffeine. In excessive amounts, caffeine can reduce potassium levels due to stimulation of the sodium-potassium pump. Diuretics can also cause lower potassium levels.

Likelihood Possible Evidence D
Estrogens

Theoretically, estrogens might increase the levels and adverse effects of caffeine.
Green tea contains caffeine. Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Ethosuximide (Zarontin)

Theoretically, green tea might reduce the effects of ethosuximide and increase the risk for convulsions.
Green tea contains caffeine. Animal research suggests that caffeine 92.4 mg/kg can decrease the anticonvulsant activity of ethosuximide. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Felbamate (Felbatol)

Theoretically, green tea might reduce the effects of felbamate and increase the risk for convulsions.
Green tea contains caffeine. Animal research suggests that a high dose of caffeine 161.7 mg/kg can decreases the anticonvulsant activity of felbamate. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Fexofenadine (Allegra)

Green tea can decrease blood levels of fexofenadine.
Clinical research shows that green tea can significantly decrease blood levels and excretion of fexofenadine. Taking green tea extract with a dose of fexofenadine decreased bioavailability of fexofenadine by about 30%. In vitro, green tea inhibits the cellular accumulation of fexofenadine by inhibiting the organic anion transporting polypeptide (OATP) drug transporter. Research shows that two of the major catechins found in green tea, epicatechin gallate (ECG) and epigallocatechin gallate (EGCG), inhibit OATPs, specifically OATP1A2, OATP1B1, and OATP2B1. In addition, green tea has been shown to reduce the absorption of some drugs that are OATP substrates.

Likelihood Probable Evidence B
Flutamide (Eulexin)

Theoretically, green tea might increase the levels and adverse effects of flutamide.
Green tea contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide. Theoretically, concomitant use of caffeine and flutamide might increase serum concentrations of flutamide and increase the risk adverse effects.

Likelihood Possible Evidence D
Fluvoxamine (Luvox)

Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
Green tea contains caffeine. Fluvoxamine reduces caffeine metabolism.

Likelihood Probable Evidence D
Hepatotoxic Drugs

Theoretically, concomitant use might have additive adverse hepatotoxic effects.
Green tea extract supplements have been linked to several cases of hepatotoxicity and might have additive hepatotoxic effects with other drugs..

Likelihood Unlikely Evidence D
Imatinib (Gleevec)

Theoretically, green tea might reduce the levels and clinical effects of imatinib.
In animal research, a single dose of green tea extract reduces the area under the curve (AUC) of imatinib by up to approximately 64% and its main metabolite N-desmethyl imatinib by up to approximately 81%. This interaction has not been shown in humans. The mechanism of action is unclear but may involve multiple pathways.

Likelihood Possible Evidence D
Green Tea leaf extract full monograph & all 58 interactions

Gymnema sylvestre leaf extract6 drug types · 851 drugs

Antidiabetes Drugs

Theoretically, taking gymnema with antidiabetes drugs might increase the risk of hypoglycemia.
Gymnema reduces blood glucose levels in some human and animal research. In human studies, it has been shown to enhance the blood glucose lowering effects of hypoglycemic drugs. However, other research in adults with prediabetes or metabolic syndrome suggests that gymnema does not reduce fasting levels of blood glucose. Until more is known, monitor blood glucose levels closely.

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

Theoretically, gymnema might increase levels of drugs metabolized by CYP1A2.
Animal and in vitro research shows that gymnema can inhibit the CYP1A2 enzyme. In one animal study, oral administration of gymnema for 7 days increased the plasma concentrations of phenacetin, a CYP1A2 substrate, by about 1.4-fold and reduced the clearance of phenacetin by about 29%.

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

Theoretically, gymnema might increase or decrease levels of drugs metabolized by CYP2C9.
Animal research shows that gymnema can induce the CYP2C9 enzyme. In one animal study, gymnema caused a 2.4-fold increase in the clearance of tolbutamide, a CYP2C9 substrate, in rats. In vitro research also shows that gymnema can inhibit CYP2C9.

