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

Herbal CA Ingredients & Drug Interactions

by Nature's Sunshine

Capsule Category: Botanical
Most serious interaction: Major
The interaction bottom line Most serious interaction: Major

Herbal CA is a dietary supplement by Nature's Sunshine with 7 active ingredients. Its ingredients are commonly taken for high cholesterol, digestive complaints, menopausal symptoms.Based on those ingredients, 2,222 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Marshmallow, Plantain, Hops. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Herbal CA by Nature's Sunshine

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

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 0 of its 7 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (385 mg) without saying how much of each component you get.

Herbal CA contains seven active ingredients in a proprietary blend: alfalfa, horsetail, oat straw extract, marshmallow, plantain (black psyllium), wheat grass, and hops. Each brings different traditional uses — alfalfa and plantain are used for digestive support and general wellness, oat straw for cardiovascular health, marshmallow for soothing irritated tissues, horsetail for mineral content, wheat grass for nutritional value, and hops for relaxation.

The capsule itself is an inactive ingredient.

Does it work?

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

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

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Constipation — rated "Effective" (Black Psyllium) (Natural Medicines).
  • On file: Coronary heart disease (CHD) — rated "Likely Effective" (Black Psyllium) (Natural Medicines).
  • On file: Dyslipidemia — rated "Likely Effective" (Oats) (Natural Medicines).
  • On file: Diabetes — rated "Possibly Effective" (Oats) (Natural Medicines).
  • On file: Gastric cancer — rated "Possibly Effective" (Oats) (Natural Medicines).

According to the evidence we hold, oat straw extract is likely effective for high cholesterol (dyslipidemia) and heart disease risk. Plantain is effective for constipation and likely effective for heart disease risk.

For the other active ingredients — alfalfa, horsetail, marshmallow, wheat grass, and hops — the evidence is insufficient to establish whether they work for their traditional uses. This means research hasn't yet confirmed benefits for those claims, not that they don't work.

The evidence, ingredient by ingredient Alfalfa Horsetail Oats Marshmallow Black Psyllium Couch Grass Hops

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 5 of the 7 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 7 of 7.
  • General safety write-ups exist for 7 of 7.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Alfalfa is generally well tolerated when eaten as food in small amounts, though supplements carry more risk. It should be avoided during pregnancy due to its estrogen-like activity and avoided while breastfeeding due to insufficient safety data.

Common side effects include stomach discomfort, diarrhea, and gas; rarely, a lupus-like syndrome has been reported with long-term use. Horsetail may cause bloating, increased bowel movements, and nausea, and should be avoided in pregnancy and breastfeeding.

Crude horsetail contains thiaminase, which can cause vitamin B1 deficiency if used long-term. Oat straw is generally safe as food during pregnancy and breastfeeding but concentrated supplements are less studied.

Common side effects from oats include bloating, gas, and abdominal distention, which usually fade with continued use. Marshmallow is generally tolerated short-term but has insufficient safety data for pregnancy and breastfeeding.

Plantain (black psyllium) is likely safe in pregnancy and breastfeeding when taken with adequate water, though it can rarely cause bowel or esophageal blockage. Wheat grass has limited human safety data and should be avoided in pregnancy and breastfeeding.

Hops may cause drowsiness and should be avoided in pregnancy; breastfeeding safety is unknown.

Side effects, ingredient by ingredient Alfalfa Horsetail Oats Marshmallow Black Psyllium Couch Grass Hops

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 6 of the 7 matched ingredients can interact with medications — Alfalfa, Black Psyllium, Marshmallow, Oats, Horsetail, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 2,223 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 with your doctor or pharmacist if you take blood thinners like warfarin, diabetes or blood sugar medications, water pills (diuretics), lithium, HIV medications (NRTIs like efavirenz), seizure drugs, antipsychotics, sedatives, birth control pills, or hormone replacement therapy. Alfalfa, horsetail, marshmallow, and plantain can all affect how these medications work.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with strong clinical evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

This product may be right for someone looking to support digestion and general wellness with herbs, and oat straw does have solid evidence for heart health. However, because alfalfa, horsetail, and plantain interact with many common medications — especially blood thinners, diabetes drugs, water pills, and lithium — you'll want to check with your own doctor or pharmacist before starting, especially if you take any prescription medications.

If you're pregnant, breastfeeding, or managing a chronic condition, talk it over with your healthcare provider first.

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

Assessment coverage: 7 of 7 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 24, 2021.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Herbal CA, straight from the product label.

