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Dietary supplement

Essiac From Rene M. Caisse, RN Ingredients & Drug Interactions

by Essiac From Rene M. Caisse, RN

Capsule Category: Botanical With Nutrients
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

Essiac From Rene M. Caisse, RN is a dietary supplement by Essiac From Rene M. Caisse, RN with 5 active ingredients. Its ingredients are commonly taken for sore throat and cough, heartburn and acid reflux, digestive upset and ibs.Based on those ingredients, 2,148 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Slippery Elm bark extract, Indian Rhubarb Root Extract, Vitamin C. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Essiac From Rene M. Caisse, RN by Essiac From Rene M. Caisse, RN

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 1 of its 5 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (1.50 Gram(s)) without saying how much of each component you get.

This product contains five active ingredients in a proprietary blend: vitamin C, slippery elm bark extract, burdock root extract, sheep sorrel leaf extract, and Indian rhubarb root extract. The blend is filled out with inactive ingredients—magnesium stearate, maltodextrin, and cellulose—which are binders and flow agents.

Vitamin C is an antioxidant and immune supporter. Slippery elm, burdock, sorrel, and rhubarb are all herbal extracts used traditionally in digestive and detox preparations, though the strength of evidence for their benefits varies widely.

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: Immune system support.
  • We looked for evidence on: Common cold, Immune function, Infection resistance, Seasonal wellness.
  • The closest evidence on file: Burdock is rated "Insufficient Reliable Evidence To Rate" for Common cold (Natural Medicines).

The evidence for what this product can actually do is mixed and limited. Vitamin C is effective for vitamin C deficiency and possibly effective for anemia of chronic disease, atrial fibrillation, cataracts, and exercise-induced respiratory infections.

For the other four ingredients—slippery elm bark, burdock root, sorrel leaf, and rhubarb root—the facts show insufficient reliable evidence for the conditions they're traditionally used for, including constipation, cough, inflammatory bowel disease, and others. We hold no effectiveness data on the blend as a whole, only on the individual ingredients.

The evidence, ingredient by ingredient Slippery Elm Burdock Sorrel Rhubarb Vitamin C

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 supplement doses, but very high doses can cause abdominal cramps, heartburn, diarrhea, nausea, headache, and kidney stones (especially if you're prone to them). Slippery elm is generally well tolerated for short-term use, though full safety data are limited.

Burdock is likely safe as a food and for short-term use in healthy adults, but serious allergic reactions including anaphylaxis are rare. Sorrel is generally safe in food amounts but has a high oxalate content; large or concentrated doses can cause kidney problems.

Rhubarb root is well tolerated in food amounts and seems tolerated at medicinal doses, but long-term or overuse can cause cramping, electrolyte loss (especially potassium), and kidney damage. During pregnancy, vitamin C at normal dietary amounts is fine, but avoid high-dose supplements unless your doctor advises it.

Burdock and rhubarb root are not recommended during pregnancy. Sorrel is possibly safe during pregnancy, but slippery elm has insufficient safety data—talk with your doctor.

For breastfeeding, there's too little information on safety for all of these, so caution is advised with medicinal amounts.

Side effects, ingredient by ingredient Slippery Elm Burdock Sorrel Rhubarb Vitamin C

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?
  • 5 of the 5 matched ingredients can interact with medications — Burdock, Rhubarb, Sorrel, Slippery Elm, Vitamin C.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; cancer treatments; heart-rhythm medications.
  • For scale: 2,149 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, check with your own doctor or pharmacist if you use warfarin or other blood thinners, antiplatelet drugs like aspirin or clopidogrel, water pills (diuretics), corticosteroids, digoxin, cyclosporine, thyroid medication (levothyroxine), birth control or hormone therapy, chemotherapy drugs, psychiatric medications, protease inhibitors for HIV, any oral medications in general, or the antihistamine fexofenadine. No interactions are documented for any ingredient we could not check.

Check your own medication Run your meds through the checker above

The bottom line

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

This is a traditional herbal blend with limited evidence for what it's claimed to do. If you take a blood thinner like warfarin, are on thyroid medication, use birth control or hormone therapy, or have kidney or liver disease, you need to clear this with your own doctor or pharmacist before starting it.

The same goes if you take any regular medications—the interaction list is long, and your pharmacist can check your specific drugs against the tool on this page.

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 Jun 22, 2023.

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 Essiac From Rene M. Caisse, RN, straight from the product label.