Likelihood Possible Evidence D
Phenacetin

Theoretically, taking gymnema with phenacetin might increase the levels of phenacetin.
Animal research shows that gymnema, administered orally for 7 days, decreases the clearance of phenacetin in a dose-dependent manner by about 21% to 29% and increases plasma levels about 1.3- to 1.4-fold when compared to control.

Likelihood Possible Evidence D
Tolbutamide (Orinase)

Theoretically, taking gymnema with tolbutamide might the decrease levels of tolbutamide.
Animal research shows that gymnema, administered orally for 7 days, increases the clearance of tolbutamide by 2.4-fold when compared to control.

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

Theoretically, gymnema might increase levels of drugs metabolized by CYP3A4.
One in vitro study using rat liver microsomes shows that gymnema can modestly inhibit the CYP3A4 enzyme. However, other in vitro research using human liver microsomes shows that gymnema does not affect CYP3A4 activity. Animal research also shows that gymnema does not alter the function of CYP3A4. In one study in rats, oral administration of gymnema for 7 days did not alter the clearance of amlodipine, a CYP3A4 substrate.

Likelihood Unlikely Evidence D
Gymnema sylvestre leaf extract full monograph & interactions

Fenugreek seed extract9 drug types · 389 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, fenugreek might have additive effects when used with anticoagulant or antiplatelet drugs.
Some of the constituents in fenugreek have antiplatelet effects in animal and in vitro research. However, common fenugreek products might not contain sufficient concentrations of these constituents for clinical effects. A clinical study in patients with coronary artery disease or diabetes shows that taking fenugreek seed powder 2.5 grams twice daily for 3 months does not affect platelet aggregation, fibrinolytic activity, or fibrinogen levels .

Likelihood Unlikely Evidence B
Antidiabetes Drugs

Theoretically, fenugreek seed might have additive hypoglycemic effects when used with antidiabetes drugs.
Clinical research shows that fenugreek seed can reduce fasting blood glucose and 2-hour postprandial glucose levels in adults with type 2 diabetes.

Likelihood Probable Evidence B
Clopidogrel (Plavix)

Theoretically, fenugreek seed might alter the clinical effects of clopidogrel by inhibiting its conversion to the active form.
Animal research shows that fenugreek seed 200 mg/kg daily for 14 days increases the maximum serum concentration of clopidogrel by 21%. It is unclear how this affects the pharmacokinetics of the active metabolite of clopidogrel; however, this study found that concomitant use of fenugreek seed and clopidogrel prolonged bleeding time by an additional 11%.

Likelihood Possible Evidence D
Metoprolol (Toprol)

Theoretically, fenugreek seed might have additive hypotensive effects when used with metoprolol.
Animal research shows that fenugreek seed 300 mg/kg daily for 2 weeks decreases systolic and diastolic blood pressure by 9% and 11%, respectively, when administered alone, and by 15% and 22%, respectively, when given with metoprolol 10 mg/kg.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, fenugreek might decrease plasma levels of phenytoin.
Animal research shows that taking fenugreek seeds for 1 week decreases maximum concentrations and the area under the curve of a single dose of phenytoin by 44% and 72%, respectively. This seems to be related to increased clearance. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Theoretically, concurrent use of sildenafil and fenugreek might reduce levels and therapeutic effects of sildenafil.
Animal research shows that taking fenugreek seeds for 1 week reduces maximum concentrations and the area under the curve of a single dose of sildenafil by 27% and 48%, respectively. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Theophylline

Theoretically, fenugreek may reduce the levels and clinical effects of theophylline.
Animal research shows that fenugreek 50 grams daily for 7 days reduces the maximum serum concentration (Cmax) of theophylline by 28% and the area under the plasma drug concentration-time curve (AUC) by 22%.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, fenugreek might have additive effects with warfarin and increase the international normalized ratio (INR).
Some fenugreek constituents have antiplatelet effects, although these might not be present in concentrations that are clinically significant. In one case report, a patient taking warfarin experienced an increased INR when starting to take fenugreek in combination with boldo.

Likelihood Possible Evidence D
Antihypertensive Drugs

Fenugreek may also have an additive effect on blood pressure-lowering medications. Studies on animals have shown that fenugreek seed can decrease both systolic and diastolic blood pressure by up to 22% when combined with metoprolol. Therefore, it is essential to monitor your blood pressure regularly if you are taking fenugreek and metoprolol together or any other antihypertensive drugs.

