Interactions on record — worth a quick check against your medications. Based on 7 of 11 ingredients. Check your meds →
Dietary supplement

Fiber Smart Ingredients & Drug Interactions

by Renew Life

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

First and foremost: checking Fiber Smart 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

Fiber Smart is a dietary supplement by Renew Life with 11 active ingredients. Its ingredients are commonly taken for constipation, diarrhea, high cholesterol.Based on those ingredients, 2,194 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Marshmallow, Dietary Fiber, Guar Gum. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Fiber Smart by Renew Life

Ask about any prescription or over-the-counter medication and we check it for interactions with Fiber Smart by Renew Life — 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 Fiber Smart by Renew Life

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 1 of its 14 active ingredients.
  • “Probiotic Blend” is a proprietary blend — the label doesn't break down how much of each component you get.
  • “Triphala” is listed as a grouped ingredient — the label doesn't break down how much of each component you get.
  • “Fiber Smart Blend” is a proprietary blend — the label gives one combined amount (3,200 mg) without saying how much of each component you get.

Fiber Smart contains 15 ingredients, including the amino acid L-glutamine, botanical extracts (fennel, slippery elm, amla, marshmallow), two live-culture probiotics (Lactobacillus acidophilus and Bifidobacterium bifidum), and fiber sources. The product also includes a proprietary blend labeled Triphala (a traditional combination of three fruits) and Fiber Smart Blend.

One ingredient, Chebulic Myrobalan, could not be checked for interactions, along with FOS, soluble fiber, insoluble fiber, B. infantis, organic flax, and the blend containers themselves. The capsule is vegetable-based.

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 wellness and sensitive digestion support.
  • We looked for evidence on: Constipation, Diarrhea, Flatulence, Antibiotic-associated diarrhea, Chemotherapy-induced diarrhea, Dyspepsia — and 4 related terms.
  • The strongest evidence on file: Black Psyllium is rated "Effective" for Constipation (Natural Medicines).
  • Also on file: Indian Gooseberry is rated "Possibly Effective" for Gastroesophageal reflux disease (GERD).
  • Also on file: Lactobacillus Acidophilus is rated "Possibly Effective" for Antibiotic-associated diarrhea.

Evidence for this product's ingredients varies widely. Amla shows some support for acid reflux (GERD) and cholesterol management.

Guar gum is possibly effective for high blood pressure, high cholesterol, irritable bowel syndrome, and constipation. L. acidophilus is possibly effective for irritable bowel syndrome, H. pylori infection, antibiotic-related diarrhea, and bacterial vaginosis.

B. bifidum is possibly effective for irritable bowel syndrome and respiratory tract infections. However, fennel, slippery elm, marshmallow, and L-glutamine all lack sufficient reliable evidence to rate their effectiveness for most conditions listed.

The data we hold does not establish this product's overall benefit for digestive health or any other specific use.

The evidence, ingredient by ingredient Black Psyllium Glutamine Fennel Slippery Elm Lactobacillus Acidophilus Marshmallow 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 8 of the 10 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 10 of 10.
  • General safety write-ups exist for 10 of 10.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most ingredients are generally well tolerated short-term. L-glutamine can cause belching, bloating, constipation, diarrhea, flatulence, nausea, and vomiting—especially at high doses.

Fennel may trigger gastrointestinal discomfort, photosensitivity, or allergic reactions; rare seizures have been reported. Amla caused epigastric discomfort in a small number of trial participants.

Guar gum commonly causes abdominal pain, bloating, diarrhea, and flatulence; rare severe blockage of the esophagus or small bowel can occur if taken without plenty of water. The probiotics can cause bloating and flatulence.

L-glutamine, amla, and marshmallow should be avoided or used only under medical supervision in pregnancy; fennel is possibly unsafe in pregnancy. Data on breastfeeding are limited for most ingredients—L-glutamine, amla, fennel, and marshmallow all have insufficient safety information during lactation.