Brand Nature's Sunshine
Barcode (UPC) 099904008236
Net contents 100 Capsule(s)
Market status On market
Date entered into DSLD Sep 24, 2021
DSLD ID 255293
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Kosher
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 CA by Nature's Sunshine, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
100
UPC/BARCODE
099904008236
IngredientAmount% DV
Proprietary Blend385 mg--
Alfalfa0 NP--
Horsetail0 NP--
Oat Straw extract0 NP--
Marshmallow0 NP--
Plantain0 NP--
Wheat Grass0 NP--
Hops0 NP--

Other ingredients: 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.
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.

General Statements

Bottle made from 100% post consumer recycled material. We are committed to you and our planet. Scan to learn more.

New look! Same great product

Herbal experts since 1972

Formulation

We source the world's purest ingredients, no matter where they are grown, to ensure the active nutrients are delivered just as nature intended.

Traditional structural support Guaranteed pure

Seals/Symbols

Ko Pareve (Kosher)

Formula

Ko Pareve (Kosher)

Precautions

Do not use if inner seal is missing or damaged.

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Recommended Use: Take 1 capsule with a meal three times daily.

See for yourself

Herbal CA by Nature's Sunshine label

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

What’s inside

The Ingredients in Herbal CA by Nature's Sunshine

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

Serving size1 Capsule(s) Dosage formCapsule Servings per container100 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.

Proprietary Blend

385 mg per serving

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

Interaction report

Herbal CA by Nature's Sunshine Drug Interactions

Want to check YOUR meds against Herbal CA?

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
2,222Drugs
2 Major 829 Moderate 1,391 Minor

Ingredients driving the most interactions

Marshmallow 2,040
Plantain 2,025
Hops 863
Alfalfa 583
Horsetail 188

Each ingredient & the kinds of drugs it affects

For each ingredient in Herbal CA 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

Plantain7 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

Hops4 drug types · 863 drugs

Cns Depressants

Theoretically, concomitant use of hops with sedative drugs might cause additive sedation.
Some animal research shows that hops has sedative effects.

Likelihood Possible Evidence D
Estrogens

Theoretically, concomitant use of large amounts of hops might interfere with hormone replacement therapy due to competition for estrogen receptors.
In vitro research suggests that certain hops constituents can competitively bind to estrogen receptors. However, most hops extracts contain very small amounts of these constituents.

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

Hops extract does not seem to affect the metabolism of CYP1A2 substrates.
In vitro research suggests that flavonoid constituents of hops inhibit CYP1A2 enzyme activity. However, a pharmacokinetic study in healthy postmenopausal patients shows that taking a standardized extract of spent hops containing prenylated phenols, as 59.5 mg twice daily for 2 weeks, does not affect levels of caffeine, a CYP1A2 probe substrate.

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

Theoretically, hops extract might alter metabolism of CYP3A4 substrates; however, this effect may not be clinically significant.
Animal research suggests that specific constituents of hops, called lupulones, can induce hepatic CYP3A4 enzyme activity. However, a pharmacokinetic study in healthy postmenopausal patients with normal metabolism shows that taking a standardized extract of spent hops containing prenylated phenols, as 59.5 mg twice daily for 2 weeks, decreases the concentration of alprazolam, a CYP3A4 probe substrate, by 7.6%. This reduction is unlikely to be clinically relevant.

Likelihood Possible Evidence D

Alfalfa6 drug types · 583 drugs

Warfarin (Coumadin)

Theoretically, alfalfa might reduce the anticoagulant activity of warfarin.
Alfalfa contains a large amount of vitamin K. This could theoretically interfere with the activity of warfarin.

Likelihood Probable Evidence D
Antidiabetes Drugs

Theoretically, alfalfa might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research suggests that alfalfa decreases blood sugar in diabetic mice. Also, in one case report, a diabetic patient experienced hypoglycemia after consuming alfalfa extract. Monitor blood glucose levels closely. Dose adjustments might be necessary.

Likelihood Possible Evidence D
Contraceptive Drugs

Theoretically, alfalfa might interfere with the activity of contraceptive drugs.
Alfalfa contains coumestrol, a phytoestrogen, and isoflavonoids, which have estrogenic effects.

Likelihood Possible Evidence D
Estrogens

Theoretically, alfalfa might interfere with hormone therapy.
Alfalfa contains coumestrol, a phytoestrogen, and isoflavonoids, which have estrogenic effects.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, alfalfa might decrease the efficacy of immunosuppressive therapy.
In vitro research and human case reports suggest that alfalfa may have immunostimulant effects.

Likelihood Possible Evidence D
Photosensitizing Drugs

Theoretically, concomitant use of alfalfa with photosensitizing drugs might have additive effects.
Animal research suggests that excessive doses of alfalfa may increase photosensitivity, possibly due to its chlorophyll content. It is unclear if this effect would be clinically relevant in humans.

