Barley Grass Ingredients & Drug Interactions
by Nature's Way
What is this page for?
First and foremost: checking Barley Grass 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
Barley Grass is a dietary supplement by Nature's Way with 2 active ingredients. Its ingredients are commonly taken for constipation, diarrhea, high cholesterol.Based on those ingredients, 2,025 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Dietary Fiber, Barley. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Barley Grass by Nature's Way
Ask about any prescription or over-the-counter medication and we check it for interactions with Barley Grass by Nature's Way — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Barley Grass by Nature's Way
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.
What’s inside
Full disclosure
This product contains one active ingredient: barley. Barley grass is the young green shoot of the barley plant, traditionally used as a nutritional supplement.
Does it work?
Strong evidence
Barley is rated Likely Effective for lowering cholesterol (hypercholesterolemia) and supporting heart health in coronary heart disease. The evidence supporting these uses is solid.
Beyond those two areas, effectiveness data isn't established in what we hold.
How safe is it?
Well-documented data
Barley is generally well tolerated when taken by mouth. The most common side effects are mild digestive ones — bloating, gas, abdominal distension, and an unpleasant taste.
Because barley contains gluten, it's not suitable if you have celiac disease or gluten sensitivity. Some people may have allergic reactions, ranging from mild tingling around the mouth and lips to more serious symptoms like swelling, hives, chest tightness, shortness of breath, or in rare cases anaphylaxis.
Concentrated barley supplements haven't been well studied in pregnancy or while breastfeeding — the safety data we hold is limited for those situations. Talk with your doctor or pharmacist if you're pregnant, planning to become pregnant, or nursing.
Meds to double-check
Moderate interaction found
If you take triclabendazole (Egaten), a parasite medication, let your pharmacist know before starting this product — barley may reduce how well it works. No other medication interactions are documented for the ingredients we could check.
The bottom line
Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.
Barley Grass is a solid choice if you're looking to support cholesterol and heart health and aren't gluten-sensitive. If you take triclabendazole for a parasitic infection, check with your pharmacist first — barley may interfere with it.
Anyone with a gluten sensitivity or allergy should avoid this product.
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 Jan 22, 2022.
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
General information
Key facts about Barley Grass, straight from the product label.
| Brand | Nature's Way |
|---|---|
| Barcode (UPC) | 033674102503 |
| Net contents | 100 Vegan Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Jan 22, 2022 |
| DSLD ID | 259304 |
| Product type | Botanical |
| Supplement form | Capsule |
| Dietary claims / uses | All Other |
| Intended target group(s) | Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free |
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 Barley Grass by Nature's Way, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Calories | 5 Calorie(s) | -- |
| Total Carbohydrates | 1 Gram(s) | 1% |
| Dietary Fiber | 1 Gram(s) | 2% |
| Barley | 1.5 Gram(s) | -- |
Other ingredients: Hypromellose
Tap any ingredient to jump to its full detail below.
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.
Formulation
Super food At Nature's Way, we believe in quality you can trust. So, we start by sourcing botanicals from the places they grow best. Then we use three distinct levels of scientific testing methods to ensure ingredients meet our uncompromising standards. Look for the Tru-ID logo to find products certified for authenticity by independent, third-party testing.
Young harvest
Non GMO Project Verified - nongmoproject.org
Gluten free. No sugar, salt, yeast, wheat, soy, corn, dairy products, or artificial colors, flavors, or preservatives.
Vegan
Brand IP Statement(s)
Nature's Way Since 1969
Copyright 2019 Nature's Way Brands, LLC
Seals/Symbols
Certified Authentic - Tru-ID Non GMO Project Verified - nongmoproject.org
Quality Global Sourcing - Bottled & Tested in the USA
FDA Statement of Identity
Dietary Supplement
Suggested/Recommended/Usage/Directions
Recommendation: Take 3 capsules three times daily.
Precautions
If pregnant, nursing, or taking any medications, consult a healthcare professional before use.
Keep out of reach of children.
Safety sealed with printed inner seal. Do not use if seal is broken or missing.
General Statements
Bottles made from 97% post-consumer recycled plastic
Formula
Barley Grass 1,500 mg per serving
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Barley Grass by Nature's Way label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Barley Grass by Nature's Way
These are the 2 active ingredients this product is made of. Select any to open its full monograph.
Serving size3 Vegan Capsule(s) Dosage formCapsule Servings per container33 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 with2,025 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. I...
