Interactions on record — worth a quick check against your medications. Based on 7 of 8 ingredients. Check your meds →
Dietary supplement

RST-C Ingredients & Drug Interactions

by Pure Herbs

Liquid Category: Botanical
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

RST-C is a dietary supplement by Pure Herbs with 8 active ingredients. Its ingredients are commonly taken for skin irritation and itching, minor wounds and cuts, digestive upset.Based on those ingredients, 1,347 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Fo-Ti Root Extract, Kelp Whole Algae Extract, Calendula Flower Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of RST-C by Pure Herbs

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 8 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (1,983 mg) without saying how much of each component you get.

RST-C contains eight active ingredients in a proprietary blend. The standouts are fo-ti root extract (used traditionally for vitality and hair health), chickweed aerial parts extract (historically used for skin and weight support), arrowroot root extract (traditionally used for digestive comfort), and calendula flower extract (known for skin support).

The blend also includes two whole algae extracts—kelp and bladderwrack—plus Irish moss extract and white mustard seed extract. There are no other inactive ingredients listed.

Does it work?

Not established
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
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: relieve occasional joint stiffness and discomfort.
  • We looked for evidence on: Osteoarthritis, Joint pain, Musculoskeletal discomfort, Post-exercise soreness.
  • The closest evidence on file: Fo-ti is rated "Insufficient Reliable Evidence To Rate" for Osteoarthritis (Natural Medicines).

The evidence supporting most ingredients in this blend is not established in our data. Chickweed, arrowroot, calendula, and fo-ti all carry ratings of insufficient reliable evidence for their traditional uses—meaning the research to confirm they work for these purposes isn't solid yet.

White mustard seed has no effectiveness ratings on file. The other ingredients lack effectiveness data we can review.

This doesn't mean they don't work; it means the clinical evidence we hold doesn't establish it.

The evidence, ingredient by ingredient Chickweed Arrowroot Fucus Vesiculosus Calendula Fo-ti Sea Moss White Mustard

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 7 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.

Fo-ti is the safety concern here. It has been linked to liver injury in around 450 documented cases, ranging from mild hepatitis to cirrhosis.

Liver damage occurred across a wide range of doses and durations, so there's no safe threshold we can identify. It commonly causes abdominal pain, diarrhea, nausea, and vomiting—especially with raw or unprocessed forms.

Fo-ti is rated possibly unsafe in pregnancy and lactation, and chickweed is rated best avoided in both. Calendula is rated likely unsafe in pregnancy.

Arrowroot and white mustard seed lack strong safety data for pregnancy and concentrated use. Calendula can cause allergic reactions, especially in people sensitive to ragweed or related plants.

White mustard seed can cause allergic skin reactions and stomach irritation. Chickweed is generally considered low-risk for short-term use, but high-quality safety data are limited.

Side effects, ingredient by ingredient Chickweed Arrowroot Fucus Vesiculosus Calendula Fo-ti Sea Moss White Mustard

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?
  • 4 of the 7 matched ingredients can interact with medications — Calendula, Fucus Vesiculosus, Fo-ti, Sea Moss.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 1,348 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.

If you take warfarin or any other blood thinner (anticoagulant), do not start this product without checking with your pharmacist or doctor first—fo-ti carries Moderate risk of increased bleeding. Also double-check before use if you take heart medications (digoxin), anti-inflammatory drugs (sulindac), drugs metabolized by liver enzymes (CYP2C8 or CYP2B6 substrates), diuretics, stimulant laxatives, or CNS depressants (sedating medications).

Altogether, these interactions span 1,312 individual medications.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

This product is built on traditional herbs with limited clinical proof they work. The real concern is fo-ti, which carries documented liver injury risk and interacts with blood thinners and several other drug classes.

If you take any prescription medications—especially warfarin or other anticoagulants, heart drugs, diuretics, or medications metabolized by your liver—talk to your pharmacist or doctor before starting. Pregnant or breastfeeding?

Skip this one; several ingredients lack adequate safety data or are advised against.

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

Assessment coverage: 8 of 8 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 21, 2024.

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

At a glance

General information

Key facts about RST-C, straight from the product label.

