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

Buffered Berberine 350 mg Ingredients & Drug Interactions

by Cardiovascular Research

Buffered Berberine 350 mg label
See full label image
Capsule Category: Botanical With Nutrients
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Buffered Berberine 350 mg 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

Buffered Berberine 350 mg is a dietary supplement by Cardiovascular Research with 2 active ingredients. Its ingredients are commonly taken for bone health and osteoporosis prevention, dietary calcium deficiency, heartburn relief (calcium carbonate antacids).Based on those ingredients, 1,285 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Barberry Root Extract, Calcium. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Buffered Berberine 350 mg by Cardiovascular Research

Ask about any prescription or over-the-counter medication and we check it for interactions with Buffered Berberine 350 mg by Cardiovascular Research — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Buffered Berberine 350 mg by Cardiovascular Research

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 12, 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 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains 2 active ingredients: calcium, which supports bone health and multiple metabolic functions, and barberry root extract (derived from European barberry), a traditional herbal ingredient. The product also includes inactive ingredients—gelatin, leucine, silicon dioxide, and lecithin—which are fillers and capsule components that don't add therapeutic effect.

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

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Hyperkalemia — rated "Effective" (Calcium) (Natural Medicines).
  • On file: Dyspepsia — rated "Effective" (Calcium) (Natural Medicines).
  • On file: Hypocalcemia — rated "Effective" (Calcium) (Natural Medicines).
  • On file: Kidney failure — rated "Effective" (Calcium) (Natural Medicines).
  • On file: Hyperparathyroidism — rated "Likely Effective" (Calcium) (Natural Medicines).

Calcium is effective for several conditions: it's effective for kidney failure, heartburn (dyspepsia), low blood calcium (hypocalcemia), high potassium (hyperkalemia), and likely effective for osteoporosis. Barberry root extract, however, lacks enough reliable evidence for us to rate its effectiveness.

The data we hold shows insufficient evidence for acne, bacterial vaginosis, breast cancer, dental plaque, and diabetes—so we can't tell you whether it works for those uses on the basis of what we have on file.

The evidence, ingredient by ingredient Calcium European Barberry

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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Calcium is generally well tolerated at recommended doses, though high amounts can cause problems. Common side effects taken by mouth include belching, constipation, diarrhea, gas, and stomach upset.

Rare serious concerns include kidney stones and a skin condition called calciphylaxis. There is some epidemiological concern that very high calcium intake (over 1,500–2,000 mg daily) may be associated with higher prostate cancer risk and cardiovascular disease, though the evidence is debated.

Barberry root extract carries more caution: it may be fine short-term, but solid long-term safety data is limited. One case report describes serious liver injury and blood cell problems after short-term use.

Pregnancy and breastfeeding: calcium is likely safe during pregnancy and lactation at recommended amounts, but barberry root extract is likely unsafe in both—berberine (its active component) may cross the placenta and pass into breast milk, with concerns for the baby.

Side effects, ingredient by ingredient Calcium European Barberry

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?
  • 2 of the 2 matched ingredients can interact with medications — European Barberry, Calcium.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 1,286 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, double-check with your pharmacist if you're on HIV integrase inhibitors (dolutegravir, elvitegravir), intravenous ceftriaxone, thyroid medication, heart rhythm drugs, blood thinners, blood pressure medications, diabetes drugs, sedating medications, or cyclosporine. All of these carry documented interactions with one or both ingredients.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

If you take HIV medications, thyroid pills, blood thinners, blood pressure drugs, or cyclosporine, you need to check this product with your pharmacist or doctor first—timing matters. Calcium is a familiar nutrient and generally well tolerated, but barberry root extract has limited long-term safety data and should be avoided in pregnancy and while breastfeeding.

Talk to your pharmacist before starting, especially if you're on any prescription medication.

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

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 22, 2024.

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 Buffered Berberine 350 mg, straight from the product label.

Brand Cardiovascular Research
Barcode (UPC) 696859131769
Net contents 90 Capsule(s)
Market status On market
Date entered into DSLD Mar 22, 2024
DSLD ID 304353
Product type Botanical With Nutrients
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) 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 Buffered Berberine 350 mg by Cardiovascular Research, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
90
UPC/BARCODE
696859131769
IngredientAmount% DV
Calcium36 mg2%
Barberry Root Extract350 mg--

Other ingredients: Gelatin, Leucine, Silicon Dioxide, Lecithin

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.
FDA Statement of Identity

A Dietary Supplement

Dietary Supplement

Formula

This scientifically designed supplement contains Barberry Extract (Berberis vulgaris). Calcium carbonate acts as a buffering agent.

