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

GlycoLog Ingredients & Drug Interactions

by Blackstone Labs

GlycoLog 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 GlycoLog 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

GlycoLog is a dietary supplement by Blackstone Labs with 7 active ingredients. Its ingredients are commonly taken for blood sugar support in type 2 diabetes, weight loss and appetite control, insulin sensitivity.Based on those ingredients, 1,318 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Super Berberine, BioPerine Black Pepper (fruit) extract, Gymnema extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against GlycoLog by Blackstone Labs

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

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of GlycoLog by Blackstone Labs

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 Aug 6, 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 7 of its 7 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

GlycoLog contains seven active ingredients. Chromium is a mineral that may help manage blood glucose levels.

Super Berberine is an alkaloid extract traditionally used for metabolic support. Sodium R-Lipoate (also called alpha-lipoic acid) is an antioxidant compound.

BioPerine is a black pepper fruit extract standardized for piperine, which enhances absorption of other nutrients. Gymnema is a plant extract traditionally used in metabolic health.

Bitter melon is a vegetable extract also used for metabolic support. Cinnamon extract (Ceylon cinnamon) is derived from cinnamon bark.

The capsules also contain inactive ingredients: gelatin, magnesium stearate, silicon dioxide, and titanium dioxide.

Does it work?

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

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

Why this rating?
  • The label markets this product for: blood sugar control and insulin sensitivity.
  • We looked for evidence on: Diabetes, Impaired glucose tolerance (prediabetes), Hyperlipidemia, Hypertriglyceridemia, Chromium deficiency, Metabolic syndrome — and 2 related terms.
  • The strongest evidence on file: Chromium is rated "Likely Effective" for Chromium deficiency (Natural Medicines).
  • Also on file: Alpha-lipoic Acid is rated "Possibly Effective" for Hyperlipidemia.
  • Also on file: Chromium is rated "Possibly Effective" for Diabetes.

The evidence for GlycoLog's ingredients is mixed. Chromium is likely effective for chromium deficiency and possibly effective for diabetes, though it's rated possibly ineffective for prediabetes.

Berberine is possibly effective for high cholesterol, PCOS, H. pylori infection, high blood pressure, and diabetes. Alpha-lipoic acid is possibly effective for diabetic nerve pain, high cholesterol, and obesity.

Black pepper extract, cinnamon, gymnema, and bitter melon all lack sufficient reliable evidence to rate their effectiveness for the conditions this product targets — meaning the research we have isn't strong enough to draw clear conclusions about how well they work.

The evidence, ingredient by ingredient Chromium Berberine Alpha-lipoic Acid Black Pepper Gymnema Bitter Melon Ceylon Cinnamon

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

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

Why this rating?
  • We hold adverse-effect (side-effect) data for 7 of the 7 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 7 of 7.
  • General safety write-ups exist for 7 of 7.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most of these ingredients are generally well tolerated at typical supplement doses. Chromium commonly causes gastrointestinal irritation, headaches, insomnia, and mood changes; rare serious effects include kidney or liver damage and blood disorders.

Berberine often causes digestive upset (nausea, diarrhea, constipation, abdominal pain) and should be avoided in pregnancy and while breastfeeding because it may cross the placenta and appear in breast milk. Alpha-lipoic acid may cause headache, nausea, heartburn, or rash and should be avoided during pregnancy and lactation due to insufficient safety data.

Black pepper is safe in food amounts but concentrated supplements should be used cautiously. Gymnema may cause liver inflammation (hepatitis) in rare cases and should be avoided during pregnancy and lactation.

Bitter melon commonly causes stomach upset and may lower blood sugar; seeds and high doses are traditionally avoided in pregnancy. Cinnamon is generally safe as a spice but supplement doses are less studied; rare cases of bleeding have been reported.