Brand Pure Herbs
Net contents 1 Fluid Ounce(s); 30 mL
Market status On market
Date entered into DSLD Dec 21, 2024
DSLD ID 327250
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 RST-C by Pure Herbs, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
2 mL
Maximum serving Sizes:
2 mL
Servings per container
15
IngredientAmount% DV
Proprietary Blend1983 mg--
Chickweed aerial parts extract0 NP--
Arrowroot Root Extract0 NP--
Kelp Whole Algae Extract0 NP--
Bladderwrack Algae Extract0 NP--
Calendula Flower Extract0 NP--
Fo-Ti Root Extract0 NP--
Irish Moss Extract0 NP--
White Mustard Seed Extract0 NP--

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

Directions: For adults, mix 2 mL (abt. 1/2 tsp) of extract in 2 fl. oz (60 mL) water one time daily preferably with a meal.

Shake well before use

Formulation

Helps to relieve occasional stiffness and joint discomfort after periods of physical exertion.

FDA Disclaimer Statement

This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Precautions

Warning: Not intended for use by pregnant or nursing women. If you have a medical condition or are taking medication, consult your doctor prior to use.

Discontinue use and consult with your doctor if any adverse reactions occur.

Keep out of reach of children.

Brand IP Statement(s)

Pure Herbs, LTD. Natural Herbal Extracts

FDA Statement of Identity

Dietary Supplement

General Statements

"No expense has been spared to provide the finest nature has to offer."

See for yourself

RST-C by Pure Herbs label

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

What’s inside

The Ingredients in RST-C by Pure Herbs

These are the 8 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 mL Dosage formLiquid Servings per container15 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.

Interaction report

RST-C by Pure Herbs Drug Interactions

Want to check YOUR meds against RST-C?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

Go to the checker
1,347Drugs
1,272 Moderate 75 Minor

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in RST-C 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.

Fo-Ti Root Extract17 drug types · 1,257 drugs

Anticoagulant/Antiplatelet Drugs

Fo-ti has been linked to cases of acute liver failure which can decrease clotting factor production and increase the effects of anticoagulants. In one case, a patient who had been stable on warfarin presented with acute hepatitis and an INR elevated to 14.98. The patient had been taking fo-ti for 90 days prior to admission. Discontinuation of warfarin and fo-ti lead to a decrease in the INR and full recovery. Theoretically, concomitant use of fo-ti with anticoagulant or antiplatelet drugs may increase the risk of bleeding in some patients. Until more is known, monitor patients taking fo-ti and drugs that affect bleeding.
Some of these drugs include aspirin, clopidogrel (Plavix), dalteparin (Fragmin), dipyridamole (Persantine), enoxaparin (Lovenox), heparin, ticlopidine (Ticlid), warfarin (Coumadin), and others.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, fo-ti might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Fo-ti reportedly has hypoglycemic effects.

Likelihood Possible Evidence D
Contraceptive Drugs

Theoretically, taking large amounts of fo-ti might interfere with contraceptive drugs due to competition for estrogen receptors.
In vitro research suggests that fo-ti extract has estrogenic activity.

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

Theoretically, fo-ti might increase or decrease the levels and clinical effects of drugs metabolized by CYP1A2.
In vitro research suggests that fo-ti might inhibit CYP1A2. Additionally, in vitro research suggests that the degree of CYP1A2 inhibition depends on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts). However, in an animal study, an aqueous extract of fo-ti inhibited CYP1A2 while an alcoholic extract of fo-ti induced CYP1A2. Induction or inhibition of CYP1A2 by fo-ti has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2B6 (Cyp2B6) Substrates

Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP2B6.
Animal research suggests that fo-ti might inhibit CYP2B6. One in vitro study suggests that the degree of CYP2B6 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts). However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2C19.
Animal and in vitro research suggests that fo-ti may inhibit CYP2C19. An in vitro study suggests that the degree of CYP2C19 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts). However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C8 (Cyp2C8) Substrates

Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP2C8.
In vitro research suggests that fo-ti might inhibit CYP2C8. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2C9.
Animal and in vitro research suggests that fo-ti may inhibit CYP2C9. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2D6.
Animal research suggests that fo-ti might inhibit CYP2D6. Additionally, an in vitro study suggests that the degree of CYP2D6 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts). However, this interaction has not been reported in humans.

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

Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP3A4.
In vitro research suggests that fo-ti might inhibit CYP3A4. One in vitro study suggests that the degree of CYP3A4 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts). However, this evidence conflicts with animal research suggesting that fo-ti does not inhibit CYP3A4. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, fo-ti, particularly raw fo-ti root, might increase the risk of hypokalemia and cardiotoxicity when taken with digoxin.
Raw fo-ti root contains anthraquinone derivatives, which might have stimulant laxative effects. In vitro research shows that fermented and processed fo-ti root have reduced laxative effects compared with raw fo-ti root.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, fo-ti, particularly raw fo-ti root, might increase the risk of hypokalemia when taken with diuretic drugs.
Raw fo-ti root contains anthraquinone derivatives, which might have stimulant laxative effects and compound diuretic-induced potassium loss. In vitro research shows that fermented and processed fo-ti root have reduced laxative effects compared with raw fo-ti root.

