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

Berberine GT Ingredients & Drug Interactions

by Metagenics

Berberine GT label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Berberine GT 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

Berberine GT is a dietary supplement by Metagenics with 2 active ingredients. Its ingredients are commonly taken for blood sugar control, high cholesterol, heart and metabolic health.Based on those ingredients, 1,478 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Green Tea Leaf Extract, Berberine Hydrochloride. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Berberine GT by Metagenics

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

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HelloPharmacist Scorecard of Berberine GT by Metagenics

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 3 of its 3 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.

Berberine GT contains 3 active ingredients. The main one is berberine hydrochloride, a plant alkaloid.

The other two are epigallocatechin gallate and catechins, both compounds from green tea leaf extract known for their antioxidant properties. The capsule also contains inactive ingredients — hydroxypropyl methylcellulose, microcrystalline cellulose, magnesium stearate, and silica — which are standard binders and fillers.

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 LDL and glucose metabolism.
  • We looked for evidence on: Hyperlipidemia, Diabetes, Impaired glucose tolerance (prediabetes), Metabolic syndrome, Cardiovascular disease (CVD), Coronary heart disease (CHD) — and 4 related terms.
  • The strongest evidence on file: Berberine is rated "Possibly Effective" for Diabetes (Natural Medicines).
  • Also on file: Berberine is rated "Possibly Effective" for Hyperlipidemia, Polycystic ovary syndrome (PCOS).
  • Also on file: Berberine is rated "Insufficient Reliable Evidence To Rate" for Cardiovascular disease (CVD), Metabolic dysfunction-associated steatotic liver disease (MASLD), Coronary heart disease (CHD), Nonalcoholic fatty liver disease (NAFLD).

The evidence we have shows berberine is possibly effective for several conditions. Clinical research suggests it may help lower cholesterol (hyperlipidemia), reduce blood pressure (hypertension), and improve blood sugar control in diabetes.

There's also possibly effective evidence for polycystic ovary syndrome (PCOS) and for helping clear Helicobacter pylori bacterial infection. Keep in mind that 'possibly effective' means the research is promising but not yet conclusive — talk with your doctor about whether this supplement makes sense for your situation.

The evidence, ingredient by ingredient Berberine Green Tea

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

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

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

Berberine is generally well tolerated when taken by mouth short-term, but digestive side effects are common — expect potential abdominal pain, bloating, constipation, diarrhea, gas, nausea, or vomiting. You may also experience dizziness, drowsiness, fatigue, or headache.

The safety data advises against berberine during pregnancy because it can cross the placenta and has been linked to harm in newborns, and it should not be used while breastfeeding since it passes into breast milk.

Side effects, ingredient by ingredient Berberine Green Tea

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Berberine.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications.
  • For scale: 1,161 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 take this product, check with your pharmacist if you take cyclosporine (Major severity interaction). You should also double-check if you use blood pressure medications, blood thinners or antiplatelet drugs, diabetes medications, or any drug broken down by your liver — berberine can affect how many of these work.

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. Major medication interactions have been identified, and safety information is well characterized.

Berberine GT may be worth considering if you're looking to support cholesterol, blood pressure, or blood sugar — but only if you don't take cyclosporine or other medications that interact heavily with berberine. Anyone on prescription drugs needs to check their exact medications with our tool before starting.

Talk with your pharmacist to make sure it's right for you.

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

Assessment coverage: 1 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 25, 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 Berberine GT, straight from the product label.

Brand Metagenics
Barcode (UPC) 755571954381
Net contents 60 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Mar 25, 2025
DSLD ID 323329
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegetarian, Adult (18 - 50 Years), Women (not pregnant or lactating), 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 Berberine GT by Metagenics, 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 Vegetarian Capsule(s)
Maximum serving Sizes:
1 Vegetarian Capsule(s)
Servings per container
60
UPC/BARCODE
755571954381
IngredientAmount% DV
Epigallocatechin Gallate80 mg--
Catechins120 mg--
Berberine Hydrochloride500 mg--
Green Tea Leaf Extract200 mg--

Other ingredients: Hydroxypropyl Methylcellulose, Microcrystalline Cellulose, Magnesium Stearate, Silica

Tap any ingredient to jump to its full detail below.

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

Berberine GT features berberine, an alkaloid compound found in the roots, rhizomes, stems and bark of several plants commonly used in botanical and Chinese medicine for centuries. Berberine supports healthy LDL and glucose metabolism, and cardiovascular health. Berberine GT also features green tea, which has numerous clinical studies demonstrating benefits to the cardiovascular system.