Side effects, ingredient by ingredient Chromium Berberine Alpha-lipoic Acid Black Pepper Gymnema Bitter Melon Ceylon Cinnamon

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?
  • 7 of the 7 matched ingredients can interact with medications — Ceylon Cinnamon, Alpha-lipoic Acid, Bitter Melon, Black Pepper, Gymnema, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; cancer treatments; diabetes medications; lithium.
  • For scale: 1,319 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 GlycoLog, double-check with your doctor or pharmacist if you take any of these: cyclosporine (immunosuppressant) — berberine raises its blood levels (Major concern); diabetes drugs or insulin — chromium, berberine, alpha-lipoic acid, gymnema, bitter melon, and cinnamon all theoretically increase low blood sugar risk; blood pressure medications — berberine and cinnamon may lower blood pressure further; blood thinners or antiplatelet drugs like warfarin or aspirin — berberine and alpha-lipoic acid may increase bleeding risk; thyroid hormone (levothyroxine) — chromium and alpha-lipoic acid may reduce its absorption or effect; drugs metabolized by your liver (such as many antidepressants, beta-blockers, statins, and antihistamines) — berberine, gymnema, and black pepper may raise their blood levels; sedating drugs (CNS depressants) — berberine may add to drowsiness; chemotherapy or cancer drugs — alpha-lipoic acid's antioxidant effects might interfere; propranolol, phenytoin, theophylline, rifampin, or nevirapine — black pepper extract may raise their levels.

Check your own medication Run your meds through the checker above

The bottom line

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

GlycoLog is designed to support blood glucose and metabolic health through a multi-ingredient approach, but its ingredients — especially berberine and gymnema — interact with many medications and carry documented side effects. If you take diabetes drugs, insulin, blood pressure medications, blood thinners, cyclosporine, or anything your liver metabolizes, you need to check with your doctor or pharmacist before starting.

Pregnant and breastfeeding people should avoid berberine and should talk with their healthcare provider about the other ingredients. Even if none of those apply to you, discuss this product with your own healthcare provider before you begin.

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

Assessment coverage: 7 of 7 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 23, 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 GlycoLog, straight from the product label.

Brand Blackstone Labs
Barcode (UPC) 636823236519
Net contents 180 Capsule(s)
Market status On market
Date entered into DSLD Aug 23, 2021
DSLD ID 256623
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 GlycoLog by Blackstone Labs, 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:
3 Capsule(s)
Maximum serving Sizes:
3 Capsule(s)
Servings per container
60
UPC/BARCODE
636823236519
IngredientAmount% DV
Chromium300 mcg250%
Super Berberine300 mg--
Sodium R-Lipoate150 mg--
BioPerine Black Pepper (fruit) extract5 mg--
Gymnema extract1000 mg--
Bitter Melon500 mg--
Cinnamon extract250 mg--

Other ingredients: Gelatin, Magnesium Stearate, Silicon Dioxide, Titanium Dioxide

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.
Precautions

Warning: This product is intended to be consumed by healthy adults 18 years of age or older. This product should only be used under medical or dietetic supervision. This product is not intended as a sole source of nutrition and should be consumed in conjunction with an appropriate physical training or exercise program.

This product is not suitable for children under 18 years of age or pregnant or nursing women. Keep out of reach of children.

This product is not suitable for children under 18 years of age or pregnant or nursing women.

Allergen Warning: Manufactured on shared equipment that also processes eggs, wheat, & soy (lecithin).

Suggested/Recommended/Usage/Directions

Directions: Take three (3) capsules with a high-carb meal, twice a day. Do not exceed six (6) capsules per day.

Formulation

Extreme insulin mimetic & nutrient partitioning agent

Maximizes insuling utilization Increases insulin sensitivity Improves glucose metabolism Enhances fat loss Stimulates glycogen storage

FDA Statement of Identity

Dietary Supplement

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

GlycoLog by Blackstone Labs label

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

GlycoLog 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 GlycoLog by Blackstone Labs

These are the 7 active ingredients this product is made of. Select any to open its full monograph.

Serving size3 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.

Chromium

Interacts with
178 drugs
300 mcg per serving Form: Chromium Picolinate

Chromium is an essential trace mineral involved in how the body handles sugar and fat. Some studies suggest it may modestly help blood sugar control i...

Chromium monograph & interactions

Super Berberine

Interacts with
1,160 drugs
300 mg per serving

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...

Super Berberine monograph & interactions

Sodium R-Lipoate

Interacts with
263 drugs
150 mg per serving

Alpha-lipoic acid (ALA) is an antioxidant made naturally by the body and found in small amounts in foods. It is most studied for diabetic nerve pain,...

Sodium R-Lipoate monograph & interactions

BioPerine Black Pepper (fruit) extract

Interacts with
1,019 drugs
5 mg per serving Form: Piperine

Black pepper is a common kitchen spice that is generally safe in the amounts used in food. Its extract, piperine, is mostly added to supplements to he...

