Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

Clark Fx Ingredients & Drug Interactions

by Mountain Meadow Herbs

Clark Fx label
See full label image
Liquid Category: Botanical With Nutrients
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

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

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

The interaction bottom line Most serious interaction: Moderate

Clark Fx is a dietary supplement by Mountain Meadow Herbs with 5 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 1,232 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Clove extract, Wormwood extract, Green Rooibos Tea extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Clark Fx by Mountain Meadow Herbs

Ask about any prescription or over-the-counter medication and we check it for interactions with Clark Fx by Mountain Meadow Herbs — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Clark Fx by Mountain Meadow 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

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 16, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

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

Why this rating?
  • The label discloses an exact amount for 0 of its 5 active ingredients.
  • “Proprietary Blend of extracts” is a proprietary blend — the label gives one combined amount (0.40 mL) without saying how much of each component you get.

Clark Fx contains five active ingredients. Vitamin C is a well-known antioxidant; clove extract comes from the flower buds and carries eugenol, an active compound; wormwood extract (also called sweet Annie) is an herbal component; green black walnut extract is sourced from the walnut plant; and green rooibos tea extract is a caffeinated-free herbal tea powder.

The product also includes distilled water, organic grain alcohol, and vegetable glycerin as inactive ingredients to deliver the active components in liquid form.

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: Vitamin C deficiency — rated "Effective" (Vitamin C) (Natural Medicines).
  • On file: Allergic rhinitis (hay fever) — rated "Possibly Effective" (Sweet Annie) (Natural Medicines).
  • On file: Anemia of chronic disease — rated "Possibly Effective" (Vitamin C) (Natural Medicines).
  • On file: Atrial fibrillation — rated "Possibly Effective" (Vitamin C) (Natural Medicines).
  • On file: Cataracts — rated "Possibly Effective" (Vitamin C) (Natural Medicines).

Evidence is established for vitamin C in preventing vitamin C deficiency and possibly effective for anemia of chronic disease, atrial fibrillation, cataracts, and reducing respiratory infections after exercise. Clove extract is possibly effective for ventilator-associated pneumonia but has insufficient reliable evidence for cough, acute pain, or dyspepsia.

Wormwood extract is possibly effective for hay fever allergies but insufficient evidence exists for liver disease, malaria, or osteoarthritis. Black walnut and rooibos extracts both lack established evidence in our data — insufficient reliable evidence is noted for heart disease, wound healing, cognitive decline, anxiety, cancer risk, cardiovascular disease, and diabetes.

What this product is specifically formulated to do isn't stated in the ingredient facts we hold.

The evidence, ingredient by ingredient Vitamin C Clove Sweet Annie Black Walnut Rooibos

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

Vitamin C is generally well tolerated at normal doses, but very high doses can cause abdominal cramps, heartburn, nausea, diarrhea, and in rare cases kidney stones or serious kidney problems. Clove is generally well tolerated as a spice but concentrated clove oil can be irritating or toxic, especially in children.

Wormwood is generally well tolerated short-term when taken orally but can rarely cause nausea, vomiting, and in isolated cases liver damage; avoid it during pregnancy because of possible harm to the developing baby. Black walnut may cause gastrointestinal upset due to tannins and can trigger allergic reactions in people with tree nut allergies.

Rooibos is generally considered safe in normal tea amounts, but high doses taken over months might cause liver problems in susceptible people.

Side effects, ingredient by ingredient Vitamin C Clove Sweet Annie Black Walnut Rooibos

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 5 matched ingredients can interact with medications — Rooibos, Clove, Sweet Annie, Vitamin C.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments; diabetes medications.
  • For scale: 1,233 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 starting Clark Fx, check with your doctor or pharmacist if you take estrogens (birth control or hormone replacement therapy), blood thinners like warfarin, blood pressure medications, cholesterol-lowering statins, medications processed by your liver enzymes (CYP2D6, CYP1A2, CYP3A4, CYP2C9, or CYP2C19), chemotherapy drugs, heart rhythm medications, thyroid medication, blood sugar medications, or any drug that could be harmed by increased absorption.