Suggested/Recommended/Usage/Directions

Directions: Take one capsule two to three times daily or as directed by your healthcare practitioner.

Formulation

This product is non-GMO, gluten-free, and vegetarian.

This product is non-GMO, gluten-free, and vegetarian.

GFCO.org (Gluten-Free Certification Organization)

Supports healthy glucose metabolism and cardiovascular health

Precautions

Warning: Do not use if pregnant or nursing. Caution: If taking medications, including cyclosporine and oral antidiabetic medications, or other nutritional supplements consult your healthcare practitioner before use.

Keep out of the reach of children.

Tamper evident: Do not use if safety seal is missing or broken.

Practitioner Exclusive

Storage

Storage: Keep tightly closed in a cool, dry place.

Seals/Symbols

GFCO.org (Gluten-Free Certification Organization)

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

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

See for yourself

Berberine GT by Metagenics label

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

Berberine GT 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 Berberine GT by Metagenics

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Vegetarian 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.

Berberine Hydrochloride

Interacts with
1,160 drugs
500 mg per serving Form: Phellodendron amurense bark extract

Berberine is a yellow plant compound that has shown promise for lowering blood sugar and cholesterol in some studies, but the quality of research vari...

Berberine Hydrochloride monograph & interactions

Green Tea Leaf Extract

Interacts with
1,293 drugs
200 mg per serving Form: Camellia sinensis Leaf Extract

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
  • › Epigallocatechin Gallate
  • › Catechins

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

Interaction report

Berberine GT by Metagenics Drug Interactions

Want to check YOUR meds against Berberine GT?

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
1,478Drugs
14 Major 1,454 Moderate 10 Minor

Ingredients driving the most interactions

Green Tea Leaf Extract 1,293
Berberine Hydrochloride 1,160

Individual Drug Interactions

The ingredients in Berberine GT interact with 1,478 drugs. Click any drug to see the details.

2 of the 2 ingredients in Berberine GT interact with drugs. Each result below shows which ingredient is responsible. Green Tea Leaf Extract Berberine Hydrochloride

Each ingredient & the kinds of drugs it affects

For each ingredient in Berberine GT 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

Berberine Hydrochloride15 drug types · 1,160 drugs

Cyclosporine (Neoral, Sandimmune)

Berberine can increase serum levels of cyclosporine.
Berberine can reduce metabolism and increase serum levels of cyclosporine. Berberine might inhibit cytochrome P450 3A4 (CYP3A4), which metabolizes cyclosporine.

Likelihood Probable Evidence A
Anticoagulant/Antiplatelet Drugs

Theoretically, berberine might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
In vitro and in vivo research suggest that berberine can inhibit platelet aggregation. Theoretically, berberine might have additive effects when used with anticoagulant and antiplatelet drugs and increase the risk of bleeding.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, berberine may increase the risk of hypoglycemia when taken with antidiabetes drugs.
Clinical research shows that berberine may lower blood glucose levels. Theoretically, berberine might have additive effects with antidiabetes drugs and increase the risk of hypoglycemia.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, berberine might have additive effects with antihypertensive drugs.
Animal research suggests that berberine can have hypotensive effects. Also, a clinical study suggests that taking berberine in combination with amlodipine can lower systolic and diastolic blood pressure when compared with amlodipine alone.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, berberine might increase the sedative effects of CNS depressants.
Animal research suggests that berberine may have sedative effects. Theoretically, use of berberine along with CNS depressants might produce additive therapeutic and adverse effects.

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

Theoretically, berberine might increase serum levels of drugs metabolized by CYP2C9.
Preliminary clinical research shows that berberine can inhibit CYP2C9. Theoretically, taking berberine with drugs metabolized by CYP2C9 might increase drug levels and increase the risk of adverse effects.

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

Theoretically, berberine might increase serum levels of drugs metabolized by CYP2D6.
In vitro research and preliminary clinical evidence show that berberine can inhibit CYP2D6. Theoretically, use of berberine with drugs metabolized by CYP2D6 might increase drug levels and increase the risk of adverse effects.

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

Theoretically, berberine might increase serum levels of drugs metabolized by CYP3A4.
In vitro research and preliminary clinical research show that berberine moderately inhibits CYP3A4. Theoretically, use of berberine with drugs metabolized by CYP3A4 might increase drug levels and increase the risk of adverse effects.

Likelihood Possible Evidence A
Dextromethorphan (Robitussin Dm, Others)

Theoretically, berberine may increase serum levels of dextromethorphan.
Preliminary clinical research shows that berberine can inhibit cytochrome P450 2D6 (CYP2D6) activity and reduce the metabolism of dextromethorphan. This may increase the effects and side effects of dextromethorphan.

