Interactions on record — worth a quick check against your medications. Based on 4 of 6 ingredients. Check your meds →
Dietary supplement

Herbal Bulk Ingredients & Drug Interactions

by Genestra Brands

Herbal Bulk label
See full label image
Powder Category: Botanical With Nutrients
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Herbal Bulk against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Herbal Bulk is a dietary supplement by Genestra Brands with 6 active ingredients. Its ingredients are commonly taken for constipation, diarrhea, high cholesterol.Based on those ingredients, 2,031 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Dietary Fiber, Guar Gum, Apple Pectin. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Herbal Bulk by Genestra Brands

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

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.

HelloPharmacist Scorecard of Herbal Bulk by Genestra Brands

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

Herbal Bulk is a powder containing 5 active ingredients: rice bran, oat bran, apple pectin, guar gum, and psyllium. Rice bran is a grain byproduct rich in nutrients; oat bran is soluble fiber from oats; apple pectin is a soluble fiber extracted from apples; guar gum is a thickening fiber from the guar plant; and psyllium is a soluble fiber from plantago seeds.

The product also contains two inactive ingredients, fructose and magnesium trisilicate, as excipients.

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: Digestive health and bowel regularity.
  • We looked for evidence on: Constipation, Diarrhea, Chemotherapy-induced diarrhea, Irritable bowel syndrome (IBS), Malnourishment-related diarrhea, Bowel function — and 2 related terms.
  • The strongest evidence on file: Black Psyllium is rated "Effective" for Constipation (Natural Medicines).
  • Also on file: Guar Gum is rated "Possibly Effective" for Constipation, Irritable bowel syndrome (IBS).
  • Also on file: Black Psyllium is rated "Insufficient Reliable Evidence To Rate" for Diarrhea.

Rice bran appears possibly effective for high cholesterol (dyslipidemia) but possibly ineffective for lowering colorectal cancer risk. Evidence is insufficient to rate it for alopecia areata (hair loss).

Apple pectin is possibly effective for high cholesterol and possibly effective for high blood pressure when combined with guar gum, though evidence for prediabetes and radiation exposure is insufficient to rate. Guar gum is possibly effective for high blood pressure, high cholesterol, irritable bowel syndrome, and constipation.

The evidence, ingredient by ingredient Black Psyllium Rice Bran Pectin Guar Gum

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 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Rice bran, apple pectin, and guar gum are all generally well tolerated when taken in food amounts. However, concentrated supplement doses of rice bran can cause abdominal discomfort, flatulence, and irregular bowel habits — these effects are often temporary and more likely when you first increase fiber intake.

Pectin and guar gum can cause similar digestive effects: gas, loose stools, mild cramps, and bloating. Rare allergic reactions including anaphylaxis have been reported with rice bran, pectin, and guar gum in sensitive individuals.

Guar gum must always be taken with plenty of water — taking it with too little fluid risks severe esophageal or intestinal blockage. Rice bran, pectin, and guar gum are rated likely safe or possibly safe in pregnancy and lactation at normal food amounts, though concentrated supplement safety during pregnancy and breastfeeding has not been well studied.

Side effects, ingredient by ingredient Black Psyllium Rice Bran Pectin Guar Gum

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 3 of the 4 matched ingredients can interact with medications — Black Psyllium, Pectin, Guar Gum.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: heart-rhythm medications; lithium.
  • For scale: 2,032 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check if you use digoxin (heart medication), lovastatin (cholesterol), tetracycline antibiotics, metformin (diabetes), penicillin or other antibiotics, or birth control — all carry documented Moderate or Minor interactions with apple pectin or guar gum. Additionally, because guar gum may slow absorption of many oral medications, space it 30–60 minutes away from any prescription or over-the-counter drug.

Talk with your doctor or pharmacist about your full medication list before you start.

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

Herbal Bulk is a fiber supplement that may help with cholesterol, blood pressure, and digestive regularity if you don't take medications that it might interfere with. If you take digoxin, lovastatin, tetracycline or other antibiotics, metformin, birth control, or any regular oral medication, you'll need to check with your doctor or pharmacist first — the timing and spacing of doses matter.