Likelihood Possible Evidence C
Fenugreek seed extract full monograph & interactions

Banaba leaf extract3 drug types · 299 drugs

Antidiabetes Drugs

Theoretically, concomitant use of banaba and hypoglycemic drugs might have additive effects.
Human and animal research suggests that banaba can lower blood glucose levels.

Likelihood Probable Evidence B
Antihypertensive Drugs

Theoretically, concomitant use of banaba and antihypertensive drugs might cause additive effects.
Human and animal research suggests that banaba can lower blood pressure.

Likelihood Probable Evidence B
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Theoretically, concomitant use of banaba with substrates of OATP might reduce the bioavailability of the OATP substrate.
In vitro research shows that banaba inhibits OATP, particularly OATP2B1. OATPs are expressed in the small intestine and liver and are responsible for the absorption of drugs and other compounds.

Likelihood Possible Evidence D
Banaba leaf extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Reduce, from the product label.

Sugarbreak

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Name
Sugarbreak
Street Address
907 Broadway
City
New York
State
NY
ZipCode
10010
Web Address
www.sugarbreak.com
Pharmacist Counseling Corner

Reduce by Sugarbreak: Common Questions

Does Reduce by Sugarbreak interact with any medications?
Yes. Based on its ingredients, Reduce has a known interaction with 1,391 medications, including 13 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Reduce contains 4 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.
What is fenugreek seed extract, and what's it supposed to do?
Fenugreek is an herb used in cooking and supplements. In this product, it's meant to help with sexual dysfunction, sexual arousal, period pain, and blood sugar control—the research suggests it may be helpful for these, but it's not definitive.
Can I take this if I'm pregnant?
Avoid medicinal amounts of fenugreek during pregnancy because it may affect the uterus. There isn't enough safety data on banaba or gymnema during pregnancy either, so it's best to skip this product and talk to your doctor or midwife instead.
Can I take this while breastfeeding?
Fenugreek is often used to boost milk supply, but the evidence is limited—discuss it with your provider first. There's no reliable safety information for banaba or gymnema while breastfeeding, so avoid those.
What are the most common side effects?
From fenugreek, you might notice stomach upset, gas, bloating, diarrhea, nausea, or low blood sugar. Allergic reactions are rare but can be serious. Banaba and gymnema can cause dizziness, headache, and tremor in some people.
Does this product have fillers?
Yes—like most capsules, it contains rice flour, hypromellose, magnesium stearate, and silica to hold everything together.
Is there good evidence that this actually works for blood sugar?
Fenugreek has some research showing it may help, but banaba and gymnema don't have enough reliable evidence yet for us to say they work. Talk to your doctor about whether this should replace your regular diabetes management.

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.

Reduce label
Go deeper

The Full Monographs Behind Reduce’s Ingredients

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

Herb & supplement monograph

Fenugreek

Interacts with 389 drugs

Fenugreek is a common kitchen spice that is also taken as a supplement, mainly for blood sugar, cholesterol, and to support breast milk production. Some early research is encouraging for blo...

Read the full Fenugreek monograph → Herb & supplement monograph

Banaba

Interacts with 299 drugs

Banaba is a leaf extract most often used to help support healthy blood sugar, and small early studies suggest its active compound corosolic acid may modestly lower glucose. The overall evide...

Read the full Banaba monograph → Herb & supplement monograph

Green Tea

Interacts with 1,293 drugs

Green tea is a popular beverage rich in antioxidants called catechins, and drinking it in normal amounts is considered safe for most people. Concentrated green tea extracts are a different s...

Read the full Green Tea monograph → Herb & supplement monograph

Gymnema

Interacts with 851 drugs

Gymnema is an Ayurvedic herb best known for possibly helping lower blood sugar and reducing the taste of sweetness on the tongue. Some early human studies are encouraging for blood sugar sup...

Read the full Gymnema monograph →
Sources

Sources & How We Checked

Reduce'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 268 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.