Likelihood Possible Evidence B
Losartan (Cozaar)

Berberine might reduce the therapeutic effects of losartan by decreasing its conversion to its active form.
Preliminary clinical research suggests that berberine can inhibit cytochrome P450 2C9 (CYP2C9) activity and reduce metabolism of losartan.

Likelihood Possible Evidence B
Metformin (Glucophage)

Theoretically, berberine might increase the therapeutic and adverse effects of metformin.
In vitro and animal studies show that berberine can increase the systemic exposure and half-life of metformin, potentially increasing metformin's effects and side effects. This interaction seems to be most apparent when berberine is administered 2 hours prior to metformin. Taking berberine and metformin at the same time does not appear to increase systemic exposure to metformin.

Likelihood Possible Evidence D
Midazolam (Versed)

Berberine can reduce metabolism of midazolam, which might increase the risk of severe adverse effects.
Preliminary clinical research shows that berberine can inhibit cytochrome P450 3A4 (CYP3A4) activity and reduce metabolism of midazolam.

Likelihood Possible Evidence B
Pentobarbital (Nembutal)

Berberine might increase the sedative effect of pentobarbital.
Evidence from animal research shows that berberine can prolong pentobarbital-induced sleeping time. Theoretically, combining berberine and pentobarbital might increase the sedative effects of pentobarbital.

Likelihood Possible Evidence D
Tacrolimus (Prograf)

Berberine has been associated with increased blood levels of tacrolimus.
In a 16-year-old patient with idiopathic nephrotic syndrome who was being treated with tacrolimus 6.5 mg twice daily, intake of berberine 200 mg three times daily increased the blood concentration of tacrolimus from 8 to 22 ng/mL. Following a reduction of the tacrolimus dose to 3 mg daily, blood levels of tacrolimus decreased to 12 ng/mL.

Likelihood Possible Evidence D
Acetazolamide

Laboratory studies and initial clinical findings suggest that berberine has the potential to increase acetazolamide concentrations in the body. More research is needed to confirm this interaction.

Likelihood Possible Evidence C
Berberine Hydrochloride full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Berberine GT, from the product label.

Metagenics

See all Metagenics products
Name
Metagenics
City
Gig Harbor
State
WA
ZipCode
98332
Phone Number
800 692 9400
Web Address
metagenics.com
Pharmacist Counseling Corner

Berberine GT by Metagenics: Common Questions

Does Berberine GT by Metagenics interact with any medications?
Yes. Based on its ingredients, Berberine GT has a known interaction with 1,478 medications, including 14 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Berberine GT contains 2 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.
Can I take Berberine GT if I'm pregnant or breastfeeding?
No. Berberine should be avoided during pregnancy — the safety data shows it can cross the placenta and has been linked to harm in newborns. It should also be avoided while breastfeeding because it passes into breast milk. If you're planning pregnancy or are already pregnant or nursing, talk with your doctor before taking any berberine supplement.
What side effects might I experience?
Digestive upset is the most common issue — abdominal pain, bloating, constipation, diarrhea, gas, nausea, or vomiting. You might also feel dizzy, drowsy, tired, or get a headache. Most people tolerate it short-term, but if these bother you, talk with your pharmacist about dosing or timing.
Does berberine actually work for blood sugar and cholesterol?
The research shows it's possibly effective for both. Clinical studies suggest berberine may lower cholesterol and help control blood sugar in diabetes, and there's possibly effective evidence for blood pressure and PCOS too. But 'possibly effective' means promising, not proven — ask your doctor whether this supplement fits your treatment plan.
What's in this product besides berberine?
The active ingredients are berberine hydrochloride and compounds from green tea leaf extract — epigallocatechin gallate and catechins, which are antioxidants. The rest is inactive fillers like cellulose and silica that hold the capsule together.
Why do I need to check my medications before taking this?
Berberine blocks several liver enzymes that break down many common drugs, which can raise drug levels in your blood and cause side effects. It also adds to the effects of blood pressure and diabetes medications. The interaction with cyclosporine is especially serious. Your pharmacist can tell you whether your specific prescriptions are affected.

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

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The Full Monographs Behind Berberine GT’s Ingredients

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

Herb & supplement monograph

Berberine

Interacts with 1,160 drugs

Berberine is a yellow plant compound that has shown promise for lowering blood sugar and cholesterol in some studies, but the quality of research varies and it is not a replacement for presc...