Start with a small amount and drink plenty of water to minimize digestive side effects and avoid blockage.

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

Assessment coverage: 4 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 23, 2023.

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 Herbal Bulk, straight from the product label.

Brand Genestra Brands
Barcode (UPC) 883196111701
Net contents 454 Gram(s); 16.01 Ounce(s)
Market status On market
Date entered into DSLD Aug 23, 2023
DSLD ID 288545
Product type Botanical With Nutrients
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Herbal Bulk by Genestra Brands, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
2 Teaspoon(s)
Maximum serving Sizes:
2 Teaspoon(s)
Servings per container
37
UPC/BARCODE
883196111701
IngredientAmount% DV
Calories5 Calorie(s)--
Total Carbohydrates10 Gram(s)4%
Dietary Fiber9 Gram(s)32%
Rice Bran2.4 Gram(s)--
Added Sugars1 Gram(s)2%
Total Sugars1 Gram(s)--
Oat Bran3 Gram(s)--
Apple Pectin600 mg--
Guar Gum600 mg--
Psyllium3.6 Gram(s)--

Other ingredients: Fructose, Magnesium Trisilicate

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.
Suggested/Recommended/Usage/Directions

Recommended Dose: Take 2 teaspoons 2 times daily or as recommended by your health professional. Mix with 8 oz of water or juice. Follow immediately with another 8 oz of water.

Precautions

Warning: If you are pregnant or lactating, have any health condition or are taking any medication, consult your health professional before use.

Keep out of the reach of children.

Use only if safety seal is intact.

May contain gluten (oat)

Storage

Store in a cool, dry place.

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.

General Statements

Packaged by weight, not volume. Settling may occur. Scan to learn about our quality excellence

FDA Statement of Identity

Dietary Supplement

Formulation

Helps promote regular bowel movements

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

See for yourself

Herbal Bulk by Genestra Brands label

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

Herbal Bulk 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 Herbal Bulk by Genestra Brands

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Teaspoon(s) Dosage formPowder Servings per container37 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.

Dietary Fiber

Interacts with
2,025 drugs
9 Gram(s) per serving

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. I...

Dietary Fiber monograph & interactions

Rice Bran

No known
interactions
2.4 Gram(s) per serving

Rice bran is the nutrient-rich outer layer of the rice grain and is a good source of fiber, healthy fats, and plant compounds. It is most studied for...

Rice Bran monograph & interactions

Oat Bran

3 Gram(s) per serving

Apple Pectin

Interacts with
23 drugs
600 mg per serving Form: Malus domestica

Pectin is a natural soluble fiber found in fruits like apples and citrus, and it is widely used in foods and as a fiber supplement. It may modestly he...

Apple Pectin monograph & interactions

Guar Gum

Interacts with
2,025 drugs
600 mg per serving

Guar gum is a soluble, gel-forming fiber from the guar bean that may modestly help with cholesterol, blood sugar, and bowel regularity. It is generall...

Guar Gum monograph & interactions

Psyllium

3.6 Gram(s) per serving

Other (inactive) ingredients: Fructose, Magnesium Trisilicate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Herbal Bulk by Genestra Brands Drug Interactions

Want to check YOUR meds against Herbal Bulk?

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
2,031Drugs
2,031 Moderate

Ingredients driving the most interactions

Dietary Fiber 2,025
Guar Gum 2,025
Apple Pectin 23

Individual Drug Interactions

The ingredients in Herbal Bulk interact with 2,031 drugs. Click any drug to see the details.

3 of the 6 ingredients in Herbal Bulk interact with drugs. Each result below shows which ingredient is responsible. Dietary Fiber Guar Gum Apple Pectin

Each ingredient & the kinds of drugs it affects

For each ingredient in Herbal Bulk 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.