Likelihood Possible Evidence D

Horsetail5 drug types · 188 drugs

Antidiabetes Drugs

Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Equisetum myriochaetum has demonstrated hypoglycemic activity in clinical research. In an animal diabetic model, Equisetum giganteum had hypoglycemic effects. It is unclear whether other horsetail species have hypoglycemic effects.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Laboratory research shows that various species of horsetail have diuretic properties. Due to its diuretic effects, there has been concern that taking horsetail along with potassium-depleting diuretics might increase the risk for hypokalemia. However, pharmacokinetic research in humans shows that taking horsetail 900 mg daily for 4 days does not affect urinary excretion of electrolytes, including potassium and sodium, despite having a diuretic effect similar to taking hydrochlorothiazide 25 mg daily. It is unclear if taking horsetail for a longer duration would affect electrolyte levels. Until more is known, use with caution.

Likelihood Possible Evidence D
Efavirenz (Sustiva)

Theoretically, horsetail might decrease the levels and clinical effects of efavirenz.
In two case reports, patients were found to have detectable viral loads when taking horsetail-containing supplements along with an antiretroviral regimen that included efavirenz. In one case, the antiretroviral regimen included zidovudine, lamivudine, and efavirenz; in the other case, the regimen consisted of emtricitabine, tenofovir disoproxil fumarate, and efavirenz. One month after discontinuing horsetail, the viral loads became undetectable in both cases. The exact mechanism of this interaction is unknown. It is also unclear if this interaction is specific to efavirenz or if it is related to various components of antiretroviral therapy.

Likelihood Possible Evidence D
Lithium

Theoretically, horsetail might increase the levels and adverse effects of lithium.
Animal research suggests that horsetail has diuretic properties. Theoretically, due to these potential diuretic effects, horsetail might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Possible Evidence D
Nucleoside Reverse Transcriptase Inhibitors (Nrtis)

Theoretically, horsetail might decrease the levels and clinical effects of NRTIs.
In two case reports, patients were found to have detectable viral loads when taking horsetail-containing supplements along with an antiretroviral therapy. In one case, the antiretroviral regimen included zidovudine, lamivudine, and efavirenz; in the other case, the regimen consisted of emtricitabine, tenofovir disoproxil fumarate, and efavirenz. One month after discontinuing the supplement, the viral loads became undetectable in both cases. The exact mechanism of these interactions is unknown. It is also unclear if these interactions are specific to NRTIs or if they are related to various components of antiretroviral therapy.

Likelihood Possible Evidence D

Oat Straw extract2 drug types · 86 drugs

Antidiabetes Drugs

Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Consuming oats can decrease blood glucose in patients with diabetes. In those who require insulin, taking oats 100 grams daily for 2 days reduces the insulin dose required to achieve metabolic control.

Likelihood Possible Evidence D
Insulin

Concomitant use of oats and insulin might increase the risk of hypoglycemia.
In patients with insulin-dependent type 2 diabetes, taking oats 100 grams daily for 2 days reduces the insulin dose required to achieve metabolic control.

Likelihood Possible Evidence B
The maker

Brand information

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

Nature's Sunshine

See all Nature's Sunshine products
Name
Nature's Sunshine Products, Inc
City
Spanish Fork
State
Utah
ZipCode
84660
Phone Number
1-800-223-8225
Web Address
www.naturessunshine.com
Pharmacist Counseling Corner

Herbal CA by Nature's Sunshine: Common Questions

Does Herbal CA by Nature's Sunshine interact with any medications?
Yes. Based on its ingredients, Herbal CA has a known interaction with 2,222 medications, including 2 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Herbal CA contains 7 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is it safe to take this if I'm on blood thinner medication?
No — alfalfa in this product contains high amounts of vitamin K, which can reduce how well warfarin and other blood thinners work. You must check with your doctor or pharmacist before taking this if you're on any blood thinner.
Can I take this if I have diabetes or take diabetes medications?
Possibly, but you need to clear it first. Alfalfa, horsetail, and oat straw may all lower blood sugar, so combining them with diabetes or insulin medications could raise your risk of low blood sugar (hypoglycemia). Talk to your doctor before starting.
Does this product actually work?
Oat straw extract in the blend has solid evidence for helping with high cholesterol and heart health. Plantain is effective for constipation. For alfalfa, horsetail, marshmallow, wheat grass, and hops, the evidence isn't yet established in our data.
Can I take this while pregnant?
There isn't enough safety data for most of these ingredients in pregnancy. Alfalfa is advised against due to its estrogen-like activity. Talk with your doctor or pharmacist before taking this if you're pregnant.
What are the most common side effects?
Gas, bloating, and digestive discomfort are the most common — they usually come from the fiber in plantain and oat straw and tend to ease as your body adjusts. Alfalfa and horsetail can also cause diarrhea or stomach upset.
Does this interact with birth control pills?
Yes — alfalfa has estrogen-like compounds and may theoretically reduce how well contraceptives work. If you're on birth control, check with your pharmacist or doctor before adding this supplement.