BioPerine Black Pepper (fruit) extract monograph & interactions

Gymnema extract

Interacts with
851 drugs
1000 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 extract monograph & interactions

Bitter Melon

Interacts with
282 drugs
500 mg per serving Form: Bitters

Bitter melon is a tropical fruit eaten as food and used in traditional medicine, most often for blood sugar control. While some small studies hint it...

Bitter Melon monograph & interactions

Cinnamon extract

Interacts with
258 drugs
250 mg per serving Form: Polyphenols

Ceylon cinnamon is the so-called 'true' cinnamon, valued as a spice and used in traditional medicine for blood sugar, cholesterol, and digestion. Evid...

Cinnamon extract monograph & interactions

Other (inactive) ingredients: Gelatin, Magnesium Stearate, Silicon Dioxide, Titanium Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

GlycoLog by Blackstone Labs Drug Interactions

Want to check YOUR meds against GlycoLog?

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
1,318Drugs
1 Major 1,296 Moderate 21 Minor

Ingredients driving the most interactions

Super Berberine 1,160
BioPerine Black Pepper (fruit) extract 1,019
Gymnema extract 851
Bitter Melon 282
Sodium R-Lipoate 263

Individual Drug Interactions

The ingredients in GlycoLog interact with 1,318 drugs. Click any drug to see the details.

7 of the 7 ingredients in GlycoLog interact with drugs. Each result below shows which ingredient is responsible. Super Berberine BioPerine Black Pepper (fruit) extract Gymnema extract Bitter Melon Sodium R-Lipoate Cinnamon extract Chromium

Each ingredient & the kinds of drugs it affects

For each ingredient in GlycoLog 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.

Super Berberine15 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
Super Berberine full monograph & interactions

BioPerine Black Pepper (fruit) extract17 drug types · 1,019 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, black pepper might increase the risk of bleeding when taken with antiplatelet or anticoagulant drugs.
In vitro research shows that piperine, a constituent of black pepper, seems to inhibit platelet aggregation. This has not been reported in humans.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, black pepper might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research shows that piperine, a constituent of black pepper, can reduce blood glucose levels. Monitor blood glucose levels closely. Dose adjustments might be necessary.

Likelihood Possible Evidence D
Atorvastatin (Lipitor)

Theoretically, black pepper might increase blood levels of atorvastatin.
Animal research shows that taking piperine, a constituent of black pepper, 35 mg/kg can increase the maximum serum concentration of atorvastatin three-fold. This has not been reported in humans.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, black pepper might increase the effects and side effects of cyclosporine.
In vitro research shows that piperine, a constituent of black pepper, increases the bioavailability of cyclosporine. This has not been reported in humans.

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

Theoretically, black pepper might increase levels of drugs metabolized by CYP2D6.
In vitro research suggests that some constituents of black pepper inhibit CYP2D6. This has not been reported in humans.

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

Theoretically, black pepper might increase levels of drugs metabolized by CYP3A4.
In vitro research and pharmacokinetic simulation data suggest that piperine, a constituent of black pepper, as well as the pepper fruit seem to inhibit CYP3A4. This has not been reported in humans.

Likelihood Possible Evidence D
Lithium

Theoretically, black pepper might increase blood levels of lithium due to its diuretic effects. The dose of lithium might need to be reduced.
Black pepper is thought to have diuretic properties.

Likelihood Probable Evidence D
Nevirapine (Viramune)

Black pepper might increase blood levels of nevirapine.
Clinical research shows that piperine, a constituent of black pepper, increases the plasma concentration of nevirapine. However, no adverse effects were observed in this study.

Likelihood Probable Evidence D
P-Glycoprotein Substrates

Theoretically, black pepper might increase levels of P-glycoprotein substrates.
In vitro research shows that piperine, a constituent of black pepper, seems to inhibit P-glycoprotein.

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

Theoretically, black pepper might increase the sedative effects of pentobarbital.
Animal research shows that piperine, a constituent of black pepper, increases pentobarbital-induced sleeping time.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

Black pepper might increase blood levels of phenytoin.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption, slow elimination, and increase levels of phenytoin. Taking a single dose of black pepper 1 gram along with phenytoin seems to double the serum concentration of phenytoin. Consuming a soup with black pepper providing piperine 44 mg/200 mL of soup along with phenytoin also seems to increase phenytoin levels when compared with consuming the same soup without black pepper.