Fenugreek 30 references
  1. Madar Z, Thorne R. Dietary fiber. Prog Food Nutr Sci 1987;11:153-74.
  2. Sharma RD, Raghuram TC, Rao NS. Effect of fenugreek seeds on blood glucose and serum lipids in type I diabetes. Eur J Clin Nutr 1990;44:301-6.
  3. Patil SP, Niphadkar PV, Bapat MM. Allergy to fenugreek (Trigonella foenum graecum). Ann Allergy Asthma Immunol 1997;78:297-300. PubMed
  4. Lambert J, Cormier J. Potential interaction between warfarin and boldo-fenugreek. Pharmacotherapy 2001;21:509-12. PubMed
  5. Bordia A, Verma SK, Srivastava KC. Effect of ginger (Zingiber officinale Rosc.) and fenugreek (Trigonella foenumgraecum L.) on blood lipids, blood sugar and platelet aggregation in patients with coronary artery disease. Prostaglandins Leukot Essent Fatty PubMed
  6. Yalcin SS, Tekinalp G, Ozalp I. Peculiar odor of traditional food and maple syrup urine disease. Pediatr Int 1999;41:108-9. PubMed
  7. Sewell AC, Mosandl A, Bohles H. False diagnosis of maple syrup urine disease owing to ingestion of herbal tea. N Engl J Med 1999;341:769.. PubMed
  8. Abdo MS, al-Kafawi AA. Experimental studies on the effect of Trigonella foenum-graecum (abstract). Planta Med 1969;17:14-8.
  9. Gupta A, Gupta R, Lal B. Effect of Trigonella foenum-graecum (fenugreek) seeds on glycaemic control and insulin resistance in type 2 diabetes mellitus: a double blind placebo controlled study. J Assoc Physicians India 2001;49:1057-61.
  10. Gabay MP. Galactogogues: medications that induce lactation. J Hum Lact 2002;18:274-9. PubMed
  11. Chevassus H, Gaillard JB, Farret A, et al. A fenugreek seed extract selectively reduces spontaneous fat intake in overweight subjects. Eur J Clin Pharmacol 2010;66(5):449-55. PubMed
  12. Turkyilmaz C, Onal E, Hirfanoglu IM, et al. The effect of galactagogue herbal tea on breast milk production and short-term catch-up of birth weight in the first week of life. J Altern Complement Med 2011;17(2):139-42. PubMed
  13. Swafford S, Berens P. Effect of fenugreek on breast milk volume. Abstract presented at: 5th International Meeting of the Academy of Breastfeeding Medicine; September 11-13,2000, Tucson, Arizona.
  14. Abdel-Barry, J. A., Abdel-Hassan, I. A., Jawad, A. M., and al Hakiem, M. H. Hypoglycaemic effect of aqueous extract of the leaves of Trigonella foenum-graecum in healthy volunteers. East Mediterr.Health J 2000;6(1):83-88. DOI
  15. Parvizpur, A., Ahmadiani, A., and Kamalinejad, M. Probable role of spinal purinoceptors in the analgesic effect of Trigonella foenum (TFG) leaves extract. J Ethnopharmacol 3-8-2006;104(1-2):108-112. PubMed
  16. Mora, A., Herrrera, A., Lopez, C., Dahbi, G., Mamani, R., Pita, J. M., Alonso, M. P., Llovo, J., Bernardez, M. I., Blanco, J. E., Blanco, M., and Blanco, J. Characteristics of the Shiga-toxin-producing enteroaggregative Escherichia coli O104:H4 German ou