Likelihood Possible Evidence D
Estrogens

Theoretically, taking large amounts of fo-ti might interfere with hormone replacement therapy through competition for estrogen receptors.
In vitro research suggests that fo-ti extract has estrogenic activity.

Likelihood Probable Evidence D
Hepatotoxic Drugs

Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Fo-ti has been linked to liver damage in many reports.

Likelihood Possible Evidence D
Stimulant Laxatives

Theoretically, fo-ti, particularly raw fo-ti root, might increase the risk of fluid and electrolyte depletion when taken with stimulant laxatives.
Raw fo-ti root contains anthraquinone derivatives, which might have stimulant laxative effects. However, in vitro research shows that fermented and processed fo-ti root have reduced laxative effects compared with raw fo-ti root.

Likelihood Possible Evidence D
Sulindac (Clinoril)

Theoretically, fo-ti might increase or decrease the levels and clinical effects of sulindac.
Animal research suggests that the type of fo-ti extract might affect the levels of sulindac differently; the raw plant may increase levels, but processed parts may decrease levels. Induction or inhibition of CYP1A2 by fo-ti has not been reported in humans.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, fo-ti might increase the effects and adverse effects of warfarin.
Fo-ti may have stimulant laxative effects and cause diarrhea, especially when the raw or unprocessed fo-ti root is used. Diarrhea can increase the effects of warfarin, increase international normalized ratio (INR), and increase the risk of bleeding. Also, fo-ti has been linked to cases of acute liver failure which can decrease clotting factor production and increase the effects of warfarin. In one case, a patient who had been stable on warfarin presented with acute hepatitis and an INR elevated to 14.98. The patient had been taking fo-ti for 90 days prior to admission. Discontinuation of warfarin and fo-ti lead to a decrease in the INR and full recovery.

Likelihood Possible Evidence D

Kelp Whole Algae Extract9 drug types · 891 drugs

Amiodarone (Cordarone)

Theoretically, combining Fucus vesiculosus with amiodarone might cause excessively high iodine levels.
Fucus vesiculosus contains high concentrations of iodine. Amiodarone contains 37.3% iodine and can increase iodine levels. Concomitant use might increase the risk of having excessive iodine levels and adversely affecting thyroid function. Monitor thyroid function.

Likelihood Probable Evidence D
Antithyroid Drugs

Due to its iodine content, Fucus vesiculosus might alter the effects of antithyroid drugs.
Fucus vesiculosus contains high concentrations of iodine. Iodine in high doses has been reported to cause both hyperthyroidism and hypothyroidism, depending on the individual's past medical history. Taking Fucus vesiculosus while using antithyroid drugs could alter the effects of the antithyroid drugs.

Likelihood Possible Evidence D
Lithium

Concomitant use of Fucus vesiculosus and lithium has resulted in hyperthyroidism.
There is a case of hyperthyroidism occurring in a patient taking Fucus vesiculosus and lithium. Monitor thyroid hormones closely in patients taking lithium and Fucus vesiculosus concomitantly.

Likelihood Possible Evidence D
Thyroid Hormone

Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Fucus vesiculosus contains high concentrations of iodine. Iodine in high doses has been reported to cause both hyperthyroidism and hypothyroidism, depending on the individual's past medical history. Taking Fucus vesiculosus while using thyroid hormone could alter the effects of thyroid hormone.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, taking Fucus vesiculosus with antiplatelet or anticoagulant drugs might increase the risk of bruising and bleeding.
In vitro evidence suggests that a constituent of Fucus vesiculosus, known as fucoidan, has anticoagulant effects. However, in clinical research, fucoidan does not seem to have significant anticoagulant activity when taken orally, possibly due to poor absorption.

Likelihood Unlikely Evidence D
Cytochrome P450 2C8 (Cyp2C8) Substrates

Theoretically, concomitant use of Fucus vesiculosus with CYP2C8 substrates might increase the risk for adverse effects.
In vitro research shows that fucoidan, a constituent of Fucus vesiculosus, inhibits CYP2C8. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, concomitant use of Fucus vesiculosus with CYP2C9 substrates might increase the risk for adverse effects.
In vitro research shows that fucoidan, a constituent of Fucus vesiculosus, inhibits CYP2C9. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, concomitant use of Fucus vesiculosus with CYP2D6 substrates might alter the effects of these substrates.
In vitro research shows that fucoidan, a constituent of Fucus vesiculosus, both inhibits and induces CYP2D6. This interaction has not been reported in humans.