Likelihood Possible Evidence B
Propranolol (Inderal)

Black pepper might increase blood levels of propranolol.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of propranolol.

Likelihood Possible Evidence B
Rifampin (Rifadin)

Black pepper might increase blood levels of rifampin.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and serum levels of rifampin.

Likelihood Possible Evidence B
Theophylline

Black pepper might increase blood levels of theophylline.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of theophylline.

Likelihood Possible Evidence D
Amoxicillin (Amoxil, Trimox)

Theoretically, black pepper might increase the effects and side effects of amoxicillin.
Animal research shows that taking piperine, a constituent of black pepper, with amoxicillin increases plasma levels of amoxicillin. This has not been reported in humans.

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

Theoretically, black pepper might increase blood levels of carbamazepine, potentially increasing the effects and side effects of carbamazepine.
One clinical study in patients taking carbamazepine 300 mg or 500 mg twice daily shows that taking a single 20 mg dose of purified piperine, a constituent of black pepper, increases carbamazepine levels. Piperine may increase carbamazepine absorption by increasing blood flow to the GI tract, increasing the surface area of the small intestine, or inhibiting cytochrome P450 3A4 (CYP3A4) in the gut wall. Absorption was significantly increased by 7-10 mcg/mL/hour. The time to eliminate carbamazepine was also increased by 4-8 hours. Although carbamazepine levels were increased, this did not appear to increase side effects. In vitro research also shows that piperine can increase carbamazepine levels by 11% in a time-dependent manner.

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

Theoretically, black pepper might decrease levels and clinical effects of drugs metabolized by CYP1A2.
In vitro research suggests that black pepper induces CYP1A2. This has not been reported in humans.

Likelihood Possible Evidence D
BioPerine Black Pepper (fruit) extract full monograph & interactions

Gymnema 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 extract full monograph & interactions

Bitter Melon3 drug types · 282 drugs

Antidiabetes Drugs

Taking bitter melon with antidiabetes drugs might increase the risk of hypoglycemia.
Bitter melon can lower blood glucose levels and might have additive effects when used with antidiabetes drugs. This might increase the risk of hypoglycemia in some patients. Monitor blood glucose levels closely.

Likelihood Probable Evidence B
P-Glycoprotein Substrates

Theoretically, bitter melon might increase levels of P-glycoprotein substrates.
Bitter melon might inhibit the p-glycoprotein (P-gp) intestinal pump and increase intracellular levels of P-gp substrates. In vitro research in intestinal cells shows that 1-monopalmitin, a constituent of bitter melon, increases levels of daunomycin, a P-gp substrate. Additionally, drinking bitter melon juice has been associated with a case of acute pancreatitis in a patient who had been taking pazopanib, a P-gp substrate, for 8 years. Researchers theorize that inhibition of P-gp led to increased levels of pazopanib, resulting in pazopanib-induced pancreatitis.

Likelihood Possible Evidence D
Pazopanib (Votrient)

Theoretically, bitter melon might increase levels of pazopanib, potentially increasing the risk of adverse effects.
In one case, a 65-year-old patient taking pazopanib for 8 years for renal cell carcinoma experienced signs and symptoms consistent with acute pancreatitis 4 days after drinking bitter melon juice at a dose of 100-150 mL daily. The patient's symptoms, amylase levels, and lipase levels improved upon discontinuation of bitter melon and pazopanib. Pazopanib treatment was re-initiated with no further evidence of pancreatitis. Researchers theorize that inhibition of P-glycoprotein by bitter melon led to increased levels of pazopanib, a P-glycoprotein substrate, resulting in pazopanib-induced pancreatitis.

Likelihood Possible Evidence D
Bitter Melon full monograph & interactions

Sodium R-Lipoate5 drug types · 263 drugs

Alkylating Agents

Theoretically, the antioxidant effects of alpha-lipoic acid might alter the effectiveness of alkylating agents.
The use of antioxidants like alpha-lipoic acid during chemotherapy is controversial. There are concerns that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals. However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as alpha-lipoic acid have on chemotherapy. Advise patients to consult their oncologist before using alpha-lipoic acid.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, alpha-lipoic acid may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
In vitro, alpha-lipoic acid inhibits platelet aggregation.