Read the full Berberine 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 →
Sources

Sources & How We Checked

Berberine GT'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 260 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.

Berberine 41 references
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  4. Zhang Y, Li X, Zou D, et al. Treatment of type 2 diabetes and dyslipidemia with the natural plant alkaloid berberine. J Clin Endocrinol Metab 2008;93:2559-65. PubMed
  5. Huang XS, Yang GF, Pan YC. Effect of berberin hydrochloride on blood concentration of cyclosporine A in cardiac transplanted patients. Zhongguo Zhong Xi Yi Jie He Za Zhi 2008;28:702-4.
  6. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed
  7. Chatterjee P, Franklin MR. Human cytochrome p450 inhibition and metabolic-intermediate complex formation by goldenseal extract and its methylenedioxyphenyl components. Drug Metab Dispos 2003;31:1391-7. PubMed
  8. Marin-Neto, J. A., Maciel, B. C., Secches, A. L., and Gallo, Junior L. Cardiovascular effects of berberine in patients with severe congestive heart failure. Clin.Cardiol. 1988;11(4):253-260. PubMed
  9. Choudhry, V. P., Sabir, M., and Bhide, V. N. Berberine in giardiasis. Indian Pediatr. 1972;9(3):143-146.
  10. Shanbhag, S. M., Kulkarni, H. J., and Gaitonde, B. B. Pharmacological actions of berberine on the central nervous system. Jpn.J Pharmacol 1970;20(4):482-487. PubMed
  11. Wu, J. F. and Liu, T. P. [Effects of berberine on platelet aggregation and plasma levels of TXB2 and 6-keto-PGF1 alpha in rats with reversible middle cerebral artery occlusion]. Yao Xue.Xue.Bao. 1995;30(2):98-102.
  12. Peng, W. H., Hsieh, M. T., and Wu, C. R. Effect of long-term administration of berberine on scopolamine-induced amnesia in rats. Jpn J Pharmacol 1997;74(3):261-266. DOI
  13. Sharda DC. Berberine in the treatment of diarrhoea of infancy and childhood. J Indian M A 1970;54(1):22-24.
  14. Sabir M and Bhide NK. Study of some pharmacological actions of berberine. Ind J Physiol & Pharmac 1971;15(3):111-132.
  15. Tripathi YB and Shukla SD. Berberis artistata inhibits PAF induced aggregation of rabbit platelets. Phytotherapy Research 1996;10:628-630.
  16. Seery TM and Bieter RN. A contribution to the pharmacology of berberine. J Pharmacol Exp Ther 1940;69:64-67. DOI
  17. Xin, H. W., Wu, X. C., Li, Q., Yu, A. R., Zhong, M. Y., and Liu, Y. Y. The effects of berberine on the pharmacokinetics of cyclosporin A in healthy volunteers. Methods Find.Exp.Clin Pharmacol 2006;28(1):25-29.
  18. Zhang, Y., Li, X., Zou, D., Liu, W., Yang, J., Zhu, N., Huo, L., Wang, M., Hong, J., Wu, P., Ren, G., and Ning, G. Treatment of type 2 diabetes and dyslipidemia with the natural plant alkaloid berberine. J Clin Endocrinol.Metab 2008;93(7):2559-2565. PubMed
  19. Yin, J., Xing, H., and Ye, J. Efficacy of berberine in patients with type 2 diabetes mellitus. Metabolism 2008;57(5):712-717. PubMed
  20. Zhang, H., Wei, J., Xue, R., Wu, J. D., Zhao, W., Wang, Z. Z., Wang, S. K., Zhou, Z. X., Song, D. Q., Wang, Y. M., Pan, H. N., Kong, W. J., and Jiang, J. D. Berberine lowers blood glucose in type 2 diabetes mellitus patients through increasing insulin re
  21. Guo, Y., Chen, Y., Tan, Z. R., Klaassen, C. D., and Zhou, H. H. Repeated administration of berberine inhibits cytochromes P450 in humans. Eur J Clin Pharmacol 2012;68(2):213-217. PubMed
  22. Wei, W., Zhao, H., Wang, A., Sui, M., Liang, K., Deng, H., Ma, Y., Zhang, Y., Zhang, H., and Guan, Y. A clinical study on the short-term effect of berberine in comparison to metformin on the metabolic characteristics of women with polycystic ovary syndro
  23. Marazzi, G., Cacciotti, L., Pelliccia, F., Iaia, L., Volterrani, M., Caminiti, G., Sposato, B., Massaro, R., Grieco, F., and Rosano, G. Long-term effects of nutraceuticals (berberine, red yeast rice, policosanol) in elderly hypercholesterolemic patients. PubMed