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

Theoretically, concomitant use of Fucus vesiculosus with CYP3A4 substrates might increase the risk for adverse effects.
In vitro research shows that fucoidan, a constituent of Fucus vesiculosus, inhibits CYP3A4. This interaction has not been reported in humans.

Likelihood Possible Evidence D

Calendula Flower Extract1 drug type · 248 drugs

Cns Depressants

Theoretically, calendula might have additive effects when used with CNS depressants, although this appears to be unlikely.
Although some animal research has suggested that a saponoside constituent in calendula may have sedative effects, calendula has been used for over 30 years without reports of sedation in humans.

Likelihood Unlikely Evidence D

Irish Moss Extract3 drug types · 22 drugs

Amiodarone (Cordarone)

Theoretically, combining sea moss with amiodarone might cause excessively high iodine levels.
Amiodarone contains 37.3% iodine and can increase iodine levels. Concomitant use with sea moss, which contains approximately 4-7 mcg of iodine per gram, might increase the risk of adverse effects from iodine, including altered thyroid function.

Likelihood Possible Evidence D
Antithyroid Drugs

Due to its iodine content, sea moss might alter the effects of antithyroid drugs.
Sea moss contains approximately 4-7 mcg of iodine per gram. Iodine in high doses has been reported to cause both hyperthyroidism and hypothyroidism, depending on the individual's past medical history. Taking sea moss could theoretically alter the effects of antithyroid drugs.

Likelihood Possible Evidence D
Thyroid Hormone

Due to its iodine content, sea moss might alter the effects of thyroid hormone.
Sea moss contains approximately 4-7 mcg of iodine per gram. Iodine in high doses has been reported to cause both hyperthyroidism and hypothyroidism, depending on the individual's past medical history. Taking sea moss could theoretically alter the effects of thyroid hormone.

Likelihood Possible Evidence D
The maker

Brand information

Manufacturer and brand details for RST-C, from the product label.

Pure Herbs

See all Pure Herbs products
Name
Pure Herbs, Ltd.
City
Sterling Heights
State
MI
Phone Number
(800) 860-4372
Web Address
www.pureherbs.com
Pharmacist Counseling Corner

RST-C by Pure Herbs: Common Questions

Does RST-C by Pure Herbs interact with any medications?
Yes. Based on its ingredients, RST-C has a known interaction with 1,347 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
RST-C contains 8 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 this safe to take while I'm pregnant?
No. Fo-ti is rated possibly unsafe, chickweed is best avoided, and calendula is likely unsafe during pregnancy. The safety data for the other ingredients are also limited. Talk with your doctor before considering any supplement during pregnancy.
Will this help with weight or blood sugar?
The evidence isn't established in our data. Chickweed and arrowroot are rated insufficient reliable evidence for weight and blood sugar support. That doesn't mean they won't help, just that the clinical research we hold doesn't confirm it yet.
What should I watch for if I do take this?
Fo-ti commonly causes diarrhea, abdominal pain, nausea, and vomiting. Calendula and white mustard seed can cause allergic reactions, particularly skin irritation. If you develop yellowing of the skin or eyes, dark urine, or severe abdominal pain—signs of liver trouble—stop and see your doctor right away.
Is this safe to take while breastfeeding?
No. Fo-ti and chickweed are both advised against while breastfeeding because safety data are insufficient. Talk with your doctor about what's safe for you and your baby.
What is fo-ti used for?
Fo-ti is traditionally used to support healthy hair, cognitive function, and heart health. However, the clinical evidence to confirm these benefits isn't solid in our data.
Can I take this with my allergy medication?
Calendula in this blend carries a minor interaction with CNS depressants (sedating drugs), which some allergy medications are. If your allergy medicine is sedating, check with your pharmacist before adding this product.

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.

RST-C label
Go deeper

The Full Monographs Behind RST-C’s Ingredients

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

Herb & supplement monograph

Chickweed

Chickweed is a common edible wild plant traditionally used on the skin for itching and minor irritation, and taken as a tea or tincture for various complaints. Solid human studies are lackin...