Side effects, ingredient by ingredient Black Psyllium Glutamine Fennel Slippery Elm Lactobacillus Acidophilus Marshmallow 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?
  • 10 of the 10 matched ingredients can interact with medications — Black Psyllium, Fennel, Marshmallow, Indian Gooseberry, Lactobacillus Acidophilus, among others.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; seizure medications; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 2,195 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, check whether you're on anticonvulsants (L-glutamine may reduce their effect); blood thinners or aspirin (amla, fennel, and marshmallow all carry bleeding risk); diabetes or lithium medications (amla and marshmallow can change their levels); oral antibiotics (the probiotics may be killed, and guar gum may slow penicillin absorption); contraceptive pills or hormone replacement therapy (fennel may weaken them); ciprofloxacin or other antibiotics (fennel may lower their levels); or any regular oral medication (slippery elm and guar gum may slow absorption—separate by 30–60 minutes). These are Moderate to Minor severity interactions documented for checked ingredients.

No interactions are documented for the ingredients we could not check.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Fiber Smart may appeal to people looking for digestive support via probiotics, fiber, and traditional botanicals. If you take anticonvulsants, blood thinners, diabetes medications, lithium, birth control, or antibiotics, check your exact drugs with the tool below before starting.

Pregnant or breastfeeding? Talk with your pharmacist or doctor first, especially regarding fennel, amla, L-glutamine, and marshmallow.

Always take fiber supplements with plenty of water.

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

Assessment coverage: 10 of 14 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 25, 2018.

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 Fiber Smart, straight from the product label.

Brand Renew Life
Barcode (UPC) 631257534682
Net contents 200 Vegetable Capsule(s)
Market status On market
Date entered into DSLD Jun 25, 2018
DSLD ID 178462
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Fiber Smart by Renew Life, 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:
4 Capsule(s)
Maximum serving Sizes:
4 Capsule(s)
Servings per container
50
UPC/BARCODE
631257534682
IngredientAmount% DV
Calories15 Calorie(s)--
Total Carbohydrates2 Gram(s)1%
L-Glutamine0 NP--
Protein1 Gram(s)2%
Fennel0 NP--
Slippery Elm0 NP--
Chebulic Myrobalan0 NP--
Amla0 NP--
Belleric Myrobalan0 NP--
L. acidophilus0 NP--
B. bifidum0 NP--
FOS0 NP--
Probiotic Blend0 NP--
Dietary Fiber1 Gram(s)4%
Marshmallow0 NP--
Soluble Fiber0.25 Gram(s)--
Insoluble Fiber0.75 Gram(s)--
B. infantis0 NP--
organic Flax0 NP--
Guar Gum0 NP--
Triphala0 NP--
Fiber Smart Blend3200 mg--

Other ingredients: Vegetable Capsule

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.
General Statements

Digestive wellness, naturally

For nearly two decades, we have pioneered superior-quality digestive care supplements to help people achieve optimal health from the inside out.

Quality, purity, and potency guaranteed through expiration.

Manufactured in USA in a GMP facility.

For sensitive colons Promotes regularity Supports intestinal health

Brand IP Statement(s)

At Renew Life, we believe a healthy gut is a happy gut.

Formula

Advanced fiber for sensitive digestion Get your fiber fix and more with Fiber Smart. This high-fiber supplement is ideal for those with sensitive digestion, occasional gas, bloating, and constipation. Includes L-glutamine, probiotics, and soothing herbs to help support digestive balance and intestinal health.

Flax Probiotics L-Glutamine

This product may contain mild traces of milk proteins from fermentation ingredients.

Storage

Store in a dry place at 59-86(0)F (15-30(0)C).

Precautions

Keep out of reach of children.

Consult your healthcare professional before using this or any product if you are pregnant, nursing, trying to conceive, taking medication, or have a medical condition.

Notice: Using this supplement without at least a full glass of liquid may cause choking. Do not use this supplement if you have difficulty in swallowing, acute cough, or obstructed bowel.

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

This product may contain mild traces of milk proteins from fermentation ingredients.

General

#15629 020615 90022B

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.

Formulation

Gluten free

Free of GMOs, yeast, wheat, corn, soy, gluten, salt, fillers, binders, and artificial ingredients.

FDA Statement of Identity

Fiber Supplement

Suggested/Recommended/Usage/Directions

Directions: Take 4 capsules in the morning with 8 oz. of water. May be repeated at midday and in the evening. Drink plenty of water while using this product.

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

See for yourself

Fiber Smart by Renew Life label

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

Fiber Smart 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 Fiber Smart by Renew Life

These are the 11 active ingredients this product is made of. Select any to open its full monograph.