Likelihood Possible Evidence D
Antitumor Antibiotics

Theoretically, the antioxidant effects of alpha-lipoic acid might alter the effectiveness of antitumor antibiotics.
The use of antioxidants like alpha-lipoic acid during chemotherapy is controversial. There are concerns that antioxidants could reduce the activity of antitumor antibiotic drugs, which work by generating free radicals. However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as alpha-lipoic acid have on chemotherapy involving antitumor antibiotics. Advise patients to consult their oncologist before using alpha-lipoic acid.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, alpha-lipoic acid might decrease the effects of thyroid hormone drugs.
Animal research suggests that co-administration of thyroxine with alpha-lipoic acid reduces conversion into the active T3 form.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, taking alpha-lipoic acid with antidiabetes drugs might increase the risk of hypoglycemia.
Although some small clinical studies have suggested that alpha-lipoic acid can lower blood glucose levels, larger clinical studies in patients with diabetes have shown no clinically meaningful effect. Additionally, co-administration of single doses of alpha-lipoic acid and glyburide or acarbose did not cause detectable drug interactions in healthy volunteers.

Likelihood Unlikely Evidence B
Sodium R-Lipoate full monograph & interactions

Cinnamon extract2 drug types · 258 drugs

Antidiabetes Drugs

Theoretically, Ceylon cinnamon may have additive effects with antidiabetes drugs.
Ceylon cinnamon may lower blood glucose levels. Dose adjustments might be necessary.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, Ceylon cinnamon might have additive effects with antihypertensive drugs and increase the risk of hypotension.
Animal research shows that Ceylon cinnamon extract has vasorelaxant properties and reduces blood pressure in rat models of hypertension, possibly via inhibition of calcium influx through L-type voltage-sensitive channels.

Likelihood Possible Evidence D
Cinnamon extract full monograph & interactions

Chromium5 drug types · 178 drugs

Antidiabetes Drugs

Theoretically, chromium may have additive effects with antidiabetic agents and increase the risk of hypoglycemia.
Some research shows that taking chromium might lower blood glucose levels, especially in patients with poorly controlled type 2 diabetes.

Likelihood Possible Evidence A
Insulin

Theoretically, concomitant use of chromium and insulin might increase the risk of hypoglycemia.
In clinical research, chromium has been shown to increase insulin sensitivity,

Likelihood Possible Evidence B
Levothyroxine (Synthroid, Others)

Chromium might bind levothyroxine in the intestinal tract and decrease levothyroxine absorption.
Clinical research in healthy volunteers shows that taking chromium picolinate 1000 mcg with levothyroxine 1 mg decreases serum levels of levothyroxine by 17% when compared to taking levothyroxine alone. Advise patients to take levothyroxine at least 30 minutes before or 3-4 hours after taking chromium.

Likelihood Probable Evidence B
Aspirin

Theoretically, aspirin might increase chromium absorption.
Animal research suggests that aspirin may increase chromium absorption and chromium levels in the blood.

Likelihood Possible Evidence D
Nonsteroidal Anti-Inflammatory Drugs (Nsaids)

NSAIDs might increase chromium levels in the body.
Drugs that are prostaglandin inhibitors, such as NSAIDs, seem to increase chromium absorption and retention.

Likelihood Possible Evidence D
Chromium full monograph & interactions
The maker

Brand information

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

Blackstone Labs

See all Blackstone Labs products
Name
Blackstone Labs
Phone Number
1-877-454-6861
Pharmacist Counseling Corner