Dietary Fiber7 drug types · 2,025 drugs

Carbamazepine (Tegretol)

Theoretically, black psyllium might reduce the effects of carbamazepine and increase the risk for convulsions.
Theoretically, black psyllium might reduce carbamazepine absorption. A preliminary study using blond psyllium reported decreased carbamazepine bioavailability due to binding of the drug to psyllium, as well as reduction of available fluid in the gut for dissolution of the drug. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Lithium

Theoretically, taking black psyllium at the same time as lithium might reduce lithium absorption.
The fiber in black psyllium might reduce lithium absorption and plasma levels. Some case reports describe a reduction in plasma lithium levels with concomitant administration of blond psyllium. This was reversed when psyllium was stopped. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Metformin (Glucophage)

Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Animal research shows that concurrent consumption of blond psyllium with metformin slows and increases the absorption of metformin. This interaction may also occur with black psyllium. To avoid changes in absorption, take psyllium 30-60 minutes after metformin.

Likelihood Possible Evidence D
Olanzapine (Zyprexa)

Theoretically, taking black psyllium at the same time as olanzapine might reduce olanzapine absorption.
The fiber in black psyllium might decrease the absorption of olanzapine. A single case report describes a reduction in the effectiveness of olanzapine when it was concomitantly administered with an unspecified type of psyllium 3 grams orally twice daily. This effect was reversed when psyllium was stopped.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, taking black psyllium at the same time as digoxin might reduce digoxin absorption and decrease digoxin levels.
Psyllium might bind digoxin in the gut. However, some clinical evidence suggests that psyllium does not impact digoxin absorption.

Likelihood Unlikely Evidence B
Ethinyl Estradiol

Theoretically, taking black psyllium at the same time as ethinyl estradiol might alter levels of estradiol.
Concurrent use of blond psyllium with ethinyl estradiol results in a slight increase in the extent of ethinyl estradiol absorption and a slower rate of absorption. This is unlikely to be clinically significant.

Likelihood Unlikely Evidence D
Oral Drugs

Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Psyllium seems to have variable effects on drug absorption. To avoid changes in absorption, take psyllium 30-60 minutes after oral medications. Animal research shows that blond psyllium delays and increases the absorption of metformin and ethinyl estradiol. Case reports and animal research suggest that blond psyllium might reduce absorption of lithium, digoxin, olanzapine, and carbamazepine. Finally, some pharmacokinetic studies show that psyllium does not affect the absorption of levothyroxine or warfarin. Although many of these studies evaluated blond psyllium, the fiber content in black psyllium may have similar effects.

Likelihood Possible Evidence B
Dietary Fiber full monograph & interactions

Guar Gum5 drug types · 2,025 drugs

Ethinyl Estradiol

Theoretically, guar gum might reduce the absorption of ethinyl estradiol, potentially decreasing its effectiveness.
Animal research shows that taking guar gum with ethinyl estradiol decreases ethinyl estradiol absorption. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Metformin (Glucophage)

Guar gum might reduce the absorption of metformin, potentially decreasing its effectiveness.
A small study in healthy volunteers shows that guar gum reduces the absorption rate of metformin.

Likelihood Probable Evidence B
Oral Drugs

Guar gum might reduce the absorption of some oral drugs, potentially decreasing their effectiveness.
Clinical research shows that guar gum reduces or slows absorption of medications such as penicillin and metformin. To avoid changes in absorption, take guar gum 30-60 minutes after oral medications.

Likelihood Possible Evidence B
Penicillin

Guar gum might reduce the absorption of penicillin, potentially decreasing its effectiveness.
A small clinical study in healthy volunteers shows that taking guar gum with penicillin results in decreased penicillin absorption and reduced penicillin levels.

Likelihood Probable Evidence B
Digoxin (Lanoxin)

Guar gum might slow digoxin absorption, but it does not seem to impact how much digoxin is absorbed overall.
Two small studies in healthy volunteers show no change in the overall extent of digoxin absorption, although early absorption was slowed, when taken with guar gum.

Likelihood Possible Evidence B
Guar Gum full monograph & interactions

Apple Pectin3 drug types · 23 drugs

Digoxin (Lanoxin)

Theoretically, pectin might reduce the absorption of digoxin, potentially decreasing its effectiveness.
A small clinical study shows that taking digoxin with a kaolin-pectin suspension reduces the absorption of digoxin by about 62%. It is unclear if these effects are due to pectin, kaolin, or the combination.