Formulation

Liposome enhanced for maximal absorption.

Liposome Enhanced

Gluten free, Casein free

Precautions

If pregnant, nursing, or trying to conceive, do not use.

Contains: Soy

Suggested/Recommended/Usage/Directions

Directions Take one capsule daily with meals or as directed by a physician.

FDA Disclaimer Statement

This statement has 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

Buffered Berberine 350 mg by Cardiovascular Research label

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

Buffered Berberine 350 mg 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 Buffered Berberine 350 mg by Cardiovascular Research

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

Serving size1 Capsule(s) Dosage formCapsule Servings per container90 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.

Calcium

Interacts with
168 drugs
36 mg per serving Form: Calcium Carbonate

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet f...

Calcium monograph & interactions

Barberry Root Extract

Interacts with
1,210 drugs
350 mg per serving

European barberry is a shrub whose root, bark, and berries contain berberine, a bitter plant alkaloid that has been studied mostly in isolated form. S...

Barberry Root Extract monograph & interactions

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

Interaction report

Buffered Berberine 350 mg by Cardiovascular Research Drug Interactions

Want to check YOUR meds against Buffered Berberine 350 mg?

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
1,285Drugs
7 Major 1,278 Moderate

Ingredients driving the most interactions

Barberry Root Extract 1,210
Calcium 168

Individual Drug Interactions

The ingredients in Buffered Berberine 350 mg interact with 1,285 drugs. Click any drug to see the details.

2 of the 2 ingredients in Buffered Berberine 350 mg interact with drugs. Each result below shows which ingredient is responsible. Barberry Root Extract Calcium

Each ingredient & the kinds of drugs it affects

For each ingredient in Buffered Berberine 350 mg 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.

Barberry Root Extract8 drug types · 1,210 drugs

Anticholinergic Drugs

Theoretically, taking European barberry with anticholinergic drugs might cause additive effects.
In vitro evidence suggests that European barberry might have anticholinergic properties.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, European barberry may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
In vitro and animal evidence suggest that berberine, a constituent of European barberry, might inhibit platelet aggregation. Theoretically, European barberry might have a similar effect.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, taking European barberry with antidiabetes drugs might increase the risk of hypoglycemia.
Preliminary clinical evidence suggests that European barberry juice reduces fasting glucose levels in patients with type 2 diabetes who are also taking antidiabetes drugs. Additionally, some animal studies show that berberine, a constituent of European barberry, has antiglycemic potential. Monitor blood glucose levels closely.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, taking European barberry with antihypertensive drugs might increase the risk of hypotension.
Animal and human research suggests that European barberry extracts can have hypotensive effects.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, taking European barberry with cholinergic drugs might decrease the effects of cholinergic drugs.
In vitro evidence suggests that European barberry might have anticholinergic properties.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, concomitant use with drugs that have sedative properties may cause additive effects.
Animal research suggests that berberine, a constituent of European barberry, might have sedative effects. Theoretically, European barberry might have a similar effect.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, concomitant use with cyclosporine may cause additive effects.
Berberine, a constituent of European barberry, can reduce the metabolism and increase serum levels of cyclosporine. This effect is attributed to the ability of berberine to inhibit cytochrome P450 3A4 (CYP3A4), which metabolizes cyclosporine. Theoretically, European barberry might have a similar effect.

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

Theoretically, European barberry might increase the levels and clinical effects of CYP3A4 substrates.
There is very preliminary evidence suggesting that berberine, a constituent of European barberry, might inhibit the CYP3A4 enzyme. Theoretically, European barberry might have a similar effect.

Likelihood Possible Evidence D
Barberry Root Extract full monograph & interactions

Calcium18 drug types · 168 drugs

Ceftriaxone (Rocephin)

Co-administration of intravenous calcium and ceftriaxone can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys.
Avoid administering intravenous calcium in any form, such as parenteral nutrition or Lactated Ringers, within 48 hours of intravenous ceftriaxone. Case reports in neonates show that administering intravenous ceftriaxone and calcium can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys. In several cases, neonates have died as a result of this interaction. So far there are no reports in adults; however, there is still concern that this interaction might occur in adults.