Brand Essiac From Rene M. Caisse, RN
Barcode (UPC) 623326018971
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Jun 22, 2023
DSLD ID 290184
Product type Botanical With Nutrients
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Essiac From Rene M. Caisse, RN by Essiac From Rene M. Caisse, RN, 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 Capsule(s), 3 Capsule(s)
Maximum serving Sizes:
2 Capsule(s), 3 Capsule(s)
Servings per container
20
UPC/BARCODE
623326018971
IngredientAmount% DV
Proprietary Blend1.5 Gram(s)--
Vitamin C1 mg2%
Slippery Elm bark extract0 NP--
Burdock Root Extract0 NP--
Sheep Sorrel leaf Extract0 NP--
Indian Rhubarb Root Extract0 NP--

Other ingredients: Magnesium Stearate, Maltodextrin, Cellulose

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.
Precautions

Do not use if safety seal under cap is broken.

CAUTION Not to be taken by pregnant women or nursing mothers.

Keep out of reach of children.

Beware of Counterfeits

Suggested/Recommended/Usage/Directions

Directions for use (Adults): Take 2 capsules twice daily for daily use. Take: 3 capsules three times daily for other health situations, one hour before or after meals. For prolonged use, consult a health care practitioner.

FDA Statement of Identity

Dietary Supplement

Formulation

Immune System Support Vegetable capsules

GMO Free Gluten-Free

Made only in Canada Exported Worldwide

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.

General Statements

1888-1978 NPN 80015598 Proprietary Formula Authorized by Rene M Caisse Trusted Worldwide Since 1922

Brand IP Statement(s)

Copyright 2016. All rights reserved

Formula

Essiac from Rene M. Caisse, RN 500 mg

See for yourself

Essiac From Rene M. Caisse, RN by Essiac From Rene M. Caisse, RN label

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

What’s inside

The Ingredients in Essiac From Rene M. Caisse, RN by Essiac From Rene M. Caisse, RN

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

Serving size2 Capsule(s) Dosage formCapsule Servings per container20 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
1 mg 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

Other (inactive) ingredients: Magnesium Stearate, Maltodextrin, Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

Essiac From Rene M. Caisse, RN by Essiac From Rene M. Caisse, RN Drug Interactions

Want to check YOUR meds against Essiac From Rene M. Caisse, RN?

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
2,148Drugs
2,148 Moderate

Each ingredient & the kinds of drugs it affects

For each ingredient in Essiac From Rene M. Caisse, RN 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.

Slippery Elm bark extract1 drug type · 2,022 drugs

Oral Drugs

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

Likelihood Possible Evidence D

Indian Rhubarb Root Extract8 drug types · 658 drugs

Corticosteroids

Theoretically, frequent and high doses of rhubarb might increase the risk of hypokalemia when taken with corticosteroids.
Rhubarb has stimulant laxative effects. Overuse of rhubarb might compound corticosteroid-induced potassium loss.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, taking rhubarb with cyclosporine might reduce cyclosporine levels.
Animal research shows that co-administration of rhubarb decoction 0.25 or 1 gram/kg with cyclosporine 2.5 mg/kg, decreases cyclosporine maximum plasma concentration and overall exposure levels when compared with taking cyclosporine alone. The authors theorize that rhubarb might reduce cyclosporine bioavailability by inducing of P-glycoprotein and/or cytochrome P450 3A4. However, since rhubarb was administered as a single oral dose and enzyme induction usually occurs after multiple doses, it is possible that cyclosporine absorption was actually reduced via rhubarb's stimulant laxative effects. Also, the composition of the rhubarb decoction was not described.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, overuse of rhubarb might increase the risk of adverse effects when taken with digoxin.
Rhubarb has stimulant laxative effects. Overuse of rhubarb might cause potassium depletion, increasing the risk of digoxin toxicity.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, frequent and high doses of rhubarb might increase the risk of hypokalemia.
Rhubarb has stimulant laxative effects. Overuse of rhubarb might cause potassium depletion and compound diuretic-induced potassium loss.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, concomitant use of rhubarb with potentially hepatotoxic drugs might increase the risk of developing liver damage.
Some animal research suggests that anthraquinones in rhubarb might have hepatotoxic effects. Also, rhubarb use has been linked to at least 24 cases of liver injury, although details on the dose of rhubarb and duration of use in these cases is unclear.

Likelihood Possible Evidence D
Nephrotoxic Drugs

Theoretically, long-term use of anthraquinones from rhubarb might increase the risk of nephrotoxicity when used with nephrotoxic drugs.
The anthraquinone constituents of rhubarb have been shown to induce nephrotoxicity in animal research. Additionally, in a case report, a 23-year old female presented with kidney failure after taking 6 tablets of a proprietary slimming agent (found to contain the anthraquinones emodin and aloe-emodin from rhubarb) daily for 6 weeks and then adding diclofenac 25 mg 4 times daily for 2 days. The authors postulate that the anthraquinone constituents of rhubarb contributed to the renal dysfunction, and the addition of diclofenac, a nephrotoxic drug, led to renal failure. Until more is known, advise patients to avoid taking rhubarb if they are taking other potentially nephrotoxic drugs.