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

This product may be worth discussing with your doctor or pharmacist if you're interested in its ingredients, but because it contains multiple herbs and a significant amount of vitamin C, it's especially important to check it against any medications you take — particularly blood thinners, heart medications, blood pressure drugs, statins, chemotherapy, birth control pills, and hormone therapy. If you have a tree nut allergy, kidney disease, liver disease, or are pregnant or breastfeeding, talk with your doctor or pharmacist before using it.

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

Assessment coverage: 5 of 5 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 Clark Fx, straight from the product label.

Brand Mountain Meadow Herbs
Barcode (UPC) 7640116925410
Net contents 4 Fluid Ounce(s); 120 mL
Market status On market
Date entered into DSLD Sep 24, 2021
DSLD ID 255102
Product type Botanical With Nutrients
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Children 4 or More Years of Age, Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Clark Fx by Mountain Meadow 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:
20 Drop(s)
Maximum serving Sizes:
20 Drop(s)
Servings per container
300
UPC/BARCODE
7640116925410
IngredientAmount% DV
Vitamin C0 NP--
Proprietary Blend of extracts0.4 mL--
Clove extract0 NP--
Wormwood extract0 NP--
Green Black Walnut extract0 NP--
Green Rooibos Tea extract0 NP--

Other ingredients: distilled Water, organic Grain Alcohol, Vegetable Glycerin

Tap any ingredient to jump to its full detail below.

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

English

Nominal weight: 120 g

Suggested/Recommended/Usage/Directions

Adults and children 12 or more years of age: Take 3-20 drops 3 times daily. Shake well before use.

Precautions

Not for children under 5 years old. Store out of reach of young children.

If you are pregnant, nursing, have a medical condition, or are taking a prescription, consult your health care provider before using this product.

Dietary supplements/food supplements should not be used as a substitute for a varied diet. Do not exceed the stated recommended daily dose.

Storage

Store in a dry, cool place.

FDA Disclaimer Statement

These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure or prevent any disease.

FDA Statement of Identity

Dietary Supplement/Food Supplement

Formulation

Made in the USA.

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

See for yourself

Clark Fx by Mountain Meadow Herbs label

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

Clark Fx label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Clark Fx by Mountain Meadow Herbs

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size20 Drop(s) Dosage formLiquid Servings per container300 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.

Vitamin C

Interacts with
207 drugs
0 NP per serving

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

Proprietary Blend of extracts

0.4 mL per serving

Other (inactive) ingredients: Distilled Water, Organic Grain Alcohol, Vegetable Glycerin. These complete the product’s ingredient list but are not active constituents.

Interaction report

Clark Fx by Mountain Meadow Herbs Drug Interactions

Want to check YOUR meds against Clark Fx?

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
1,232Drugs
1,172 Moderate 60 Minor

Ingredients driving the most interactions

Clove extract 977
Wormwood extract 889
Green Rooibos Tea extract 879
Vitamin C 207

Individual Drug Interactions

The ingredients in Clark Fx interact with 1,232 drugs. Click any drug to see the details.

4 of the 5 ingredients in Clark Fx interact with drugs. Each result below shows which ingredient is responsible. Clove extract Wormwood extract Green Rooibos Tea extract Vitamin C

Each ingredient & the kinds of drugs it affects

For each ingredient in Clark Fx 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.

Clove extract7 drug types · 977 drugs

Antidiabetes Drugs

Theoretically, concomitant use of clove extracts with antidiabetes drugs might increase the risk of hypoglycemia.
Clinical and laboratory research suggest that polyphenol extracts from clove flower buds might lower blood glucose levels. Dosing adjustments for insulin or oral hypoglycemic agents may be necessary when taken with clove. Monitor blood glucose levels closely.

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

Theoretically, concomitant use of clove may increase levels of drugs metabolized by CYP1A2.
In vitro research shows that eugenol, the principal constituent of clove, can inhibit CYP1A2 in a dose-dependent manner,. This effect has not been reported in humans.

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

Theoretically, concomitant use of clove may increase levels of drugs metabolized by CYP2C9.
In vitro research shows that eugenol, the principal constituent of clove, inhibits CYP2C9 in a dose-dependent manner. This effect has not been reported in humans.