Dietary Fiber monograph & interactionsBarley
Interacts with1 drug
Barley is a nutritious whole grain that is a good source of soluble fiber called beta-glucan, which has solid evidence for modestly lowering LDL ('bad...
Barley monograph & interactionsOther (inactive) ingredients: Hypromellose. These complete the product’s ingredient list but are not active constituents.
Barley Grass by Nature's Way Drug Interactions
HelloPharmacist Interaction Report
Barley Grass by Nature's Way has one documented interaction we need to flag.
Barley may reduce how well triclabendazole (Egaten), a medication for certain parasitic infections, works in your body. Animal studies suggest barley can lower the amount of triclabendazole your system absorbs when you take them together, though this hasn't been proven in humans yet — it's a Moderate concern.
Read the full breakdown — every affected drug type, severity by severity
No other medication interactions are documented for barley in our data. That said, absence of documented interactions isn't a guarantee none exist.
If you take triclabendazole or any other prescription medication, run them through the interaction checker on this page before you start.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Barley Grass?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Barley Grass interact with 2,025 drugs. Click any drug to see the details.
2 of the 2 ingredients in Barley Grass interact with drugs. Each result below shows which ingredient is responsible. Dietary Fiber Barley
Alogliptin, MetforminKazano
How Alogliptin, Metformin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Alogliptin, Metformin interactionCanagliflozin, MetforminInvokamet
How Canagliflozin, Metformin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Canagliflozin, Metformin interactionCanagliflozin, Metformin HydrochlorideInvokamet XR
How Canagliflozin, Metformin Hydrochloride interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Canagliflozin, Metformin Hydrochloride interactionCarbamazepineCarbatrol, Carnexiv, Equetro, Tegretol, Tegretol XR
How Carbamazepine interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Carbamazepine (tegretol) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Carbamazepine interactionDapagliflozin Propanediol, MetforminXigduo XR
How Dapagliflozin Propanediol, Metformin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Dapagliflozin Propanediol, Metformin interactionDapagliflozin, Metformin Hydrochloride, Saxagliptin HydrochlorideQternmet XR
How Dapagliflozin, Metformin Hydrochloride, Saxagliptin Hydrochloride interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Dapagliflozin, Metformin Hydrochloride, Saxagliptin Hydrochloride interactionEmpagliflozin, Linagliptin, Metformin HydrochlorideTrijardy XR
How Empagliflozin, Linagliptin, Metformin Hydrochloride interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Empagliflozin, Linagliptin, Metformin Hydrochloride interactionEmpagliflozin, MetforminSynjardy
How Empagliflozin, Metformin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Empagliflozin, Metformin interactionEmpagliflozin, Metformin HydrochlorideSynjardy XR
How Empagliflozin, Metformin Hydrochloride interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Empagliflozin, Metformin Hydrochloride interactionErtugliflozin, Metformin HydrochlorideSegluromet
How Ertugliflozin, Metformin Hydrochloride interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Ertugliflozin, Metformin Hydrochloride interactionGlipizide, MetforminMetaglip
How Glipizide, Metformin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Glipizide, Metformin interactionGlyburide, MetforminGlucovance
How Glyburide, Metformin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Glyburide, Metformin interactionLinagliptin, Metformin HydrochlorideJentadueto XR
How Linagliptin, Metformin Hydrochloride interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Linagliptin, Metformin Hydrochloride interactionLithium Carbonate (prescription Drug)Eskalith, Lithium Carbonate
How Lithium Carbonate (prescription Drug) interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Lithium Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Lithium Carbonate (prescription Drug) interactionMetforminGlucophage, Metformin
How Metformin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Metformin interactionMetformin HydrochlorideRiomet ER
How Metformin Hydrochloride interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Metformin Hydrochloride interactionMetformin, LinagliptinJentadueto
How Metformin, Linagliptin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Metformin, Linagliptin interactionMetformin, RosiglitazoneAvandamet
How Metformin, Rosiglitazone interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Metformin, Rosiglitazone interactionMetformin, SitagliptinJanumet, Janumet XR
How Metformin, Sitagliptin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Metformin, Sitagliptin interactionOlanzapineZyprexa
How Olanzapine interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Olanzapine (zyprexa) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Olanzapine interactionSaxagliptin, Metformin XrKombiglyze
How Saxagliptin, Metformin Xr interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Saxagliptin, Metformin Xr interactionSitagliptin, MetforminZituvimet
How Sitagliptin, Metformin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Sitagliptin, Metformin interactionTriclabendazoleEgaten
How Triclabendazole interacts with Barley Grass — through 2 ingredients. Tap an ingredient for the detail:
BarleyTriclabendazole (egaten) Moderate
Interaction Summary
Theoretically, barley might decrease the clinical effects of triclabendazole.