GlycoLog by Blackstone Labs: Common Questions

Does GlycoLog by Blackstone Labs interact with any medications?
Yes. Based on its ingredients, GlycoLog has a known interaction with 1,318 medications, including 1 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
GlycoLog contains 7 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 GlycoLog if I'm pregnant or breastfeeding?
No — berberine is rated likely unsafe in pregnancy and lactation and should be avoided. Gymnema also lacks safety data and is best avoided. Alpha-lipoic acid and bitter melon similarly have insufficient data, so talk with your doctor before using this product while pregnant or nursing. Chromium in food amounts (like from a prenatal vitamin) is considered acceptable, but extra supplement doses should only be taken if your doctor recommends it.
What are the most common side effects I might notice?
Digestive complaints — nausea, diarrhea, constipation, abdominal pain, and heartburn — are the most common, especially from berberine and bitter melon. You may also notice headache, insomnia, mood changes, or irritability from chromium. Most people tolerate these ingredients, but if stomach upset happens, take them with food or stop and talk to your pharmacist.
Does GlycoLog actually work for blood sugar control?
Chromium is possibly effective for diabetes, and berberine has some clinical support for lowering blood glucose. Alpha-lipoic acid, gymnema, bitter melon, and cinnamon lack strong enough evidence for us to say whether they work — the research isn't clear. This isn't a replacement for prescribed diabetes medications or your doctor's guidance.
Why is berberine such a big concern?
Berberine interacts with a lot of medications because it slows down how your liver breaks down certain drugs — raising their blood levels and increasing the risk of side effects. It also theoretically adds to the effects of blood sugar and blood pressure medications. And it should be avoided entirely during pregnancy and breastfeeding.
Can I take GlycoLog with my diabetes medication?
Not without checking first. Multiple ingredients in this product — chromium, berberine, alpha-lipoic acid, gymnema, bitter melon, and cinnamon — may lower blood sugar and could theoretically add to your medication's effect, raising the risk of low blood sugar (hypoglycemia). Talk to your doctor or pharmacist before combining them.
Why does this product contain black pepper extract?
Black pepper extract (piperine) enhances the absorption and bioavailability of other nutrients in the formula, helping your body take them up more efficiently. However, this also means it can increase blood levels of certain medications you might be taking, which is why it's important to check your drug list.

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

Not sure if GlycoLog is safe with your meds?

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

GlycoLog label
Go deeper

The Full Monographs Behind GlycoLog’s Ingredients

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

Herb & supplement monograph

Chromium

Interacts with 178 drugs

Chromium is an essential trace mineral involved in how the body handles sugar and fat. Some studies suggest it may modestly help blood sugar control in certain people with type 2 diabetes, b...

Read the full Chromium monograph → 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

Alpha-lipoic Acid

Interacts with 263 drugs

Alpha-lipoic acid (ALA) is an antioxidant made naturally by the body and found in small amounts in foods. It is most studied for diabetic nerve pain, where some evidence suggests it may help...

Read the full Alpha-lipoic Acid monograph → Herb & supplement monograph

Black Pepper

Interacts with 1,019 drugs

Black pepper is a common kitchen spice that is generally safe in the amounts used in food. Its extract, piperine, is mostly added to supplements to help the body absorb other ingredients (li...

Read the full Black Pepper 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 → Herb & supplement monograph

Bitter Melon

Interacts with 282 drugs

Bitter melon is a tropical fruit eaten as food and used in traditional medicine, most often for blood sugar control. While some small studies hint it may modestly lower blood sugar, the evid...

Read the full Bitter Melon monograph → Herb & supplement monograph

Ceylon Cinnamon

Interacts with 258 drugs

Ceylon cinnamon is the so-called 'true' cinnamon, valued as a spice and used in traditional medicine for blood sugar, cholesterol, and digestion. Evidence for most health benefits is limited...

Read the full Ceylon Cinnamon monograph →
Sources

Sources & How We Checked

GlycoLog'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 223 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.