Serving size4 Capsule(s) Dosage formCapsule Servings per container50 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.

Protein

1 Gram(s) per serving

Dietary Fiber

Interacts with
2,025 drugs
1 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
  • › Soluble Fiber
  • › Insoluble Fiber

Fiber Smart Blend

3200 mg per serving

Other (inactive) ingredients: Vegetable Capsule. These complete the product’s ingredient list but are not active constituents.

Interaction report

Fiber Smart by Renew Life Drug Interactions

Want to check YOUR meds against Fiber Smart?

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
2,194Drugs
2,194 Moderate

Ingredients driving the most interactions

Marshmallow 2,040
Dietary Fiber 2,025
Guar Gum 2,025
Slippery Elm 2,022
Fennel 740

Individual Drug Interactions

The ingredients in Fiber Smart interact with 2,194 drugs. Click any drug to see the details.

7 of the 11 ingredients in Fiber Smart interact with drugs. Each result below shows which ingredient is responsible. Marshmallow Dietary Fiber Guar Gum Slippery Elm Fennel Probiotic Blend L-Glutamine

Each ingredient & the kinds of drugs it affects

For each ingredient in Fiber Smart 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.

Marshmallow3 drug types · 2,040 drugs

Lithium

Theoretically, due to potential diuretic effects, marshmallow might reduce excretion and increase levels of lithium.
Marshmallow is thought to have diuretic properties. To avoid lithium toxicity, the dose of lithium might need to be decreased when used with marshmallow.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, marshmallow flower might have antiplatelet effects.
Animal research suggests that marshmallow flower extract has antiplatelet effects. However, the root and leaf of marshmallow, not the flower, are the plant parts most commonly found in dietary supplements. Theoretically, use of marshmallow flower with anticoagulant/antiplatelet drugs can have additive effects, and might increase the risk for bleeding in some patients.

Likelihood Unlikely Evidence D
Oral Drugs

Theoretically, mucilage in marshmallow might impair absorption of oral drugs.
Marshmallow contains mucilage which can affect oral drug absorption. To avoid changes in absorption, take marshmallow 30-60 minutes after oral medications.

Likelihood Possible Evidence D
Marshmallow full monograph & interactions

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

Slippery Elm1 drug type · 2,022 drugs

Oral Drugs

Theoretically, slippery elm may slow the absorption and reduce serum levels of oral drugs.
Slippery elm inner bark contains mucilage, which may interfere with the absorption of orally administered drugs.

Likelihood Possible Evidence D
Slippery Elm full monograph & interactions

Fennel6 drug types · 740 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, fennel might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.

Animal research suggests that fennel oil has antithrombotic and antiplatelet effects.

Likelihood Possible Evidence D
Ciprofloxacin (Cipro)

Theoretically, fennel might decrease the levels and clinical effects of ciprofloxacin.

Animal research shows that fennel reduces ciprofloxacin bioavailability by nearly 50%, possibly due to the metal cations such as calcium, iron, and magnesium contained in fennel. This study also found that fennel increased tissue distribution and slowed elimination of ciprofloxacin.

Likelihood Probable Evidence D
Contraceptive Drugs

Theoretically, taking large amounts of fennel might decrease the effects of contraceptive drugs due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

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

Theoretically, fennel might increase levels of drugs metabolized by CYP3A4.

In vitro research suggests that fennel inhibits CYP3A4 enzyme activity. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, taking large amounts of fennel might interfere with hormone replacement therapy due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, taking large amounts of fennel might decrease the antiestrogenic effect of tamoxifen.

Some constituents of fennel have estrogenic activity, which may interfere with the antiestrogenic activity of tamoxifen.

Likelihood Possible Evidence D
Fennel full monograph & interactions

Probiotic Blend1 drug type · 182 drugs

Antibiotic Drugs

Theoretically, taking Lactobacillus acidophilus with antibiotic drugs might decrease the effectiveness of L. acidophilus.
L. acidophilus preparations usually contain live and active organisms. Therefore, simultaneously taking antibiotics might kill a significant number of the organisms. Tell patients to separate administration of antibiotics and L. acidophilus preparations by at least two hours.