  24. Meng, S., Wang, L. S., Huang, Z. Q., Zhou, Q., Sun, Y. G., Cao, J. T., Li, Y. G., and Wang, C. Q. Berberine ameliorates inflammation in patients with acute coronary syndrome following percutaneous coronary intervention. Clin Exp.Pharmacol Physiol 2012;39 PubMed
  25. Hermann, R. and von, Richter O. Clinical evidence of herbal drugs as perpetrators of pharmacokinetic drug interactions. Planta Med 2012;78(13):1458-1477. PubMed
  26. Chun YT, Yip TT, Lau KL, and et al. A biochemical study on the hypotensive effect of berberine in rats. Gen Pharmac 1979;10:177-182. PubMed
  27. Saksena HC, Tomar VN, and Soangra MR. Efficacy of a new salt of Berberine Uni-Berberine in oriental sore. Current Medical Practice 1970;14:247-252.
  28. Abascal K, Yarnell E. Recent clinical advances with berberine. Altern Complement Ther 2010;16(5):281-7. DOI
  29. Dong H, Zhao Y, Zhao L, Lu F. The effects of berberine on blood lipids: a systemic review and meta-analysis of randomized controlled trials. Planta Med 2013;79(6):437-46. PubMed
  30. Hou Q, Han W, Fu X. Pharmacokinetic interaction between tacrolimus and berberine in a child with idiopathic nephrotic syndrome. Eur J Clin Pharmacol 2013;69(10):1861-2. PubMed
  31. Lan J, Zhao Y, Dong F, et al. Meta-analysis of the effect and safety of berberine in the treatment of type 2 diabetes mellitus, hyperlipemia and hypertension. J Ethnopharmacol. 2015;161:69-81. PubMed
  32. Li G, Zhao M, Qiu F, Sun Y, Zhao L. Pharmacokinetic interactions and tolerability of berberine chloride with simvastatin and fenofibrate: an open-label, randomized, parallel study in healthy Chinese subjects. Drug Des Devel Ther. 2018;13:129-139. PubMed
  33. Ju J, Li J, Lin Q, Xu H. Efficacy and safety of berberine for dyslipidaemias: A systematic review and meta-analysis of randomized clinical trials. Phytomedicine. 2018;50:25-34. PubMed
  34. Xu L, Zhang Y, Xue X, et al. A phase I trial of berberine in Chinese with ulcerative colitis. Cancer Prev Res (Phila). 2020;13(1):117-26. PubMed
  35. Lyu Y, Zhang Y, Yang M, et al. Pharmacokinetic interactions between metformin and berberine in rats: Role of oral administration sequences and microbiota. Life Sci. 2019;235:116818. PubMed
  36. Chen YX, Gao QY, Zou TH, et al. Berberine versus placebo for the prevention of recurrence of colorectal adenoma: a multicentre, double-blinded, randomised controlled study. Lancet Gastroenterol Hepatol. 2020;5(3):267-75. PubMed
  37. Zhang J, Wang Y, Jiang H, et al. Preventive effect of berberine on postoperative atrial fibrillation. Circ Arrhythm Electrophysiol 2022;15(10):e011160. PubMed
  38. Blais JE, Huang X, Zhao JV. Overall and Sex-Specific Effect of Berberine for the Treatment of Dyslipidemia in Adults: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Trials. Drugs 2023;83(5):403-427. PubMed
  39. Panigrahi A, Mohanty S. Efficacy and safety of HIMABERB® Berberine on glycemic control in patients with prediabetes: double-blind, placebo-controlled, and randomized pilot trial. BMC Endocr Disord 2023;23(1):190. PubMed
  40. Nie Q, Li M, Huang C, et al. The clinical efficacy and safety of berberine in the treatment of non-alcoholic fatty liver disease: a meta-analysis and systematic review. J Transl Med 2024;22(1):225. PubMed
  41. Koperska A, Moszak M, Seraszek-Jaros A, Bogdanski P, Szulinska M. Does berberine impact anthropometric, hepatic, and metabolic parameters in patients with metabolic dysfunction-associated fatty liver disease? Randomized, double-blind placebo-controlled tr

See these in context on the Berberine monograph →

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  218. Zhao H, Zhu W, Zhao X, et al. Efficacy of epigallocatechin-3-gallate in preventing dermatitis in patients with breast cancer receiving postoperative radiotherapy: A double-blind, placebo-controlled, phase 2 randomized clinical trial. JAMA Dermatol 2022;15 PubMed
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See these in context on the Green Tea 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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