Likelihood Possible Evidence B
Lovastatin (Mevacor)

Theoretically, pectin might reduce the absorption of lovastatin, potentially decreasing its effectiveness.
Case reports suggest that concomitant use of pectin and lovastatin might reduce the cholesterol-lowering effect of lovastatin, possibly due to reduced intestinal absorption of lovastatin.

Likelihood Possible Evidence D
Tetracycline Antibiotics

Theoretically, pectin might reduce the absorption of tetracycline antibiotics, potentially decreasing their effectiveness.
A small clinical study shows that taking tetracycline with bismuth subsalicylate in a kaolin-pectin suspension reduces the absorption of tetracycline by about 34%. It is unclear if these effects are due to pectin, kaolin, bismuth subsalicylate, or the combination.

Likelihood Possible Evidence B
Apple Pectin full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Herbal Bulk, from the product label.

Genestra Brands

Name
Seroyal USA
City
Pittsburgh
State
PA
ZipCode
15275
Phone Number
1-888-737-6925
Web Address
seroyal.com
Pharmacist Counseling Corner

Herbal Bulk by Genestra Brands: Common Questions

Does Herbal Bulk by Genestra Brands interact with any medications?
Yes. Based on its ingredients, Herbal Bulk has a known interaction with 2,031 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Herbal Bulk contains 6 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?
Rice bran is rated likely safe during pregnancy and lactation. Apple pectin and guar gum are rated likely safe or possibly safe at typical food amounts, but concentrated supplement safety during pregnancy and breastfeeding has not been well studied — discuss this with your doctor or pharmacist before using the product at full dose.
What digestive side effects might I notice?
Starting out, you may experience bloating, gas, flatulence, loose stools, abdominal cramping, or mild discomfort — these are common when you increase fiber intake and usually fade over time. Start with a small amount and drink plenty of water. Rare allergic reactions like hives or swelling have been reported in sensitive people.
Why does this product need to be taken with plenty of water?
Guar gum and psyllium are soluble fibers that absorb water and swell; without enough fluid, they can form a blockage in your throat or intestines. Always take this powder with at least one full glass of water.
Will this help my cholesterol or blood pressure?
Rice bran, apple pectin, and guar gum are all possibly effective for high cholesterol, and guar gum is possibly effective for high blood pressure. That said, the evidence isn't definitive — talk with your doctor about whether this supplement fits into your overall plan.
Is there any reason to space this out from my medications?
Yes — guar gum and apple pectin can reduce how well your body absorbs certain drugs. If you take any regular oral medication, ask your doctor or pharmacist; you may need to take this product at least 30–60 minutes away from your prescriptions.

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

Not sure if Herbal Bulk is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.

Herbal Bulk label
Go deeper

The Full Monographs Behind Herbal Bulk’s Ingredients

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

Herb & supplement monograph

Black Psyllium

Interacts with 2,025 drugs

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. It is best known and most studied for rel...

Read the full Black Psyllium monograph → Herb & supplement monograph

Rice Bran

Rice bran is the nutrient-rich outer layer of the rice grain and is a good source of fiber, healthy fats, and plant compounds. It is most studied for helping lower cholesterol, but for most...

Read the full Rice Bran monograph → Herb & supplement monograph

Pectin

Interacts with 23 drugs

Pectin is a natural soluble fiber found in fruits like apples and citrus, and it is widely used in foods and as a fiber supplement. It may modestly help with cholesterol, blood sugar, and di...

Read the full Pectin monograph → Herb & supplement monograph

Guar Gum

Interacts with 2,025 drugs

Guar gum is a soluble, gel-forming fiber from the guar bean that may modestly help with cholesterol, blood sugar, and bowel regularity. It is generally safe in food amounts, but concentrated...

Read the full Guar Gum monograph →
Sources

Sources & How We Checked

Herbal Bulk'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 62 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.