  17. Blanco, J. [Stx2a-producing enteroaggregative Escherichia coli O104:H4-ST678. Microbiological diagnostic already, for this and other STEC/VTEC serotypes!]. Enferm.Infecc.Microbiol.Clin. 2012;30(2):84-89.
  18. Beutin, L. and Martin, A. Outbreak of Shiga toxin-producing Escherichia coli (STEC) O104:H4 infection in Germany causes a paradigm shift with regard to human pathogenicity of STEC strains. J Food Prot. 2012;75(2):408-418. PubMed
  19. King LA, Nogareda F, Weill FX, Mariani-Kurkdjian P, Loukiadis E, Gault G, Jourdan-DaSilva N, Bingen E, Macé M, Thevenot D, Ong N, Castor C, Noël H, Van Cauteren D, Charron M, Vaillant V, Aldabe B, Goulet V, Delmas G, Couturier E, Le Strat Y, Combe C, Delm
  20. Reeder C, Legrand A, O'Connor-Von SK. The Effect of Fenugreek on Milk Production and Prolactin Levels in Mothers of Preterm Infants. Clinical Lactation 2013;4(4):159-165. DOI
  21. Al-Jenoobi FI, Ahad A, Mahrous GM, Al-Mohizea AM, AlKharfy KM, Al-Suwayeh SA. Effects of fenugreek, garden cress, and black seed on theophylline pharmacokinetics in beagle dogs. Pharm Biol 2015;53(2):296-300. PubMed
  22. Rao A, Steels E, Inder WJ, Abraham S, Vitetta L. Testofen, a specialised Trigonella foenum-graecum seed extract reduces age-related symptoms of androgen decrease, increases testosterone levels and improves sexual function in healthy aging males in a doubl
  23. Steels E, Rao A, Vitetta L. Physiological aspects of male libido enhanced by standardized Trigonella foenum-graecum extract and mineral formulation. Phytother Res. 2011 Sep;25(9):1294-300.
  24. Gong J, Fang K, Dong H, Wang D, Hu M, Lu F. Effect of fenugreek on hyperglycaemia and hyperlipidemia in diabetes and prediabetes: A meta-analysis. J Ethnopharmacol. 2016 Dec 24;194:260-268. PubMed
  25. Ouzir M, El Bairi K, Amzazi S. Toxicological properties of fenugreek (Trigonella foenum graecum). Food Chem Toxicol. 2016 Oct;96:145-54. PubMed
  26. Khodamoradi K, Khosropanah MH, Ayati Z, et al. The Effects of Fenugreek on Cardiometabolic Risk Factors in Adults: A Systematic Review and Meta-analysis. Complement Ther Med. 2020;52:102416. PubMed
  27. Alkharfy K, Jan B, Alotaibi K, et al. Clopidogrel-herb Interactions: A Pharmacokinetic and Pharmacodynamic Assessment in a Rat Model. Curr Drug Metab 2021;22(12):969-977. PubMed
  28. Bin Jardan YA, Ahad A, Raish M, Alam MA, Al-Mohizea AM, Al-Jenoobi FI. Effects of garden cress, fenugreek and black seed on the pharmacodynamics of metoprolol: an herb-drug interaction study in rats with hypertension. Pharm Biol 2021;59(1):1088-1097. PubMed
  29. Al-Mohizea AM, Ahad A, El-Maghraby GM, et al. Effects of Nigella sativa, Lepidium sativum and Trigonella foenum-graecum on sildenafil disposition in beagle dogs. Eur J Drug Metab Pharmacokinet. 2015;40(2):219-24. PubMed
  30. Alkharfy KM, Al-Jenoobi FI, Al-Mohizea AM, et al. Effects of Lepidium sativum, Nigella sativa and Trigonella foenum-graceum on phenytoin pharmacokinetics in beagle dogs. Phytother Res. 2013;27(12):1800-4.