Likelihood Possible Evidence D
Stimulant Laxatives

Theoretically, rhubarb might increase the risk for fluid and electrolyte loss when taken with other stimulant laxatives.
Rhubarb has stimulant laxative effects. Concomitant use with stimulant laxatives might compound fluid and electrolyte loss.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, excessive use of rhubarb might increase the risk of bleeding when taken with warfarin.
Rhubarb has stimulant laxative effects and can cause diarrhea. Diarrhea can increase the effects of warfarin, increase international normalized ratio (INR), and increase the risk of bleeding. Advise patients who take warfarin not to take excessive amounts of rhubarb.

Likelihood Possible Evidence D

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

Sheep Sorrel leaf Extract3 drug types · 169 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, sorrel might cause additive effects and side effects when used with anticoagulant or antiplatelet drugs.
In vitro, sorrel has been shown to inhibit platelet aggregation. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Fexofenadine (Allegra)

Sorrel might reduce the effectiveness of fexofenadine by reducing its absorption from the gut.
In vitro research shows that an ethanol extract of sorrel inhibits organic anion-transporting polypeptide 1A2 (OATP1A2), which transports fexofenadine from the intestine into cells. In rats, concomitant administration of sorrel extract with fexofenadine reduces oral absorption of fexofenadine and the area under the plasma concentration-time curve (AUC).

Likelihood Likely Evidence D
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Sorrel might reduce the effectiveness of OATP substrates by reducing their absorption from the gut.
In vitro research shows that sorrel inhibits OATP1A2. Theoretically it may inhibit other OATPs. The OATPs are expressed in the small intestine and liver and transport drugs into cells. Inhibition of OATP may reduce the bioavailability of oral drugs that are substrates of OATP.

Likelihood Possible Evidence D

Burdock Root Extract1 drug type · 122 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, taking burdock with anticoagulant or antiplatelet drugs might increase the risk of bleeding.

In vitro research shows that lignans from burdock reduce rabbit platelet aggregation by inhibiting platelet activating factor. This interaction has not been reported in humans.

Likelihood Possible Evidence D
The maker

Brand information

Manufacturer and brand details for Essiac From Rene M. Caisse, RN, from the product label.

Essiac From Rene M. Caisse, RN

See all Essiac From Rene M. Caisse, RN products
Name
ESSIAC FROM CANADA INT'L
City
Ottawa
State
Ontario
ZipCode
K1P 5P6
Phone Number
(561) 223-6003
Pharmacist Counseling Corner

Essiac From Rene M. Caisse, RN by Essiac From Rene M. Caisse, RN: Common Questions

Does Essiac From Rene M. Caisse, RN by Essiac From Rene M. Caisse, RN interact with any medications?
Yes. Based on its ingredients, Essiac From Rene M. Caisse, RN has a known interaction with 2,148 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Essiac From Rene M. Caisse, RN 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.
Is it safe to take Essiac while pregnant?
The ingredients have mixed safety profiles in pregnancy. Vitamin C at normal dietary amounts is fine, but avoid high-dose supplements unless your doctor advises it. Burdock and rhubarb root are not recommended during pregnancy. Sorrel is possibly safe, but slippery elm doesn't have enough data. Talk with your doctor or midwife about whether this product is right for you.
Can I take this if I'm breastfeeding?
There isn't enough safety information on any of these ingredients for breastfeeding, so medicinal amounts are best avoided. Talk with your doctor or pharmacist about your individual situation.
What is slippery elm supposed to do?
Slippery elm has been used traditionally for digestive issues like cough, inflammatory bowel disease, and constipation. However, we don't have reliable evidence that it actually works for any of these conditions.
Does rhubarb root cause cramping?
Yes. Rhubarb root has laxative effects and commonly causes cramping, diarrhea, and gastrointestinal discomfort, especially with overuse. It shouldn't be used long-term.
Why does vitamin C interact with so many medications?
Vitamin C is an antioxidant that affects how your body absorbs and processes other drugs. At high doses it can thin the blood, reduce absorption of some medications, increase levels of others (like estrogen and thyroid medication), and interfere with how chemotherapy works.
What are the inactive ingredients in this capsule?
The capsule contains magnesium stearate, maltodextrin, and cellulose—these are binders and fillers that help hold the formula together and fill the capsule.

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.

Essiac From Rene M. Caisse, RN label
Go deeper

The Full Monographs Behind Essiac From Rene M. Caisse, RN’s Ingredients

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

Sources

Sources & How We Checked

Essiac From Rene M. Caisse, RN'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 93 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
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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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