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

Theoretically, concomitant use of clove may increase levels of drugs metabolized by CYP2D6.
In vitro research shows that eugenol, the principal constituent of clove, can inhibit CYP2D6 in a dose-dependent manner. This effect has not been reported in humans.

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

Theoretically, concomitant use of clove may increase levels of drugs metabolized by CYP3A4.
In vitro research shows that eugenol, the principal constituent of clove, can inhibit CYP3A4 in a dose-dependent manner. This effect has not been reported in humans.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, clove oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Laboratory research suggests that eugenol, a constituent of clove, has antiplatelet activity. This interaction has not been reported in humans.

Likelihood Unlikely Evidence D
Ibuprofen (Advil, Others)

Theoretically, topical application of clove oil with ibuprofen might increase the absorption and side effects of topical ibuprofen.
Laboratory research shows that topical application of clove oil increases the absorption of topical ibuprofen. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Clove extract full monograph & interactions

Wormwood extract3 drug types · 889 drugs

Cytochrome P450 2B6 (Cyp2B6) Substrates

Sweet Annie may alter plasma levels and clinical effects of drugs metabolized by CYP2B6.
In vitro research shows that the Sweet Annie constituent artemisinin induces CYP2B6, possibly increasing CYP2B6 activity by 1.6-fold. However, Sweet Annie extract seems to inhibit the activity of CYP2B6 in vitro, suggesting that other constituents of Sweet Annie play a role in its effects on the overall activity of this enzyme. More information is needed to determine whether taking Sweet Annie extract affects the metabolism of CYP2B6 substrates.

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

Sweet Annie may alter plasma levels and clinical effects of drugs metabolized by CYP3A4.
In vitro research shows that the Sweet Annie constituent artemisinin induces CYP3A4, possibly increasing CYP3A4 activity by 1.9-fold. However, Sweet Annie extract seems to inhibit the activity of CYP3A4 in vitro, suggesting that other constituents of Sweet Annie play a role in its effects on the overall activity of this enzyme. More information is needed to determine whether taking Sweet Annie extract affects the metabolism of CYP3A4 substrates.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, concomitant use might have additive adverse hepatotoxic effects.
There is some concern that Sweet Annie can adversely affect the liver.

Likelihood Possible Evidence D
Wormwood extract full monograph & interactions

Green Rooibos Tea extract7 drug types · 879 drugs

Ace Inhibitors (Aceis)

Theoretically, taking rooibos with ACEIs may increase the therapeutic and adverse effects of ACEIs.
Clinical research in healthy adults shows that taking a single dose of rooibos tea, 400 mL orally, inhibits angiotensin-converting enzyme activity.

Likelihood Possible Evidence D
Atorvastatin (Lipitor)

Theoretically, taking rooibos with atorvastatin may increase the therapeutic and adverse effects of atorvastatin.
Animal research shows that consuming green rooibos extract with atorvastatin daily for 3 weeks increases the maximum plasma concentration of atorvastatin by 6-fold and reduces the clearance of atorvastatin.

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

Theoretically, taking rooibos with CYP1A2 substrates may increase the effects of CYP1A2 substrates.
In vitro research shows that the methanol extract of rooibos leaves and stems inhibits CYP1A2 enzyme activity.

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

Theoretically, taking rooibos with CYP2C19 substrates may increase the effects of CYP2C19 substrates.
In vitro research shows that the methanol extract of rooibos leaves and stems strongly inhibits CYP2C19 enzyme activity.

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

Theoretically, taking rooibos with CYP2C9 substrates may increase the effects of CYP2C9 substrates.
In vitro research shows that the methanol extract of rooibos leaves and stems inhibits CYP2C9 enzyme activity.

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

Theoretically, taking rooibos with CYP2D6 substrates may increase the effects of CYP2D6 substrates.
In vitro research shows that the methanol extract of rooibos leaves and stems inhibits CYP2D6 enzyme activity.

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

Theoretically, taking rooibos with CYP3A4 substrates may increase the effects of CYP3A4 substrates.
In vitro research shows that the methanol extract of rooibos leaves and stems strongly inhibits CYP3A4 enzyme activity.

Likelihood Possible Evidence D
Green Rooibos Tea extract full monograph & interactions

Vitamin C13 drug types · 207 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.