Read the full Chickweed monograph →
Herb & supplement monograph

Arrowroot

Arrowroot is a starch made from the roots of Maranta arundinacea and is mainly used as a gentle, easy-to-digest thickening agent in food. Some people use it for diarrhea and digestive discom...

Read the full Arrowroot monograph →
Herb & supplement monograph

Fucus Vesiculosus

Interacts with 891 drugs

Fucus vesiculosus (bladderwrack) is a brown seaweed rich in iodine that has been used traditionally for thyroid concerns, weight, and skin. There is little solid human evidence to support mo...

Read the full Fucus Vesiculosus monograph →
Herb & supplement monograph

Calendula

Interacts with 248 drugs

Calendula is a flowering plant whose petals are used mainly in skin creams, oils, and ointments to soothe minor irritation and support wound healing. Some early research is promising for ski...

Read the full Calendula monograph →
Herb & supplement monograph

Fo-ti

Interacts with 1,257 drugs

Fo-ti (He Shou Wu) is a root used in traditional Chinese medicine, often promoted for healthy aging and hair. High-quality human evidence for these benefits is limited, and processed Fo-ti h...

Read the full Fo-ti monograph →
Herb & supplement monograph

Sea Moss

Interacts with 22 drugs

Sea moss is a type of red seaweed that is naturally rich in iodine and several minerals, and it is popular as a 'whole-food' supplement. Strong human evidence for most of its health claims i...

Read the full Sea Moss monograph →
Herb & supplement monograph

White Mustard

White mustard is best known as a culinary seed used to make the mustard condiment, and it has a long history in folk medicine for digestion and as a warming topical plaster. Solid human evid...

Read the full White Mustard monograph →
Sources

Sources & How We Checked

RST-C'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 64 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.

Chickweed 4 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. Jovanovic M, Mimica-Dukic N, Poljacki M, Boza P. Erythema multiforme due to contact with weeds: a recurrence after patch testing. Contact Dermatitis 2003;48:17-25. PubMed
  3. Jovanovic, M., Poljacki, M., Mimica-Dukic, N., Boza, P., Vujanovic, Lj, Duran, V., and Stojanovic, S. Sesquiterpene lactone mix patch testing supplemented with dandelion extract in patients with allergic contact dermatitis, atopic dermatitis and non-alle
  4. Poljacki, M., Jovanovic, M., Boza, P., Mimica-Dukic, N., Petrovic, A., and Novovic, Z. [Is Vojvodina a risk area for contact weed allergies?]. Med Pregl. 2005;58(3-4):123-126. PubMed

See these in context on the Chickweed monograph →

Arrowroot 2 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. Cooke, C., Carr, I., Abrams, K., and Mayberry, J. Arrowroot as a treatment for diarrhoea in irritable bowel syndrome patients: a pilot study. Arq Gastroenterol. 2000;37(1):20-24. PubMed

See these in context on the Arrowroot monograph →

Fucus Vesiculosus 15 references
  1. Goodman GA, Rall TW, Nies AS, Taylor P. The Pharmacological Basis of Therapeutics, 9th ed.
  2. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
  3. Phaneuf D, Cote I, Dumas P, et al. Evaluation of the contamination of marine algae (Seaweed) from the St. Lawrence River and likely to be consumed by humans. Environ Res 1999;80:S175-S182. PubMed
  4. Durig J, Bruhn T, Zurborn KH, et al. Anticoagulant fucoidan fractions from Fucus vesiculosus induce platelet activation in vitro. Thromb Res 1997;85:479-91. PubMed
  5. Conz PA, La Greca G, Benedetti P, et al. Fucus vesiculosus: a nephrotoxic alga? Nephrol Dial Transplant 1998;13:526-7.
  6. Ohye H, Fukata S, Kanoh M, et al. Thyrotoxicosis caused by weight-reducing herbal medicines. Arch Intern Med 2005;165:831-4. PubMed
  7. Okamura K, Inoue K, Omae T. A case of Hashimoto's thyroiditis with thyroid immunological abnormality manifested after habitual ingestion of seaweed. Acta Endocrinol (Copenh) 1978;88:703-12. PubMed
  8. Agarwal SC, Crook JR, Pepper CB. Herbal remedies -- how safe are they? A case report of polymorphic ventricular tachycardia/ventricular fibrillation induced by herbal medication used for obesity. Int J Cardiol 2006;106:260-1. PubMed
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Calendula 9 references
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Sea Moss 3 references
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White Mustard 3 references
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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.

© 2021 Therapeutic Research Center, LLC

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