Likelihood Probable Evidence D
Dolutegravir (Tivicay)

Calcium seems to reduce levels of dolutegravir.
Advise patients to take dolutegravir either 2 hours before or 6 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium carbonate 1200 mg concomitantly with dolutegravir 50 mg reduces plasma levels of dolutegravir by almost 40%. Calcium appears to decrease levels of dolutegravir through chelation.

Likelihood Probable Evidence B
Elvitegravir (Vitekta)

Calcium seems to reduce levels of elvitegravir.
Advise patients to take elvitegravir either 2 hours before or 2 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium along with elvitegravir can reduce blood levels of elvitegravir through chelation.

Likelihood Probable Evidence B
Aluminum

Calcium citrate might increase aluminum absorption and toxicity. Other types of calcium do not increase aluminum absorption.
Calcium citrate can increase the absorption of aluminum when taken with aluminum hydroxide. The increase in aluminum levels may become toxic, particularly in individuals with kidney disease. However, the effect of calcium citrate on aluminum absorption is due to the citrate anion rather than calcium cation. Calcium acetate does not appear to increase aluminum absorption.

Likelihood Possible Evidence B
Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Calcium might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and calcium can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, calcium containing products.

Likelihood Probable Evidence D
Bisphosphonates

Calcium reduces the absorption of bisphosphonates.
Advise patients to take bisphosphonates at least 30 minutes before calcium, but preferably at a different time of day. Calcium supplements decrease absorption of bisphosphonates.

Likelihood Probable Evidence C
Calcipotriene (Dovonex)

Taking calcipotriene with calcium might increase the risk for hypercalcemia.
Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriene with calcium supplements might increase the risk of hypercalcemia.

Likelihood Possible Evidence B
Digoxin (Lanoxin)

Using intravenous calcium with digoxin might increase the risk of fatal cardiac arrhythmias.
Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. However, one retrospective analysis of clinical data suggests that intravenous calcium does not increase the risk of dysrhythmias or mortality in patients receiving digoxin.

Likelihood Possible Evidence B
Diltiazem (Cardizem, Others)

Theoretically, calcium may reduce the therapeutic effects of diltiazem.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, calcium might increase this risk of hypercalcemia and reduce the effectiveness of diltiazem.

Likelihood Probable Evidence D
Levothyroxine (Synthroid, Others)

Calcium seems to reduce the absorption and effectiveness of levothyroxine.
Advise patients to take levothyroxine and calcium supplements at least 4 hours apart. Calcium reduces levothyroxine absorption, probably by forming insoluble complexes. Calcium carbonate supplements reduce effectiveness of levothyroxine in patients with hypothyroidism.

Likelihood Probable Evidence B
Lithium

Theoretically, concomitant use of calcium and lithium may increase this risk of hypercalcemia.
Clinical research suggests that long-term use of lithium may cause hypercalcemia in 10% to 60% of patients. Theoretically, concomitant use of lithium and calcium supplements may further increase this risk.

Likelihood Possible Evidence B
Quinolone Antibiotics

Calcium seems to reduce the absorption of quinolone antibiotics.
Advise patients to take oral quinolones at least 2 hours before or 4-6 hours after calcium supplements or calcium-fortified foods. Taking calcium at the same time as oral quinolones can reduce quinolone absorption. Calcium binds to quinolones in the gut.

Likelihood Probable Evidence B
Raltegravir (Isentress)

Calcium may reduce levels of raltegravir.
Pharmacokinetic research shows that taking a single dose of calcium carbonate 3000 mg along with raltegravir 400 mg twice daily modestly decreases the mean area under the curve of raltegravir, but the decrease does not necessitate a dose adjustment of raltegravir. However, a case of elevated HIV-1 RNA levels and documented resistance to raltegravir has been reported for a patient taking calcium carbonate 1 gram three times daily plus vitamin D3 (cholecalciferol) 400 IU three times daily in combination with raltegravir 400 mg twice daily for 11 months. It is thought that calcium reduced raltegravir levels by chelation, leading to treatment failure.

Likelihood Possible Evidence B
Sotalol (Betapace)

Calcium seems to reduce the absorption of sotalol.
Advise patients to separate doses by at least 2 hours before or 4-6 hours after calcium. Calcium appears to reduce the absorption of sotalol, probably by forming insoluble complexes.