Likelihood Probable Evidence B
Antitumor Antibiotics

Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.

Likelihood Probable Evidence B
Warfarin (Coumadin)

High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Salsalate (Disalcid)

Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Vitamin C full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Clark Fx, from the product label.

Mountain Meadow Herbs

See all Mountain Meadow Herbs products
Name
Dr. Clark Zentrum Limited
Street Address
152 Naxxar Road #7, SGN 9030
City
San Gwann
Pharmacist Counseling Corner

Clark Fx by Mountain Meadow Herbs: Common Questions

Does Clark Fx by Mountain Meadow Herbs interact with any medications?
Yes. Based on its ingredients, Clark Fx has a known interaction with 1,232 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Clark Fx contains 5 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take this if I'm on birth control?
Vitamin C in this product may increase estrogen levels from birth control pills by up to 55%, potentially reducing contraceptive effectiveness or causing side effects. Talk with your doctor or pharmacist — they may need to adjust your dose or watch you more closely.
Is this safe during pregnancy?
Vitamin C at normal prenatal amounts is fine, but wormwood extract should be avoided during pregnancy because it may harm the developing baby. Black walnut and rooibos data are limited during pregnancy. Ask your doctor or pharmacist before using this product while pregnant.
What is wormwood extract used for?
Wormwood extract is possibly effective for hay fever allergies, but evidence for other uses like liver disease or malaria is insufficient. The product facts don't specify what Clark Fx is intended to treat.
Can I take this if I have a nut allergy?
Black walnut is a tree nut and can trigger allergic reactions in sensitive people. If you have a tree nut allergy, avoid this product or check with your doctor or pharmacist first.
Does this product contain caffeine?
Rooibos tea is naturally caffeine-free, and no other ingredients listed are caffeine sources, so this product should be caffeine-free.
What happens if I take this with a statin like Lipitor?
Rooibos in this product may increase atorvastatin levels and effects significantly, which could raise your risk of muscle pain and other side effects. Talk with your doctor or pharmacist before combining them.

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.

Clark Fx label
Go deeper

The Full Monographs Behind Clark Fx’s Ingredients

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

Herb & supplement monograph

Vitamin C

Interacts with 207 drugs

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...

Read the full Vitamin C monograph → Herb & supplement monograph

Clove

Interacts with 977 drugs

Clove is a common cooking spice that is also used in traditional medicine, especially as a topical numbing agent for tooth pain thanks to its main compound, eugenol. Food amounts are general...

Read the full Clove monograph → Herb & supplement monograph

Sweet Annie

Interacts with 889 drugs

Sweet Annie (Artemisia annua) is the source of artemisinin, a compound used in prescription antimalarial drugs. While the purified drug is well studied for malaria, the herb itself as a supp...

Read the full Sweet Annie monograph → Herb & supplement monograph

Black Walnut

Black walnut is a tree whose green hulls are traditionally used as a natural antiparasitic and digestive remedy, but solid human evidence for these uses is lacking. It contains a compound ca...

Read the full Black Walnut monograph → Herb & supplement monograph

Rooibos

Interacts with 879 drugs

Rooibos is a caffeine-free herbal tea from South Africa that is rich in antioxidants and generally considered safe as a beverage. While lab and early studies suggest possible benefits for he...

Read the full Rooibos monograph →
Sources

Sources & How We Checked

Clark Fx'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 95 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.