Chromium 53 references
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  2. Urberg M, Zemel MB. Evidence for synergism between chromium and nicotinic acid in the control of glucose tolerance in elderly humans. Metabolism 1987;36:896-9. PubMed
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  8. Fowler JF Jr. Systemic contact dermatitis caused by oral chromium picolinate. Cutis 2000;65:116. DOI
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  10. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
  11. Rabinovitz H, Friedensohn A, Leibovitz A, et al. Effect of chromium supplementation on blood glucose and lipid levels in type 2 diabetes mellitus elderly patients. Int J Vitam Nutr Res 2004;74:178-82. PubMed
  12. Lanca S, Alves A, Vieira AI, et al. Chromium-induced toxic hepatitis. Eur J Intern Med 2002;13:518-20. PubMed
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  15. Food Standards Agency. Medicines and Healthcare products Regulatory Agency (MHRA). Expert Group on Vitamins and Minerals. Available at: http://cot.food.gov.uk/sites/default/files/vitmin2003.pdf.
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  17. Stevens T, Qadri A, Zein NN. Two patients with acute liver injury associated with use of the herbal weight-loss supplement hydroxycut. Ann Intern Med 2005;142:477-8. PubMed
  18. Wani S, Weskamp C, Marple J, Spry L. Acute tubular necrosis associated with chromium picolinate-containing dietary supplement. Ann Pharmacother 2006;40:563-6. PubMed
  19. Kleefstra N, Houweling ST, Jansman FG, et al. Chromium treatment has no effect in patients with poorly controlled, insulin-treated type 2 diabetes in an obese Western population: a randomized, double-blind, placebo-controlled trial. Diabetes Care 2006;29: PubMed
  20. Martin J, Wang ZQ, Zhang XH, et al. Chromium picolinate supplementation attenuates body weight gain and increases insulin sensitivity in subjects with type 2 diabetes. Diabetes Care 2006;29:1826-32. PubMed
  21. Singer GM, Geohas J. The effect of chromium picolinate and biotin supplementation on glycemic control in poorly controlled patients with type 2 diabetes mellitus: a placebo-controlled, double-blinded, randomized trial. Diabetes Technol Ther 2006;8:636-43. PubMed
  22. John-Kalarickal J, Pearlman G, Carlson HE. New medications which decrease levothyroxine absorption. Thyroid 2007;17:763-5. PubMed
  23. Yazaki Y, Faridi Z, Ma Y, et al. A pilot study of chromium picolinate for weight loss. J Altern Complement Med 2010;16:291-9. PubMed
  24. Davis ML, Seaborn CD, and Stoecker BJ. Effects of over-the-counter drugs on chromium retention and urinary excretion in rats. Nutrition Research 1995;15(2):201-210.
  25. Young P, Turiansky G, Bonner M, and et al. Acute generalized exanthematous pustulosis induced by chromium picolinate. J.Am Acad.Dermatol. 1999;41(5 Pt 2):820-823. PubMed
  26. Gibb, H. J., Lees, P. S., Pinsky, P. F., and Rooney, B. C. Lung cancer among workers in chromium chemical production. Am J Ind.Med 2000;38(2):115-126. DOI
  27. Gibb, H. J., Lees, P. S., Pinsky, P. F., and Rooney, B. C. Clinical findings of irritation among chromium chemical production workers. Am J Ind.Med 2000;38(2):127-131. PubMed
  28. Pittler, M. H. and Ernst, E. Dietary supplements for body-weight reduction: a systematic review. Am.J.Clin Nutr. 2004;79(4):529-536. PubMed
  29. Pei, D., Hsieh, C. H., Hung, Y. J., Li, J. C., Lee, C. H., and Kuo, S. W. The influence of chromium chloride-containing milk to glycemic control of patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled trial. Metabolism 2 PubMed
  30. Hisatomi, K., Ishii, H., Hashiguchi, K., Seki, M., Ide, M., Sugiyama, K., Ishimoto, H., Nakayama, S., Mukae, H., and Kohno, S. Interstitial pneumonia caused by inhalation of fumes of nickel and chrome. Respirology. 2006;11(6):814-817. PubMed
  31. Kleefstra, N., Houweling, S. T., Bakker, S. J., Verhoeven, S., Gans, R. O., Meyboom-de Jong, B., and Bilo, H. J. Chromium treatment has no effect in patients with type 2 diabetes in a Western population: a randomized, double-blind, placebo-controlled tri DOI
  32. Parsons, A., Ingram, J., Inglis, J., Aveyard, P., Johnstone, E., Brown, K., Franklin, M., and Bermudez, I. A proof of concept randomised placebo controlled factorial trial to examine the efficacy of St John's wort for smoking cessation and chromium to pr
  33. Bagdon RE and Hazen RE. Skin permeation and cutaneous hypersensitivity as a basis for making risk assessments of chromium as a soil contaminant. Environ.Health Perspect. 1991;92:111-119. PubMed
  34. Bharmal, S. V., Moyes, V., Ahmed, S., and Grossman, A. Hypoglycaemia: possible mediation by chromium salt medication. Hormones.(Athens.) 2010;9(2):181-183. PubMed
  35. Krol, E., Krejpcio, Z., Byks, H., Bogdanski, P., and Pupek-Musialik, D. Effects of chromium brewer's yeast supplementation on body mass, blood carbohydrates, and lipids and minerals in type 2 diabetic patients. Biol.Trace Elem.Res. 2011;143(2):726-737.