Black Psyllium 18 references
  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
  4. Etman M. Effect of a bulk forming laxative on the bioavailablility of carbamazepine in man. Drug Dev Ind Pharm 1995;21:1901-6.
  5. Perlman BB. Interaction between lithium salts and ispaghula husk. Lancet 1990;335:416.
  6. Vaswani SK, Hamilton RG, Valentine MD, Adkinson NF. Psyllium laxative-induced anaphylaxis, asthma, and rhinitis. Allergy 1996;51:266-8. PubMed
  7. Lantner RR, Espiritu BR, Zumerchik P, Tobin MC. Anaphylaxis following ingestion of a psyllium-containing cereal. JAMA 1990;264:2534-6. DOI
  8. Kaplan MJ. Anaphylactic reaction to "Heartwise." N Engl J Med 1990;323:1072-3. DOI
  9. Nordstrom M, Melander A, Robertsson E, Steen B. Influence of wheat bran and of a bulk-forming ispaghula cathartic on the bioavailability of digoxin in geriatric in-patients. Drug Nutr Interact 1987;5:67-9..
  10. Robinson DS, Benjamin DM, McCormack JJ. Interaction of warfarin and nonsystemic gastrointestinal drugs. Clin Pharmacol Ther 1971;12:491-5. PubMed
  11. Garcia JJ, Fernandez N, Diez MJ, et al. Influence of two dietary fibers in the oral bioavailability and other pharmacokinetic parameters of ethinyloestradiol. Contraception 2000;62:253-7. PubMed
  12. Fernandez N, Lopez C, Díez R, et al. Drug interactions with the dietary fiber Plantago ovata husk. Expert Opin Drug Metab Toxicol 2012;8(11):1377-86.
  13. Semen plantaginis in: WHO Monographs on Selected Medicinal Plants, volume 1. World Health Organization, Geneva, 1999. Available at http://apps.who.int/medicinedocs/en/d/Js2200e/. Accessed November 26, 1026.
  14. Code of Federal Regulations, Title 21 (21CFR 101.17). Food labeling warning, notice, and safe handling statements. Available at www.ecfr.gov/cgi-bin/text-idx?SID=20f647d3b74161501f46564b915b4048&mc=true&node=se21.2.101_117&rgn=div8. Accessed December 3, 2
  15. Code of Federal Regulations, Title 21 (21CFR 201.319). Specific labeling requirements - water-soluble gums, hydrophilic gums, and hydrophilic mucilloids. Available at www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=201.319. Accessed Dece
  16. Diez R, Garcia JJ, Diez MJ, Sierra M, Sahagun AM, Fernandez N. Influence of Plantago ovata husk (dietary fiber) on the bioavailability and other pharmacokinetic parameters of metformin in diabetic rabbits. BMC Complement Altern Med. 2017 Jun 7;17(1):298. PubMed
  17. Chiu AC, Sherman SI. Effects of pharmacological fiber supplements on levothyroxine absorption. Thyroid. 1998;8(8):667-71. PubMed
  18. Merrick C, Madden CA, Capurso NA. A Case of Blunted Orally Disintegrating Olanzapine Effect Due to Coadministered Psyllium. J Clin Psychiatry 2021;82(2):20cr13633. PubMed

See these in context on the Black Psyllium monograph →

Rice Bran 7 references
  1. Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
  2. Fujiwaki T, Furusho K. The effects of rice bran broth bathing in patients with atopic dermatitis. Acta Paediatr Jpn 1992;34:505-10.
  3. Uenotsuchi T, Satoh E, Kiryu H, Yano Y. Pyemotes dermatitis caused by indirect contact with husk rice. Br J Dermatol 2000;143:680-2. DOI
  4. Satoh R, Tsuge I, Tokuda R, Teshima R. Analysis of the distribution of rice allergens in brown rice grains and of the allergenicity of products containing rice bran. Food Chem. 2019;276:761-767. PubMed
  5. Togashi Y, Inomata N, Suzuki A, Hakuta A, Aihara M. Pediatric case with rice bran allergy induced by epicutaneous sensitization in a family rice shop. Allergol Int. 2019;68(1):117-118. PubMed
  6. So WKW, Chan JYW, Law BMH, et al. Effects of a Rice Bran Dietary Intervention on the Composition of the Intestinal Microbiota of Adults with a High Risk of Colorectal Cancer: A Pilot Randomised-Controlled Trial. Nutrients 2021;13(2):526. PubMed
  7. Haneda Y, Kadowaki S, Furui M, Taketani T. A pediatric case of food-dependent exercise-induced anaphylaxis due to rice bran. Asia Pac Allergy 2021;11(1):e4. PubMed