Vitamin C 51 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Back DJ, Breckenridge AM, MacIver M, et al. Interaction of ethinyloestradiol with ascorbic acid in man. Br Med J (Clin Res Ed) 1981;282:1516.
  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  8. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  9. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
  10. Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
  11. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  12. Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
  13. Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
  14. Smith EC, Skalski RJ, Johnson GC, Rossi GV. Interaction of ascorbic acid and warfarin. JAMA 1972;221:1166. DOI
  15. Traxer O, Huet B, Poindexter J, et al. Effect of ascorbic acid consumption on urinary stone risk factors. J Urol 2003;170:397-401.. PubMed
  16. Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
  17. Domingo JL, Gomez M, Llobet JM, Corbella J. Influence of some dietary constituents on aluminum absorption and retention in rats. Kidney Int 1991;39:598-601. PubMed
  18. Partridge NA, Regnier FE, White JL, Hem SL. Influence of dietary constituents on intestinal absorption of aluminum. Kidney Int 1989;35:1413-7. PubMed
  19. Mc Leod DC, Nahata MC. Inefficacy of ascorbic acid as a urinary acidifier (letter). N Engl J Med 1977;296:1413. DOI
  20. Hansten PD, Hayton WL. Effect of antacid and ascorbic acid on serum salicylate concentration. J Clin Pharmacol 1980;20:326-31. PubMed
  21. Dysken MW, Cumming RJ, Channon RA, Davis JM. Drug interaction between ascorbic acid and fluphenazine. JAMA 1979;241:2008. DOI
  22. Vihtamaki T, Parantainen J, Koivisto AM, et al. Oral ascorbic acid increases plasma oestradiol during postmenopausal hormone replacement therapy. Maturitas 2002;42:129-35. PubMed
  23. Slain D, Amsden JR, Khakoo RA, et al. Effect of high-dose vitamin C on the steady-state pharmacokinetics of the protease inhibitor indinavir in healthy volunteers. Pharmacotherapy 2005;25:165-70. PubMed
  24. Cheung MC, Zhao XQ, Chait A, et al. Antioxidant supplements block the response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low HDL. Arterioscler Thromb Vasc Biol 2001;21:1320-6. PubMed
  25. Feetam CL, Leach RH, Meynell MJ. Lack of a clinically important interaction between warfarin and ascorbic acid. Toxicol Appl Pharmacol 1975;31:544-7. PubMed
  26. Weintraub M, Griner PF. Warfarin and ascorbic acid: lack of evidence for a drug interaction. Toxicol Appl Pharmacol 1974;28:53-6. PubMed
  27. Lee DH, Folsom AR, Harnack L, et al. Does supplemental vitamin C increase cardiovascular disease risk in women with diabetes? Am J Clin Nutr 2004;80:1194-200. PubMed
  28. Taylor EN, Stampfer MJ, Curhan GC. Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up. J Am Soc Nephrol 2004;15:3225-32. PubMed
  29. Ward NC, Hodgson JM, Croft KD, et al. The combination of vitamin C and grape-seed polyphenols increases blood pressure: a randomized, double-blind, placebo-controlled trial. J Hypertens 2005;23:427-34.. PubMed
  30. Prasad KN. Rationale for using high-dose multiple dietary antioxidants as an adjunct to radiation therapy and chemotherapy. J Nutr 2004;134:3182S-3S. PubMed
  31. Conklin KA. Cancer chemotherapy and antioxidants. J Nutr 2004;134:3201S-3204S. PubMed
  32. Fairweather-Tait S, Hickson K, McGaw B, et al. Orange juice enhances aluminium absorption from antacid preparation. Eur J Clin Nutr. 1994;48(1):71-3.
  33. Gruenwald, J., Graubaum, H. J., Busch, R., and Bentley, C. Safety and tolerance of ester-C compared with regular ascorbic acid. Adv.Ther. 2006;23(1):171-178.