Likelihood Probable Evidence D
Probiotic Blend full monograph & interactions

L-Glutamine1 drug type · 50 drugs

Anticonvulsants

Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Glutamine is metabolized to the excitatory neurotransmitter glutamate. Glutamate might have antagonistic effects with anticonvulsant drugs. However, this interaction has not yet been reported in humans.

Likelihood Possible Evidence D
L-Glutamine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Fiber Smart, from the product label.

Renew Life

Name
Renew Life Formulas
City
Palm Harbor
State
FL
ZipCode
34683
Phone Number
1-800-830-1800
Web Address
www.renewlife.com
Pharmacist Counseling Corner

Fiber Smart by Renew Life: Common Questions

Does Fiber Smart by Renew Life interact with any medications?
Yes. Based on its ingredients, Fiber Smart has a known interaction with 2,194 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Fiber Smart contains 11 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 Fiber Smart if I'm on blood thinners?
Not without checking first. Amla, fennel, and marshmallow all carry Moderate interactions with blood thinners like warfarin and clopidogrel, raising bleeding risk. Talk to your pharmacist before starting.
Will this interfere with my birth control?
Fennel may theoretically decrease how well contraceptive drugs work, though this hasn't been confirmed in humans. If you're on hormonal birth control, ask your pharmacist to review this product with your specific pill.
Should I take this if I have diabetes?
Amla can lower blood sugar and might increase the risk of low blood sugar (hypoglycemia) when combined with diabetes medications. You may need a dose adjustment. Check with your doctor before starting.
Is it safe during pregnancy?
No. Fennel, amla, and marshmallow all have insufficient safety data or are possibly unsafe in pregnancy. L-glutamine is listed as likely safe, but marshmallow is best avoided. Talk to your doctor before use.
Will this work for constipation and bloating?
Guar gum is possibly effective for constipation, and the probiotics and fiber may help. However, guar gum and the probiotics themselves commonly cause bloating and flatulence, especially at first. Start slowly and drink plenty of water.
Can I take this with antibiotics?
The probiotics (L. acidophilus and B. bifidum) may be killed by antibiotics if taken at the same time, reducing their benefit. Separate them by a few hours if possible. Also, guar gum may slow penicillin absorption—take guar gum 30–60 minutes after your antibiotic dose.

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

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

Fiber Smart label
Go deeper

The Full Monographs Behind Fiber Smart’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

Glutamine

Interacts with 50 drugs

Glutamine is the most abundant amino acid in the body and is usually made in your muscles. A prescription form is FDA-approved to help reduce sickle cell disease complications, but for most...

Read the full Glutamine monograph → Herb & supplement monograph

Fennel

Interacts with 740 drugs

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some small studies suggest possible benefit for...

Read the full Fennel monograph → Herb & supplement monograph

Slippery Elm

Interacts with 2,022 drugs

Slippery elm is a traditional herbal remedy made from the inner bark of a North American elm tree, used mainly to soothe sore throats and irritated digestive tracts. Its mucilage can coat an...

Read the full Slippery Elm monograph → Herb & supplement monograph

Lactobacillus Acidophilus

Interacts with 182 drugs

Lactobacillus acidophilus is a 'friendly' bacterium used as a probiotic to support gut and vaginal health. It is generally well tolerated in healthy people, and there is reasonable evidence...

Read the full Lactobacillus Acidophilus monograph → Herb & supplement monograph

Marshmallow

Interacts with 2,040 drugs

Marshmallow root is a traditional herb rich in soothing, gel-like fibers called mucilage, which is why it has long been used for coughs, sore throats, and stomach irritation. Evidence for th...

Read the full Marshmallow 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

Fiber Smart'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 117 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.