Read the full Barley + Triclabendazole interactionDietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Triclabendazole interactionPioglitazone, MetforminActoPlus Met
How Pioglitazone, Metformin interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Pioglitazone, Metformin interaction"phentolamineOraVerse, Rogitine, Ryzumvi
How "phentolamine interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + "phentolamine interaction6-mercaptopurinePurinethol
How 6-mercaptopurine interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + 6-mercaptopurine interactionAbacavirZiagen
How Abacavir interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Abacavir interactionAbacavir Sulfate, Dolutegravir, LamivudineTriumeq
How Abacavir Sulfate, Dolutegravir, Lamivudine interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Abacavir Sulfate, Dolutegravir, Lamivudine interactionAbacavir, LamivudineEpzicom
How Abacavir, Lamivudine interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Abacavir, Lamivudine interactionAbciximabReoPro
How Abciximab interacts with Barley Grass — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Abciximab interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Barley Grass 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 Fiber
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.
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.
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.
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.
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.
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.
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.
Barley
Triclabendazole (Egaten)
Theoretically, barley might decrease the clinical effects of triclabendazole.
Animal research suggests that a diet supplemented with barley can reduce the bioavailability of triclabendazole when taken concomitantly. This effect has not been shown in humans.
Brand information
Manufacturer and brand details for Barley Grass, from the product label.
Nature's Way
See all Nature's Way products- Name
- Nature's Way Brands, LLC
- City
- Green Bay
- State
- WI
- ZipCode
- 54311
- Phone Number
- 1-800-962-8873
- Web Address
- naturesway.com
Barley Grass by Nature's Way: Common Questions
Does Barley Grass by Nature's Way interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
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Can I take this if I'm pregnant or breastfeeding?
What are the most common side effects?
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Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Barley Grass is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind Barley Grass’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Black Psyllium
Interacts with 2,025 drugsBlack 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 monographBarley
Interacts with 1 drugBarley is a nutritious whole grain that is a good source of soluble fiber called beta-glucan, which has solid evidence for modestly lowering LDL ('bad') cholesterol when eaten regularly. It...
Read the full Barley monograph →Sources & How We Checked
Barley Grass'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 33 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
- McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
- Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
- Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
- Etman M. Effect of a bulk forming laxative on the bioavailablility of carbamazepine in man. Drug Dev Ind Pharm 1995;21:1901-6.
- Perlman BB. Interaction between lithium salts and ispaghula husk. Lancet 1990;335:416.
- Vaswani SK, Hamilton RG, Valentine MD, Adkinson NF. Psyllium laxative-induced anaphylaxis, asthma, and rhinitis. Allergy 1996;51:266-8. PubMed
- Lantner RR, Espiritu BR, Zumerchik P, Tobin MC. Anaphylaxis following ingestion of a psyllium-containing cereal. JAMA 1990;264:2534-6. DOI
- Kaplan MJ. Anaphylactic reaction to "Heartwise." N Engl J Med 1990;323:1072-3. DOI
- 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..
- Robinson DS, Benjamin DM, McCormack JJ. Interaction of warfarin and nonsystemic gastrointestinal drugs. Clin Pharmacol Ther 1971;12:491-5. PubMed
- 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
- 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.
- 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.
- 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
- 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
- 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
- Chiu AC, Sherman SI. Effects of pharmacological fiber supplements on levothyroxine absorption. Thyroid. 1998;8(8):667-71. PubMed
- 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
Barley 15 references
- Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
- Fernandez-Anaya S, Crespo JF, Rodriguez JR, et al. Beer anaphylaxis. J Allergy Clin Immunol 1999;103:959-60.
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- Ferre, I., Giraldez, F. J., Alvarez-Bujidos, M. L., and Mantecon, A. R. Influence of barley supplement on plasma concentration of triclabendazole metabolites in sheep. Vet.Rec. 11-22-1997;141(21):549-551. PubMed
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