  34. Rahimi, R., Nikfar, S., Rezaie, A., and Abdollahi, M. A meta-analysis on the efficacy and safety of combined vitamin C and E supplementation in preeclamptic women. Hypertens.Pregnancy. 2009;28(4):417-434. PubMed
  35. Einerson, B., Nathorn, C., Kitiyakara, C., Sirada, M., and Thamlikitkul, V. The efficacy of ascorbic acid in suboptimal responsive anemic hemodialysis patients receiving erythropoietin: a meta-analysis. J Med.Assoc.Thai. 2011;94 Suppl 1:S134-S146.
  36. Li, G., Li, L., Yu, C., and Chen, L. Effect of vitamins C and E supplementation on Helicobacter pylori eradication: a meta-analysis. Br.J Nutr 2011;106(11):1632-1637.
  37. Chen X, Shen L, Gu X, et al. High-dose supplementation with vitamin C--induced pediatric urolithiasis: the first case report in a child and literature review. Urology. 2014;84(4):922-4. PubMed
  38. Sattar A, Willman JE, Kolluri R. Possible warfarin resistance due to interaction with ascorbic acid: case report and literature review. Am J Health Syst Pharm. 2013;70(9):782-6. PubMed
  39. Yaich S, Chaabouni Y, Charfeddine K, et al. Secondary oxalosis due to excess vitamin C intake: a cause of graft loss in a renal transplant recipient. Saudi J Kidney Dis Transpl. 2014;25(1):113-6. PubMed
  40. Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. PubMed
  41. Rumbold A, Ota E, Nagata C, Shahrook S, Crowther CA. Vitamin C supplementation in pregnancy. Cochrane Database Syst Rev. 2015;(9):CD004072. PubMed
  42. Seo MS, Kim JK, Shim JY. High-dose vitamin C promotes regression of multiple pulmonary metastases originating from hepatocellular carcinoma. Yonsei Med J. 2015;56(5):1449-52. PubMed
  43. Skelin M, Lucijanic T, Amidzic Klaric D, et al. Factors Affecting Gastrointestinal Absorption of Levothyroxine: A Review. Clin Ther. 2017 Feb;39(2):378-403. PubMed
  44. Jiang K, Tang K, Liu H, Xu H, Ye Z, Chen Z. Ascorbic acid supplements and kidney stones incidence among men and women: a systematic review and meta-analysis. Urol J. 2019;16(2):115-120.
  45. Thomas S, Patel D, Bittel B, et al. Effect of High-Dose Zinc and Ascorbic Acid Supplementation vs Usual Care on Symptom Length and Reduction Among Ambulatory Patients With SARS-CoV-2 Infection: The COVID A to Z Randomized Clinical Trial. JAMA Netw Open. 2 PubMed
  46. Giffen MA, McLemore JL. Hyperoxalosis Secondary to Intravenous Vitamin C Administration as a Non-Allopathic Treatment for Cancer. Acad Forensic Pathol 2019;9(1-2):118-126. PubMed
  47. Maike A, Sturgill D, Gallan A. Oxalate Nephropathy in a Renal Transplant Recipient After Receiving High Dose Ascorbic Acid. Am J Med Sci 2021. PubMed
  48. Shen ZY, Chen YR, Wang MC, Chang SS. High-dose vitamin C-induced acute oxalate nephropathy in a renal transplant recipient: a case report and literature review. Asian J Surg 2022. PubMed
  49. Yanase F, Spano S, Maeda A, et al. Mega-dose sodium ascorbate: a pilot, single-dose, physiological effect, double-blind, randomized, controlled trial. Crit Care 2023;27(1):371. PubMed
  50. Sharma Y, Sumanadasa S, Shahi R, et al. Efficacy and safety of vitamin C supplementation in the treatment of community-acquired pneumonia: a systematic review and meta-analysis with trial sequential analysis. Sci Rep 2024;14(1):11846. PubMed
  51. Pejcic AV, Petrovic NZ, Djordjic MD, Milosavljevic MN. Vitamin C Levels in Pregnant Women and the Efficacy of Vitamin C Supplements in Preventing Premature Rupture of Membranes: A Systematic Review and Meta-Analysis. Balkan Med J 2024;41(4):248-260. PubMed