Glutamine 11 references
  1. Miller AL. Therapeutic considerations of L-glutamine: a review of the literature. Altern Med Rev 1999;4:239-48..
  2. Bozzetti F, Biganzoli L, Gavazzi C, et al. Glutamine supplementation in cancer patients receiving chemotherapy: a double-blind randomized study. Nutrition 1997;13:748-51.. PubMed
  3. Mebane AH. L-Glutamine and mania. Am J Psychiatry 984;141:1302-3.
  4. Meldrum BS. Glutamate as a neurotransmitter in the brain: review of physiology and pathology. J Nutr 2000;130:1007S-15S.. PubMed
  5. Garlick PJ. Assessment of the safety of glutamine and other amino acids. J Nutr 2001;131:2556S-61S.. PubMed
  6. Chapman AG. Glutamate and epilepsy. J Nutr 2000;130:1043S-5S.. PubMed
  7. Ziegler TR. Glutamine supplementation in cancer patients receiving bone marrow transplantation and high dose chemotherapy. J Nutr 2001;131:2578S-84S.. PubMed
  8. Laviano A, Molfino A, Lacaria MT, Canelli A, De Leo S, Preziosa I, Rossi Fanelli F. Glutamine supplementation favors weight loss in nondieting obese female patients. A pilot study. Eur J Clin Nutr. 2014 Nov;68(11):1264-6. PubMed
  9. Endari (l-glutamine) [package insert]. Torrance, CA: Emmaus Medical,Inc; 2017.
  10. Niihara Y, Miller ST, Kanter J, et al. A Phase 3 Trial of l-Glutamine in Sickle Cell Disease. N Engl J Med 2018;379(3):226-35. doi: 10.1056/NEJMoa1715971.
  11. Ogden HB, Child RB, Fallowfield JL, et al. Gastrointestinal Tolerance of Low, Medium and High Dose Acute Oral l-Glutamine Supplementation in Healthy Adults: A Pilot Study. Nutrients. 2020;12(10):2953. PubMed

See these in context on the Glutamine monograph →

Fennel 17 references
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  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Zhu M, Wong PY, Li RC. Effect of oral administration of fennel (Foeniculum vulgare) on ciprofloxacin absorption and disposition in the rat. J Pharm Pharmacol 1999;51:1391-6.
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  10. Tognolini, M., Barocelli, E., Ballabeni, V., Bruni, R., Bianchi, A., Chiavarini, M., and Impicciatore, M. Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. Life Sci. 2-23-2006;78(13):1419-1432. PubMed
  11. Subehan, Zaidi, S. F., Kadota, S., and Tezuka, Y. Inhibition on human liver cytochrome P450 3A4 by constituents of fennel (Foeniculum vulgare): identification and characterization of a mechanism-based inactivator. J Agric.Food Chem. 12-12-2007;55(25):101 PubMed
  12. LEVY, S. B. Bronchial asthma due to ingestion of fennel and fennel seed. Ann.Allergy 1948;6(4):415.
  13. Ottolenghi, A., De Chiara, A., Arrigoni, S., Terracciano, L., and De Amici, M. [Diagnosis of food allergy caused by fruit and vegetables in children with atopic dermatitis]. Pediatr Med Chir 1995;17(6):525-530.
  14. Trabace L, Tucci P, Ciuffreda L, et al. "Natural" relief of pregnancy-related symptoms and neonatal outcomes: above all do no harm. J Ethnopharmacol. 2015;174:396-402. PubMed
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  16. Lee HW, Ang L, Lee MS, Alimoradi Z, Kim E. Fennel for reducing pain in primary dysmenorrhea: a systematic review and meta-analysis of randomized controlled trials. Nutrients 2020;12(11):3438. PubMed
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Slippery Elm 3 references
  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Czarnecki D, Nixon R, Bekhor P, and et al. Delayed prolonged contact urticaria from the elm tree. Contact Dermatitis 1993;28:196-197. PubMed