Likelihood Possible Evidence B
Tetracycline Antibiotics

Calcium seems to reduce the absorption of tetracycline antibiotics.
Advise patients to take oral tetracyclines at least 2 hours before, or 4-6 hours after calcium supplements. Taking calcium at the same time as oral tetracyclines can reduce tetracycline absorption. Calcium binds to tetracyclines in the gut.

Likelihood Probable Evidence C
Thiazide Diuretics

Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Thiazides reduce calcium excretion by the kidneys. Using thiazides along with moderately large amounts of calcium carbonate increases the risk of milk-alkali syndrome (hypercalcemia, metabolic alkalosis, renal failure). Patients may need to have their serum calcium levels and/or parathyroid function monitored regularly.

Likelihood Probable Evidence C
Verapamil (Calan, Others)

Theoretically, calcium may reduce the therapeutic effects of verapamil.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, use of calcium supplements may increase this risk of hypercalcemia and reduce the effectiveness of verapamil.

Likelihood Probable Evidence D
Calcium Channel Blockers

Intravenous calcium may decrease the effects of calcium channel blockers; oral calcium is unlikely to have this effect.
Intravenous calcium is used to decrease the effects of calcium channel blockers in the management of overdose. Intravenous calcium gluconate has been used before intravenous verapamil (Isoptin) to prevent or reduce the hypotensive effects without affecting the antiarrhythmic effects. But there is no evidence that dietary or supplemental calcium when taken orally interacts with calcium channel blockers.

Likelihood Unlikely Evidence D
Calcium full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Buffered Berberine 350 mg, from the product label.

Cardiovascular Research

See all Cardiovascular Research products
Name
Cardiovascular Research, LTD.
Street Address
1061-B Shary Circle
City
Concord
State
CA
ZipCode
94518
Pharmacist Counseling Corner

Buffered Berberine 350 mg by Cardiovascular Research: Common Questions

Does Buffered Berberine 350 mg by Cardiovascular Research interact with any medications?
Yes. Based on its ingredients, Buffered Berberine 350 mg has a known interaction with 1,285 medications, including 7 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Buffered Berberine 350 mg 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 this if I'm pregnant or breastfeeding?
The calcium in this product is likely safe at recommended doses during pregnancy and breastfeeding. However, the barberry root extract is likely unsafe in both—berberine, its active ingredient, may cross the placenta and pass into breast milk with potential harm to your baby. Talk with your doctor or pharmacist about whether this product is right for you.
What are the most common side effects of this product?
From the calcium, you might experience belching, constipation, diarrhea, gas, or stomach upset. The barberry root extract's side-effect profile isn't well detailed, but one serious case of liver injury and blood cell problems has been reported. If you have any unusual symptoms—fatigue, loss of appetite, yellowing of skin or eyes, bruising, or fever—stop and contact your doctor.
Is this product safe for long-term use?
Calcium at recommended doses is generally safe long-term. Barberry root extract, however, has limited quality evidence on safe long-term use, so caution is advised if you're thinking of using it for months or years. Your pharmacist can discuss what's appropriate for your situation.
What does the barberry root extract do?
The data we hold doesn't establish reliable effectiveness for any condition. It's been studied for acne, bacterial vaginosis, breast cancer, dental plaque, and diabetes, but the evidence is insufficient to rate it. If you're considering this product for a specific reason, talk with your pharmacist about what the science actually shows.
Why do I need to separate this from certain medications?
Calcium binds to several medications in your digestive tract and reduces how much of them your body absorbs—making them less effective. That's why timing matters: taking them hours apart keeps them from interfering with each other. Your pharmacist can tell you the exact spacing needed for your specific drugs.
Is there calcium in food that would have the same interaction risk?
The data we hold focuses on supplements and medications, not food interactions, so we can't answer that from what we have. Your pharmacist or doctor can advise you on whether dietary calcium sources pose the same timing issues as this supplement.

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

Not sure if Buffered Berberine 350 mg 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.

Buffered Berberine 350 mg label
Go deeper

The Full Monographs Behind Buffered Berberine 350 mg’s Ingredients

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

Herb & supplement monograph

Calcium

Interacts with 168 drugs

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet falls short. Most people do best getting...

Read the full Calcium monograph → Herb & supplement monograph

European Barberry

Interacts with 1,210 drugs

European barberry is a shrub whose root, bark, and berries contain berberine, a bitter plant alkaloid that has been studied mostly in isolated form. Some early research on berberine is promi...