See these in context on the Fenugreek monograph →

Banaba 7 references
  1. Judy WV, Hari SP, Stogsdill WW, et al. Antidiabetic activity of a standardized extract (Glucosol) from Lagerstroemia speciosa leaves in Type II diabetics. A dose-dependence study. J Ethnopharmacol 2003;87:115-7. PubMed
  2. Kakuda T, Sakane I, Takihara T, et al. Hypoglycemic effect of extracts from Lagerstroemia speciosa L. leaves in genetically diabetic KK-AY mice. Biosci Biotechnol Biochem 1996;60:204-8.
  3. Fukushima, M., Matsuyama, F., Ueda, N., Egawa, K., Takemoto, J., Kajimoto, Y., Yonaha, N., Miura, T., Kaneko, T., Nishi, Y., Mitsui, R., Fujita, Y., Yamada, Y., and Seino, Y. Effect of corosolic acid on postchallenge plasma glucose levels. Diabetes Res C PubMed
  4. Yamaguchi, Y., Yamada, K., Yoshikawa, N., Nakamura, K., Haginaka, J., and Kunitomo, M. Corosolic acid prevents oxidative stress, inflammation and hypertension in SHR/NDmcr-cp rats, a model of metabolic syndrome. Life Sci 11-25-2006;79(26):2474-2479. PubMed
  5. Fuchikami H, Satoh H, Tsujimoto M, Ohdo S, Ohtani H, Sawada Y. Effects of herbal extracts on the function of human organic anion-transporting polypeptide OATP-B. Drug Metab Dispos 2006;34:577-82. PubMed
  6. Manaf A, Tjandrawinata RR, Malinda D. Insulin sensitizer in prediabetes: a clinical study with DLBS3233, a combined bioactive fraction of Cinnamomum burmanii and Lagerstroemia speciosa. Drug Des Devel Ther. 2016;10:1279-89. PubMed
  7. Tjokroprawiro A, Murtiwi S, Tjandrawinata RR. DLBS3233, a combined bioactive fraction of Cinnamomum burmanii and Lagerstroemia speciosa, in type-2 diabetes mellitus patients inadequately controlled by metformin and other oral antidiabetic agents. J Comple

See these in context on the Banaba monograph →

Green Tea 219 references
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  2. Harder S, Fuhr U, Staib AH, Wolff T. Ciprofloxacin-caffeine: a drug interaction established using in vivo and in vitro investigations. Am J Med 1989;87:89S-91S. PubMed
  3. Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40. PubMed
  4. Healy DP, Polk RE, Kanawati L, et al. Interaction between oral ciprofloxacin and caffeine in normal volunteers. Antimicrob Agents Chemother 1989;33:474-8. PubMed
  5. Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37:348-50. PubMed
  6. Jefferson JW. Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988;49:72-3.
  7. Mitscher LA, Mitscher LA, Jung M, Shankel D, et al. Chemoprotection: a review of the potential therapeutic antioxidant properties of green tea (Camellia sinensis) and certain of its constituents. Med Res Rev 1997;17:327-65.
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  9. Vahedi K, Domingo V, Amarenco P, Bousser MG. Ischemic stroke in a sportsman who consumed MaHuang extract and creatine monohydrate for bodybuilding. J Neurol Neurosurg Psychiatr 2000;68:112-3.
  10. Wakabayashi K, Kono S, Shinchi K, et al. Habitual coffee consumption and blood pressure: A study of self-defense officials in Japan. Eur J Epidemiol 1998;14:669-73. PubMed
  11. Hodgson JM, Puddey IB, Burke V, et al. Effects on blood pressure of drinking green and black tea. J Hypertens 1999;17:457-63. PubMed
  12. Booth SL, Madabushi HT, Davidson KW, et al. Tea and coffee brews are not dietary sources of vitamin K-1 (phylloquinone). J Am Diet Assoc 1995;95:82-3. PubMed
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See these in context on the Green Tea monograph →

Gymnema 12 references
  1. Shanmugasundaram ER, Rajeswari G, Baskaran K, et al. Use of Gymnema sylvestre leaf extract in the control of blood glucose in insulin-dependent diabetes mellitus. J Ethnopharmacol 1990;30:281-94. PubMed
  2. Baskaran K, Kizar Ahamath B, Radha Shanmugasundaram K, Shanmugasundaram ER. Antidiabetic effect of leaf extract from Gymnema sylvestre in non-insulin-dependent diabetes mellitus patients. J Ethnopharmacol 1990;30:295-300.
  3. Kamble B, Gupta A, Moothedath I, Khatal L, Janrao S, Jadhav A, et al. Effects of Gymnema sylvestre extract on the pharmacokinetics and pharmacodynamics of glimepiride in streptozotocin induced diabetic rats. Chem Biol Interact. 2016;245:30-8. PubMed
  4. Tiwari P, Mishra BN, Sangwan NS. Phytochemical and pharmacological properties of Gymnema sylvestre: an important medicinal plant. Biomed Res Int. 2014; 2014:830285.
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See these in context on the Gymnema 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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