See these in context on the Vitamin C monograph →

Clove 26 references
  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  3. Kanerva L, Estlander T, Jolanki R. Occupational allergic contact dermatitis from spices. Contact Dermatitis 1996;35:157-62. PubMed
  4. Chen SJ, Wang MH, Chen IJ. Antiplatelet and calcium inhibitory properties of eugenol and sodium eugenol acetate. Gen Pharmacol 1996;27:629-33. PubMed
  5. Malson JL, Lee EM, Murty R, et al. Clove cigarette smoking: biochemical, physiological, and subjective effects. Pharmacol Biochem Behav 2003;74:739-45. PubMed
  6. Kirsch CM, Yenokida GG, Jensen WA, et al. Non-cardiogenic pulmonary oedema due to the intravenous administration of clove oil. Thorax 1990;45:235-6. PubMed
  7. Pallares, D. E. Link between clove cigarettes and urticaria? Postgrad.Med 10-1-1999;106(4):153. PubMed
  8. Barnard, D. R. Repellency of essential oils to mosquitoes (Diptera: Culicidae). J Med Entomol. 1999;36(5):625-629. PubMed
  9. Sanchez-Perez, J. and Garcia-Diez, A. Occupational allergic contact dermatitis from eugenol, oil of cinnamon and oil of cloves in a physiotherapist. Contact Dermatitis 1999;41(6):346-347. PubMed
  10. Andersen, K. E., Johansen, J. D., Bruze, M., Frosch, P. J., Goossens, A., Lepoittevin, J. P., Rastogi, S., White, I., and Menne, T. The time-dose-response relationship for elicitation of contact dermatitis in isoeugenol allergic individuals. Toxicol.Appl PubMed
  11. Alqareer, A., Alyahya, A., and Andersson, L. The effect of clove and benzocaine versus placebo as topical anesthetics. J Dent 2006;34(10):747-750. PubMed
  12. Lane, B. W., Ellenhorn, M. J., Hulbert, T. V., and McCarron, M. Clove oil ingestion in an infant. Hum.Exp Toxicol. 1991;10(4):291-294. PubMed
  13. Quirce, S., Fernandez-Nieto, M., del, Pozo, V, Sastre, B., and Sastre, J. Occupational asthma and rhinitis caused by eugenol in a hairdresser. Allergy 2008;63(1):137-138. PubMed
  14. Srivastava, K. C. and Malhotra, N. Acetyl eugenol, a component of oil of cloves (Syzygium aromaticum L.) inhibits aggregation and alters arachidonic acid metabolism in human blood platelets. Prostaglandins Leukot.Essent.Fatty Acids 1991;42(1):73-81. PubMed
  15. Dyrbye, B. A., Dubois, L., Vink, R., and Horn, J. A patient with clove oil intoxication. Anaesth.Intensive Care 2012;40(2):365-366.
  16. Guidotti, T. L., Laing, L., and Prakash, U. B. Clove cigarettes. The basis for concern regarding health effects. West J Med 1989;151(2):220-228.
  17. Anonymous. Evaluation of the health hazard of clove cigarettes. Council on Scientific Affairs. JAMA 12-23-1988;260(24):3641-3644. DOI
  18. Romaguera, C., Alomar, A., Camarasa, J. M., Garcia, Bravo B., Garcia, Perez A., Grimalt, F., Guerra, P., Lopez, Gorretcher B., Pascual, A. M., Miranda, A., and . Contact dermatitis in children. Contact Dermatitis 1985;12(5):283-284. PubMed
  19. Hackett, P. H., Rodriguez, G., and Roach, R. C. Clove cigarettes and high-altitude pulmonary edema. JAMA 6-28-1985;253(24):3551-3552. DOI
  20. Isaacs, G. Permanent local anaesthesia and anhidrosis after clove oil spillage. Lancet 4-16-1983;1(8329):882. PubMed
  21. Saeed, S. A. and Gilani, A. H. Antithrombotic activity of clove oil. J Pak Med Assoc 1994;44(5):112-115.
  22. Hartnoll, G., Moore, D., and Douek, D. Near fatal ingestion of oil of cloves. Arch.Dis Child 1993;69(3):392-393. PubMed
  23. Srivastava, K. C. Antiplatelet principles from a food spice clove (Syzygium aromaticum L) [corrected]. Prostaglandins Leukot.Essent.Fatty Acids 1993;48(5):363-372.
  24. Jiang Q, Wu Y, Zhang H, et al. Development of essential oils as skin permeation enhancers: penetration enhancement effect and mechanism of action. Pharmaceutical Biol. 2017;55(1):1592-1600. PubMed
  25. Mohan R, Jose S, Mulakkal J, Karpinsky-Semper D, Swick AG, Krishnakumar IM. Water-soluble polyphenol-rich clove extract lowers pre- and post-prandial blood glucose levels in healthy and prediabetic volunteers: an open label pilot study. BMC Complement Alt PubMed
  26. Alharbi NFM, Ahad A, Bin Jardan YA, Al-Jenoobi FI. Effect of eugenol on cytochrome P450 1A2, 2C9, 2D6, and 3A4 activity in human liver microsomes. Saudi Pharm J 2024;32(7):102118. PubMed