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.

Herbal CA label
Go deeper

The Full Monographs Behind Herbal CA’s Ingredients

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

Herb & supplement monograph

Alfalfa

Interacts with 583 drugs

Alfalfa is a nutrient-rich legume that people use for high cholesterol, menopause symptoms, and general wellness, but solid human evidence for most of these uses is limited. It is best avoid...

Read the full Alfalfa monograph →
Herb & supplement monograph

Horsetail

Interacts with 188 drugs

Horsetail is a traditional herb most often used as a mild diuretic and for hair, nail, and bone support, but high-quality human evidence is limited. It can cause thiamine (vitamin B1) loss w...

Read the full Horsetail monograph →
Herb & supplement monograph

Oats

Interacts with 86 drugs

Oats are a well-studied whole grain whose soluble fiber (beta-glucan) can help lower cholesterol and support heart health when eaten regularly. As a food, oats are safe for most people, and...

Read the full Oats 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

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

Couch Grass

Couch grass is a common lawn weed whose rhizome has long been used in traditional European herbal medicine, mainly for urinary and bladder complaints. High-quality human studies are lacking,...

Read the full Couch Grass monograph →
Herb & supplement monograph

Hops

Interacts with 863 drugs

Hops are most often used for sleep and mild anxiety, frequently combined with valerian, but the human evidence is limited and not very strong. They are generally well tolerated when used sho...

Read the full Hops monograph →
Sources

Sources & How We Checked

Herbal CA'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 97 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.

Alfalfa 32 references
  1. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  2. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  3. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  4. Kurzer MS, Xu X. Dietary phytoestrogens. Annu Rev Nutr 1997;17:353-81. PubMed
  5. Farber JM, Carter AO, Varughese PV, et al. Listeriosis traced to the consumption of alfalfa tablets and soft cheese [Letter to the Editor]. N Engl J Med 1990;322:338. PubMed
  6. Molgaard J, von Schenck H, Olsson AG. Alfalfa seeds lower low density lipoprotein cholesterol and apolipoprotein B concentrations in patients with type II hyperlipoproteinemia. Atherosclerosis 1987;65:173-9. PubMed
  7. Light TD, Light JA. Acute renal transplant rejection possibly related to herbal medications. Am J Transplant 2003;3:1608-9. PubMed
  8. Prete PE. The mechanism of action of L-canavanine in inducing autoimmune phenomena. Arthritis Rheum 1985;28:1198-200. PubMed
  9. Alcocer-Varela J, Iglesias A, Llorente L, Alarcon-Segovia D. Effects of L-canavanine on T cells may explain the induction of systemic lupus erythematosus by alfalfa. Arthritis Rheum 1985;28:52-7. PubMed
  10. Roberts JL, Hayashi JA. Exacerbation of SLE associated with alfalfa ingestion. N Engl J Med 1983;308:1361. DOI
  11. Feingold, R. M. Should we fear "health foods"? Arch Intern Med 7-12-1999;159(13):1502. PubMed
  12. Taormina, P. J., Beuchat, L. R., and Slutsker, L. Infections associated with eating seed sprouts: an international concern. Emerg.Infect.Dis 1999;5(5):626-634. PubMed
  13. Backer, H. D., Mohle-Boetani, J. C., Werner, S. B., Abbott, S. L., Farrar, J., and Vugia, D. J. High incidence of extra-intestinal infections in a Salmonella Havana outbreak associated with alfalfa sprouts. Public Health Rep. 2000;115(4):339-345. PubMed
  14. Mohle-Boetani J, Werner B, Polumbo M, and et al. From the Centers for Disease Control and Prevention. Alfalfa sprouts-- Arizona, California, Colorado, and New Mexico, February-April, 2001. JAMA 2-6-2002;287(5):581-582.
  15. Howard, M. B. and Hutcheson, S. W. Growth dynamics of Salmonella enterica strains on alfalfa sprouts and in waste seed irrigation water. Appl.Environ.Microbiol. 2003;69(1):548-553.
  16. Winthrop, K. L., Palumbo, M. S., Farrar, J. A., Mohle-Boetani, J. C., Abbott, S., Beatty, M. E., Inami, G., and Werner, S. B. Alfalfa sprouts and Salmonella Kottbus infection: a multistate outbreak following inadequate seed disinfection with heat and chl
  17. Strapp, C. M., Shearer, A. E., and Joerger, R. D. Survey of retail alfalfa sprouts and mushrooms for the presence of Escherichia coil O157:H7, Salmonella, and Listeria with BAX, and evaluation of this polymerase chain reaction-based system with experimen
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Oats 13 references
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Marshmallow 5 references
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Black Psyllium 18 references
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Hops 15 references
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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.

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