  36. Unisa, S., Jagannath, P., Dhir, V., Khandelwal, C., Sarangi, L., and Roy, T. K. Population-based study to estimate prevalence and determine risk factors of gallbladder diseases in the rural Gangetic basin of North India. HPB (Oxford) 2011;13(2):117-125. PubMed
  37. Noda, S., Asano, Y., and Sato, S. Lichen planus in a patient with long-term exposure to chrome. Eur.J.Dermatol. 2011;21(3):417-418. PubMed
  38. Xiang, J., Sun, Z., and Huan, J. N. Intensive chromic acid burns and acute chromium poisoning with acute renal failure. Chin Med.J.(Engl.) 7-5-2011;124(13):2071-2073.
  39. Chhabra, D., Oda, K., Jagannath, P., Utsunomiya, H., Takekoshi, S., and Nimura, Y. Chronic heavy metal exposure and gallbladder cancer risk in India, a comparative study with Japan. Asian Pac.J.Cancer Prev. 2012;13(1):187-190. PubMed
  40. Huszonek, J. Over-the-counter chromium picolinate. Am J Psychiatry 1993;150(10):1560-1561. PubMed
  41. Bunner S and McGinnis R. Chromium-induced hypoglycemia. Psychosomatics 1998;39(3):298-299. PubMed
  42. Martin, W. R. and Fuller, R. E. Suspected chromium picolinate-induced rhabdomyolysis. Pharmacotherapy 1998;18(4):860-862. DOI
  43. Proctor, D. M., Fredrick, M. M., Scott, P. K., Paustenbach, D. J., and Finley, B. L. The prevalence of chromium allergy in the United States and its implications for setting soil cleanup: a cost-effectiveness case study. Regul.Toxicol Pharmacol 1998;28(1 PubMed
  44. De Marchi S, Cecchin E, De Marchi SU. Systemic allergic dermatitis resulting from oral administration of chromium with a food supplement. Contact Dermatitis 2014;70(2):123-5. PubMed
  45. Hedberg YS, Gumulka M, Lind ML, Matura M, Lidén C. Severe occupational chromium allergy despite cement legislation. Contact Dermatitis. 2014;70(5):321-3. PubMed
  46. Thyssen JP, Jellesen MS, Møller P, Menné T, Johansen JD. Allergic chromium dermatitis from wearing 'chromium-free' footwear. Contact Dermatitis 2014;70(3):185-7. PubMed
  47. Liu Y, Cotillard A, Vatier C, et al. A Dietary Supplement Containing Cinnamon, Chromium and Carnosine Decreases Fasting Plasma Glucose and Increases Lean Mass in Overweight or Obese Pre-Diabetic Subjects: A Randomized, Placebo-Controlled Trial. PLoS One.
  48. Jamilian M, Asemi Z. Chromium Supplementation and the Effects on Metabolic Status in Women with Polycystic Ovary Syndrome: A Randomized, Double-Blind, Placebo-Controlled Trial. Ann Nutr Metab. 2015;67(1):42-8. PubMed
  49. Guimarães MM, Carvalho AC, Silva MS. Effect of chromium supplementation on the glucose homeostasis and anthropometry of type 2 diabetic patients: Double blind, randomized clinical trial: Chromium, glucose homeostasis and anthropometry. J Trace Elem Med Bi PubMed
  50. Paiva AN, Lima JG, Medeiros AC, et al. Beneficial effects of oral chromium picolinate supplementation on glycemic control in patients with type 2 diabetes: A randomized clinical study. J Trace Elem Med Biol. 2015;32:66-72. PubMed
  51. Yin RV, Phung OJ. Effect of chromium supplementation on glycated hemoglobin and fasting plasma glucose in patients with diabetes mellitus. Nutr J. 2015;14:14. PubMed
  52. Jamilian M, Zadeh Modarres S, Amiri Siavashani M, et al. The influences of chromium supplementation on glycemic control, markers of cardio-metabolic risk, and oxidative stress in infertile polycystic ovary syndrome women candidate for in vitro fertilizati
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See these in context on the Chromium monograph →

Berberine 41 references
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  2. Janbaz KH, Gilani AH. Studies on preventive and curative effects of berberine on chemical-induced hepatotoxicity in rodents. Fitoterapia 2000;71:25-33.. PubMed
  3. Wu X, Li Q, Xin H, Yu A, Zhong M. Effects of berberine on the blood concentration of cyclosporin A in renal transplanted recipients: clinical and pharmacokinetic study. Eur J Clin Pharmacol 2005;61:567-72. PubMed
  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.
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  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
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  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
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  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
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  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
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See these in context on the Berberine monograph →

Alpha-lipoic Acid 48 references
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Gymnema 12 references
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Bitter Melon 18 references
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Ceylon Cinnamon 22 references
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See these in context on the Ceylon Cinnamon monograph →

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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