See these in context on the Slippery Elm monograph →

Indian Gooseberry 6 references
  1. Sabu, M. C. and Kuttan, R. Anti-diabetic activity of medicinal plants and its relationship with their antioxidant property. J Ethnopharmacol. 2002;81(2):155-160. PubMed
  2. Fatima N, Pingali U, Muralidhar N. Study of pharmacodynamic interaction of Phyllanthus emblica extract with clopidogrel and ecosprin in patients with type II diabetes mellitus. Phytomedicine. 2014;21(5):579-85. PubMed
  3. Shanmugarajan D, Girish C, Harivenkatesh N, Chanaveerappa B, Prasanna Lakshmi NC. Antihypertensive and pleiotropic effects of Phyllanthus emblica extract as an add-on therapy in patients with essential hypertension-A randomized double-blind placebo-contro
  4. Akhtar MS, Ramzan A, Ali A, Ahmad M. Effect of amla fruit (Emblica officinalis Gaertn.) on blood glucose and lipid profile of normal subjects and type 2 diabetic patients. Int J Food Sci Nutr. 2011;62(6):609-16.
  5. Usharani P, Fatima N, Muralidhar N. Effects of Phyllanthus emblica extract on endothelial dysfunction and biomarkers of oxidative stress in patients with type 2 diabetes mellitus: a randomized, double-blind, controlled study. Diabetes Metab Syndr Obes. 20 PubMed
  6. Majeed M, Mundkur L, Paulose S, Nagabhushanam K. Novel Emblica officinalis extract containing ß-glucogallin vs. metformin: a randomized, open-label, comparative efficacy study in newly diagnosed type 2 diabetes mellitus patients with dyslipidemia. Food Fu

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Terminalia 9 references
  1. Sabu, M. C. and Kuttan, R. Anti-diabetic activity of medicinal plants and its relationship with their antioxidant property. J Ethnopharmacol. 2002;81(2):155-160. PubMed
  2. Rao, N. K. and Nammi, S. Antidiabetic and renoprotective effects of the chloroform extract of Terminalia chebula Retz. seeds in streptozotocin-induced diabetic rats. BMC.Complement Altern.Med 2006;6:17. PubMed
  3. Murali, Y. K., Anand, P., Tandon, V., Singh, R., Chandra, R., and Murthy, P. S. Long-term effects of Terminalia chebula Retz. on hyperglycemia and associated hyperlipidemia, tissue glycogen content and in vitro release of insulin in streptozotocin induced
  4. Senthilkumar, G. P. and Subramanian, S. Evaluation of antioxidant potential of Terminalia chebula fruits studies in streptozotocin-induced diabetic rats. Pharmaceutical Biology (Netherlands) 2007;45:511-518.
  5. Malik N, Dhawan V, Bahl A, Kaul D. Inihbitory effects of Terminalia arjuna on platelet activation in vitro in healthy subjects and patients with coronary artery disease. Platelets. 2009;20(3):183-1190.
  6. Varghese A, Savai J, Pandita N, Gaud RS. In vitro modulatory effects of Terminalia arjuna, arjunic acid, arjunetin, and arjungenin on CYP3A4, CYP2D6, and CYP2C9 enzyme activity in human liver microsomes. Toxicology Reports. 2015(2):806-16. PubMed
  7. Wu G, Dong Z, Dong J, et al. Effects of mongolian medicine Terminalia chebula Retz. on 6 CYP450 enzymes in rats. Int J Clin Exp Pathol 2020;13(12):3128-3138.
  8. Das A, Naveen J, Sreerama YN, Gnanesh Kumar BS, Baskaran V. Low-glycemic foods with wheat, barley and herbs (Terminalia chebula, Terminalia bellerica and Emblica officinalis) inhibit a-amylase, a-glucosidase and DPP-IV activity in high fat and low dose st
  9. Eltimamy M, Elshamarka M, Aboelsaad M, Sayed M, Moawad H. Effects of alcoholic extract of Terminalia Chebula dried fruit on blood biochemical profile in diabetic rats. J Diabetes Metab Disord 2022;21(1):159-170. PubMed