See these in context on the Rice Bran monograph →

Pectin 11 references
  1. Jaakkola MS, et al. Asthma caused by occupational exposure to pectin. J Allergy Clin Immunol 1997;100:575-6. PubMed
  2. Westphal W, et al. [Exogenous allergic asthma following pectin exposure-a new occupational allergen]. Pneumologie 1990;44(Suppl 1):337-8.
  3. Baldwin JL, et al. Pectin-induced occupational asthma. Chest 1993;104:1936-7. PubMed
  4. Cohen AJ, Forse MS, Tarlo SM. Occupational asthma caused by pectin inhalation during the manufacture of jam. Chest 1993;103:309-11.
  5. Kraut A, et al. Christmas candy maker's asthma. IgG4-mediated pectin allergy. Chest 1992;102:1605-7. PubMed
  6. Richter WO, Jacob BG, Schwandt P. Interaction between fibre and lovastatin. Lancet 1991;338:706.
  7. Albert KS, Ayres JW, DiSanto AR, et al. Influence of kaolin-pectin suspension on digoxin bioavailability. J Pharm Sci 1978;67:1582-6. PubMed
  8. Albert KS, Welch RD, DeSante KA, et al. Decreased tetracycline bioavailability caused by a bismuth subsalicylate antidiarrheal mixture. J Pharm Sci 1979;68:586-8. PubMed
  9. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  10. Federal Register April 17,2003. Anti-Diarrheal Products for over-the-counter human use; final monograph. Available at: http://www.fda.gov/OHRMS/DOCKETS/98fr/03-9380.pdf (Accessed 27 December 2004).
  11. Washio K, Nakamura M, Sato N, et al. Anaphylaxis in a pectin- and cashew nut-allergic child caused by a citrus bath. Allergol Int 2022;71(1):155-157. PubMed