Read the full European Barberry monograph →
Sources

Sources & How We Checked

Buffered Berberine 350 mg'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 77 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.

Calcium 62 references
  1. Shils M, Olson A, Shike M. Modern Nutrition in Health and Disease. 8th ed. Philadelphia, PA: Lea and Febiger, 1994.
  2. Hernandez-Avila M, Gonzalez-Cossio T, Hernandez-Avila JE, et al. Dietary calcium supplements to lower blood lead levels in lactating women: a randomized placebo-controlled trial. Epidemiology 2003;14:206-12.. PubMed
  3. Thys-Jacobs S, Ceccarelli S, Bierman A, et al. Calcium supplementation in premenstrual syndrome: a randomized crossover trial. J Gen Intern Med 1989;4:183-9. PubMed
  4. Maton PN, Burton ME. Antacids revisited: a review of their clinical pharmacology and recommended therapeutic use. Drugs 1999;57:855-70.
  5. Clemens JD, Feinstein AR. Calcium carbonate and constipation: a historical review of medical mythopoeia. Gastroenterology 1977;72:957-61. DOI
  6. Saunders D, Sillery J, Chapman R. Effect of calcium carbonate and aluminum hydroxide on human intestinal function. Dig Dis Sci 1988;33:409-13. PubMed
  7. Friedman PA, Bushinsky DA. Diuretic effects on calcium metabolism. Semin Nephrol 1999;19:551-6.
  8. Koo WK, Walters JC, Esterlitz J, et al. Maternal calcium supplementation and fetal bone mineralization. Obstet Gynecol 1999;94:577-82. DOI
  9. Raman L, Rajalakshmi K, Krishnamachari KAVR, et al. Effect of calcium supplementation to undernourished mothers during pregnancy on the bone density of the neonates. Am J Clin Nutr 1978; 31:466-9. DOI
  10. Murry JJ, Healy MD. Drug-mineral interactions: a new responsibility for the hospital dietician. J Am Diet Assoc 1991;91:66-73.
  11. Chan JM, Giovannucci E, Andersson SO, et al. Dairy products, calcium, phosphorous, vitamin D, and risk of prostate cancer. Cancer Causes Control 1998;9:559-66.
  12. Butner LE, Fulco PP, Feldman G, et al. Calcium carbonate-induced hypothyroidism. Ann Intern Med 2000:132:595. PubMed
  13. Schneyer CR. Calcium carbonate and reduction of levothyroxine efficacy. JAMA 1998;279:750. PubMed
  14. Moser LR, Smythe MA, Tisdale JE. The use of calcium salts in the prevention and management of verapamil-induced hypotension. Ann Pharmacother 2000;34:622-9. PubMed
  15. Singh N, Singh PN, Hershman JM. Effect of calcium carbonate on the absorption of levothyroxine. JAMA 2000;283:2822-5. PubMed
  16. Kahela P, Anttila M, Tikkanen R, Sundquist H. Effect of food, food constituents and fluid volume on the bioavailability of sotalol. Acta Pharmacol Toxicol (Copenh) 1979;44:7-12.. PubMed
  17. Pletz MW, Petzold P, Allen A, et al. Effect of calcium carbonate on bioavailability of orally administered gemifloxacin. Antimicrob Agents Chemother 2003;47:2158-60.. PubMed
  18. Bar-Or D, Yoel G. Calcium and calciferol antagonize effect of verapamil in atrial fibrillation. Br Med J 1981;282:1585-6.
  19. Decktor DL, Robinson M, Maton PN, et al. Effects of aluminum/magnesium hydroxide and calcium carbonate on esophageal and gastric pH in subjects with heartburn. Am J Ther 1995;2:546-52. PubMed
  20. Simoneau G. Absence of rebound effect with calcium carbonate. Eur J Drug Metab Pharmacokinet 1996;21:351-7. PubMed
  21. Peters ML, Leonard M, Licata AA. Role of alendronate and risedronate in preventing and treating osteoporosis. Cleve Clin J Med 2001;68:945-51. PubMed
  22. Bourke JF, Mumford R, Whittaker P, et al. The effects of topical calcipotriol on systemic calcium homeostasis in patients with chronic plaque psoriasis. J Am Acad Dermatol 1997;37:929-34.
  23. Gueguen L, Pointillart A. The bioavailability of dietary calcium. J Am Coll Nutr 2000;19:119s-136s. PubMed
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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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