See these in context on the Clove monograph →

Sweet Annie 11 references
  1. Mueller MS, Karhagomba IB, Hirt HM, Wemakor E. The potential of Artemisia annua L. as a locally produced remedy for malaria in the tropics: agricultural, chemical and clinical aspects. J Ethnopharmacol 2000;73:487-93. PubMed
  2. Rath K, Taxis K, Walz G, et al. Pharmacokinetic study of artemisinin after oral intake of a traditional preparation of Artemisia annua L. (annual wormwood). Am J Trop Med Hyg 2004;70:128-32. DOI
  3. Centers for Disease Control and Prevention (CDC). Hepatitis temporally associated with an herbal supplement containing artemisinin-Washington, 2008. MMWR Morb Mortal Wkly Rep 2009;58:854-8.
  4. Xing J, Kirby BJ, Whittington D, et al. Evaluation of P450 inhibition and induction by artemisinin antimalarials in human liver microsomes and primary human hepatocytes. Drug Metabl Dispos 2012;40(9):1757-64. PubMed
  5. Savage RL, Hill GR, Barnes J, Kenyon SH, Tatley MV. Suspected hepatotoxicity with a supercritical carbon dioxide extract of Artemisia annua in grapeseed oil used in New Zealand. Front Pharmacol. 2019;10:1448. PubMed
  6. Ruperti-Repilado FJ, Haefliger S, Rehm S, et al. Danger of herbal tea: a case of acute cholestatic hepatitis due to Artemisia annua tea. Front Med (Lausanne). 2019;6:221. PubMed
  7. Yang J, Shen Z, Liu L, et al. Clinical efficacy and safety of Artesimia annua-Sublingual immunotherapy in seasonal allergic rhinitis patients based on different intervention time. Int Arch Allergy Immunol 2022;183(8):852-859.
  8. Kane NF, Kiani BH, Desrosiers MR, Towler MJ, Weathers PJ. Artemisia extracts differ from artemisinin effects on human hepatic CYP450s 2B6 and 3A4 in vitro. J Ethnopharmacol 2022. DOI
  9. Feng Y, Cao Y, Liu Y, et al. Clinical efficacy and safety of coseasonal initiation of Artemisia annua sublingual immunotherapy on patients with Artemisia-induced rhinoconjunctivitis. Am J Otolaryngol 2023;44(5):103942. PubMed
  10. Yang J, Wang W, Shen Z, et al. Efficacy and safety of Artemisia annua sublingual immunotherapy in patients with seasonal allergic rhinoconjunctivitis over two pollen seasons. Eur Arch Otorhinolaryngol. 2023;280(11):4939-4947. PubMed
  11. Shen Z, Zhang P, Kang W, et al. Clinical efficacy in one-year treatment with Artemisia annua-SLIT drops in monosensitized and polysensitized individuals. Am J Otolaryngol 2023;44(6):104002. PubMed

See these in context on the Sweet Annie monograph →

Black Walnut 3 references
  1. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  3. Food and Drug Administration. Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA); Public Law 108-282, Title II. Accessed on May 19, 2021. Available at: https://www.fda.gov/food/food-allergensgluten-free-guidance-documents-regulatory-infor

See these in context on the Black Walnut monograph →

Rooibos 4 references
  1. Fantoukh OI, Dale OR, Parveen A, et al. Safety Assessment of Phytochemicals Derived from the Globalized South African Rooibos Tea (Aspalathus linearis) through Interaction with CYP, PXR, and P-gp. J Agric Food Chem. 2019;67(17):4967-4975.
  2. Persson IA, Persson K, Hägg S, Andersson RG. Effects of green tea, black tea and Rooibos tea on angiotensin-converting enzyme and nitric oxide in healthy volunteers. Public Health Nutr. 2010;13(5):730-7. PubMed
  3. Reddy S, Mishra P, Qureshi S, Nair S, Straker T. Hepatotoxicity due to red bush tea consumption: a case report. J Clin Anesth. 2016;35:96-98. PubMed
  4. Patel O, Muller CJF, Joubert E, et al. Pharmacokinetic Interaction of Green Rooibos Extract With Atorvastatin and Metformin in Rats. Front Pharmacol. 2019;10:1243. PubMed

See these in context on the Rooibos monograph →

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

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