See these in context on the Pectin monograph →

Guar Gum 26 references
  1. Gin H, Orgerie MB, Aubertin J. The influence of Guar gum on absorption of metformin from the gut in healthy volunteers. Horm Metab Res 1989;21:81-3.
  2. Huupponen R, Seppala P, Iisalo E. Effect of guar gum, a fibre preparation, on digoxin and penicillin absorption in man. Eur J Clin Pharmacol 1984;26:279-81. PubMed
  3. Malo JL, Cartier A, L'Archeveque J, et al. Prevalence of occupational asthma and immunologic sensitization to guar gum among employees at a carpet-manufacturing plant. J Allergy Clin Immunol 1990;86:562-9. PubMed
  4. Lagier F, Cartier A, Somer J, et al. Occupational asthma caused by guar gum. J Allergy Clin Immunol 1990;85:785-90.
  5. Lewis JH. Esophageal and small bowel obstruction from guar gum-containing diet pills: analysis of 26 cases reported to the FDA. Am J Gastroenterol 1992;87:1424-8.
  6. Vuorinen-Markkola H, Sinisalo M, Koivisto VA. Guar gum in insulin-dependent diabetes: effects on glycemic control and serum lipoproteins. Am J Clin Nutr 1992;56:1056-1060. PubMed
  7. Superko HR, Haskell WL, Sawrey-Kubicek L, Farquhar JW. Effects of solid and liquid guar gum on plasma cholesterol and triglyceride concentrations in moderate hypercholesterolemia. Am J Cardiol 1988;62:51-5. PubMed
  8. Garcia JJ, Fernandez N, Diez MJ, et al. Influence of two dietary fibers in the oral bioavailability and other pharmacokinetic parameters of ethinyloestradiol. Contraception 2000;62:253-7. PubMed
  9. Groop PH, Aro A, Stenman S, Groop L. Long-term effects of guar gum in subjects with non-insulin-dependent diabetes mellitus. Am J Clin Nutr 1993;58:513-8. PubMed
  10. Chuang LM, Jou TS, Yang WS, et al. Therapeutic effect of guar gum in patients with non-insulin-dependent diabetes mellitus. J Formos Med Assoc 1992;91:15-9.
  11. Ebeling P, Yki-Jarvinen H, Aro A, et al. Glucose and lipid metabolism and insulin sensitivity in type 1 diabetes: the effect of guar gum. Am J Clin Nutr 1988;48:98-103. PubMed
  12. Scheen AJ. Clinical pharmacokinetics of metformin. Clin Pharmacokinet 1996;30:359-71. PubMed
  13. Knopp RH, Superko HR, Davidson M, et al. Long-term blood cholesterol-lowering effects of a dietary fiber supplement. Am J Prev Med 1999;17:18-23. PubMed
  14. Patrick PG, Gohman SM, Marx SC, et al. Effect of supplements of partially hydrolyzed guar gum on the occurrence of constipation and use of laxative agents. J Am Diet Assoc 1998;98:912-4. PubMed
  15. Osterlund P, Ruotsalainen T, Korpela R, et al. Lactobacillus supplementation for diarrhoea related to chemotherapy of colorectal cancer: a randomised study. Br J Cancer 2007;97:1028-34. PubMed
  16. Lembcke B, Hasler K, Kramer P, et al. Plasma digoxin concentrations during administration of dietary fibre (guar gum) in man. Z Gastroenterol 1982;20;164-7.
  17. Riikonen, S., Savonius, H., Gylling, H., Nikkila, K., Tuomi, A. M., and Miettinen, T. A. Oral guar gum, a gel-forming dietary fiber relieves pruritus in intrahepatic cholestasis of pregnancy. Acta Obstet.Gynecol.Scand. 2000;79(4):260-264. DOI
  18. Kovacs, E. M., Westerterp-Plantenga, M. S., Saris, W. H., Goossens, I., Geurten, P., and Brouns, F. The effect of addition of modified guar gum to a low-energy semisolid meal on appetite and body weight loss. Int.J.Obes.Relat Metab Disord. 2001;25(3):307 PubMed
  19. Halama, W. H. and Mauldin, J. L. Distal esophageal obstruction due to a guar gum preparation (Cal-Ban 3000). South.Med.J. 1992;85(6):642-645. PubMed
  20. Landin, K., Holm, G., Tengborn, L., and Smith, U. Guar gum improves insulin sensitivity, blood lipids, blood pressure, and fibrinolysis in healthy men. Am.J.Clin.Nutr. 1992;56(6):1061-1065. PubMed
  21. Cicero, A. F., Derosa, G., Manca, M., Bove, M., Borghi, C., and Gaddi, A. V. Different effect of psyllium and guar dietary supplementation on blood pressure control in hypertensive overweight patients: a six-month, randomized clinical trial. Clin.Exp.Hyp PubMed
  22. Simons LA, Gayst S, Balasubramaniam S, Ruys J. Long-term treatment of hypercholesterolaemia with a new palatable formulation of guar gum. Atherosclerosis 1982;45:101-108. PubMed
  23. Salenius JP, Harju E, Jokela H, et al. Long term effects of guar gum on lipid metabolism after carotid endarterectomy. BMJ 1-14-1995;310:95-96. PubMed
  24. Gylling, H., Riikonen, S., Nikkila, K., Savonius, H., and Miettinen, T. A. Oral guar gum treatment of intrahepatic cholestasis and pruritus in pregnant women: effects on serum cholestanol and other non-cholesterol sterols. Eur.J.Clin.Invest 1998;28(5):35 PubMed
  25. Brillantino A, Iacobellis F, Izzo G, et al. Maintenance therapy with partially hydrolyzed guar gum in the conservative treatment of chronic anal fissure: results of a prospective, randomized study. Biomed Res Int 2014;2014:964942. PubMed
  26. Polymeros D, Beintaris I, Gaglia A, et al. Partially hydrolyzed guar gum accelerates colonic transit time and improves symptoms in adults with chronic constipation. Dig Dis Sci 2014;59(9):2207-14. PubMed

See these in context on the Guar Gum monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

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

© 2021 Therapeutic Research Center, LLC

Keep exploring
Supplement interaction checker › Check any supplement or product against your medications Drug–drug interactions › Check two or more of your medications against each other Browse medications A–Z › Every drug we've checked against herbs & supplements NDC & pricing lookup › Find a drug’s NDCs, packaging and costs Ask a pharmacist › Free, personal answer from our licensed team