See these in context on the Terminalia monograph →

Lactobacillus Acidophilus 15 references
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  2. Begtrup LM, de Muckadell OB, Kjeldsen J, Christensen RD, Jarbøl DE. Long-term treatment with probiotics in primary care patients with irritable bowel syndrome--a randomised, double-blind, placebo controlled trial. Scand J Gastroenterol 2013;48(10):1127-35 PubMed
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  5. Karamali M, Dadkhah F, Sadrkhanlou M, et al. Effects of probiotic supplementation on glycaemic control and lipid profiles in gestational diabetes: a randomized, double-blind, placebo-controlled trial. Diabetes Metab 2016;42(4):234-41. PubMed
  6. Badehnoosh B, Karamali M, Zarrati M, et al. The effects of probiotic supplementation on biomarkers of inflammation, oxidative stress and pregnancy outcomes in gestational diabetes. J Matern Fetal Neonatal Med. 2018 May;31(9):1128-1136.
  7. Kumar S, Kumar R, Rohilla L, Jacob N, Yadav J, Sachdeva N. A high potency multi-strain probiotic improves glycemic control in children with new-onset type 1 diabetes mellitus: A randomized, double-blind, and placebo-controlled pilot study. Pediatr Diabete
  8. Shahriari A, Karimi E, Shahriari M, Aslani N, Khooshideh M, Arab A. The effect of probiotic supplementation on the risk of gestational diabetes mellitus among high-risk pregnant women: A parallel double-blind, randomized, placebo-controlled clinical trial PubMed
  9. Xiao SD, Zhang DZ, Lu H, et al. Multicenter, randomized, controlled trial of heat-killed Lactobacillus acidophilus LB in patients with chronic diarrhea. Adv Ther. 2003;20(5):253-60.
  10. Rossi F, Amadoro C, Gasperi M, Colavita G. Lactobacilli infection case reports in the last three years and safety implications. Nutrients. 2022;14(6):1178. PubMed
  11. Ozer M, Goksu SY, Shahverdiani A, Mustafa M. Lactobacillus acidophilus-induced endocarditis and associated splenic abscess. Case Rep Infect Dis 2020;2020:1382709.
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  13. Stoffer JN, Slingsby TJ, Giuliari GP. Lactobacillus acidophilus endophthalmitis after intravitreal bevacizumab injection requiring intraocular lens explantation. Can J Ophthalmol 2022;57(1):e21-e22. PubMed
  14. Cukovic-Cavka S, Likic R, Francetic I, Rustemovic N, Opacic M, Vucelic B. Lactobacillus acidophilus as a cause of liver abscess in a NOD2/CARD15-positive patient with Crohn's disease. Digestion 2006;73(2-3):107-10.
  15. Hui J, Ren Y, Wang Y, Han Q. Lactobacillus acidophilus endophthalmitis postcataract operation: A case report with a literature review. Ocul Immunol Inflamm 2023.

See these in context on the Lactobacillus Acidophilus monograph →

Bifidobacterium Bifidum 7 references
  1. Pierce A. The American Pharmaceutical Association Practical Guide to Natural Medicines. New York: The Stonesong Press, 1999:19.
  2. Xiao JZ, Takahashi S, Odamaki T, et al. Antibiotic susceptibility of bifidobacterial strains distributed in the Japanese market. Biosci Biotechnol Biochem. 2010;74(2):336-42. PubMed
  3. Rerksuppaphol S, Rerksuppaphol L. Randomized controlled trial of probiotics to reduce common cold in schoolchildren. Pediatr Int. 2012;54(5):682-7. PubMed
  4. Karamali M, Dadkhah F, Sadrkhanlou M, et al. Effects of probiotic supplementation on glycaemic control and lipid profiles in gestational diabetes: a randomized, double-blind, placebo-controlled trial. Diabetes Metab 2016;42(4):234-41. PubMed
  5. Badehnoosh B, Karamali M, Zarrati M, et al. The effects of probiotic supplementation on biomarkers of inflammation, oxidative stress and pregnancy outcomes in gestational diabetes. J Matern Fetal Neonatal Med. 2018 May;31(9):1128-1136.
  6. Pruccoli G, Silvestro E, Pace Napoleone C, Aidala E, Garazzino S, Scolfaro C. Are probiotics safe? Bifidobacterium bacteremia in a child with severe heart failure. Infez Med. 2019;27(2):175-178.
  7. Esaiassen E, Hjerde E, Cavanagh JP, Simonsen GS, Klingenberg C; Norwegian Study Group on Invasive Bifidobacterial Infections. Bifidobacterium bacteremia: Clinical characteristics and a genomic approach to assess pathogenicity. J Clin Microbiol. 2017;55(7) PubMed

See these in context on the Bifidobacterium Bifidum monograph →

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.
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  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 →

Marshmallow 5 references
  1. Monographs on the medicinal uses of plant drugs. Exeter, UK: European Scientific Co-op Phytother, 1997.
  2. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  3. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  4. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  5. Hage-Sleiman R, Mroueh M, Daher CF. Pharmacological evaluation of aqueous extract of Althaea officinalis flower grown in Lebanon. Pharm Biol 2011;49(3):327-33.

See these in context on the Marshmallow 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

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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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