Major interaction on record — check this product against your medications before combining. Based on 9 of 11 ingredients. Check your meds →
Dietary supplement

Colon Cleanse Ingredients & Drug Interactions

by 21st Century

Colon Cleanse label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Colon Cleanse 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: Major

Colon Cleanse is a dietary supplement by 21st Century with 11 active ingredients. Its ingredients are commonly taken for high cholesterol, digestive health and fiber, heart health support.Based on those ingredients, 1,510 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Ginger, Cascara Sagrada, Fennel. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Colon Cleanse by 21st Century

Ask about any prescription or over-the-counter medication and we check it for interactions with Colon Cleanse by 21st Century — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Colon Cleanse by 21st Century

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 12, 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 11 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (2,000 mg) without saying how much of each component you get.

Colon Cleanse contains 11 ingredients total. The active components are rice bran, alfalfa, fennel, cascara sagrada, rhubarb, psyllium, ginger, red raspberry leaf, and wheat grass.

Cascara sagrada and rhubarb are both stimulant laxatives—they're included to promote bowel movement. Psyllium is a soluble fiber that absorbs water and adds bulk to stool.

Bentonite is a type of clay that may absorb water and unwanted substances in the intestines. The remaining botanical ingredients—rice bran, alfalfa, fennel, ginger, red raspberry, and wheat grass—are traditional digestive or general wellness herbs.

The product also contains inactive ingredients: cellulose, oat fiber, and magnesium stearate.

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: cleanse digestive system and support colon health.
  • We looked for evidence on: Bowel preparation, Constipation, Dyspepsia, Flatulence, Irritable bowel syndrome (IBS), Digestive health — and 2 related terms.
  • The closest evidence on file: Cascara Sagrada is rated "Possibly Ineffective" for Bowel preparation (Natural Medicines).
  • Also on file: Alfalfa is rated "Insufficient Reliable Evidence To Rate" for Dyspepsia.
  • Also on file: Rhubarb is rated "Insufficient Reliable Evidence To Rate" for Constipation.

The evidence for this product's individual ingredients is mixed and often insufficient. Rhubarb has possibly effective evidence for pancreatitis and menopausal symptoms, but insufficient evidence for constipation itself.

Ginger is possibly effective for pregnancy-related nausea, menstrual cramps, and osteoarthritis, but possibly ineffective for exercise soreness and chemotherapy nausea. Rice bran is possibly effective for high cholesterol (dyslipidemia) but possibly ineffective for colorectal cancer prevention.

Fennel is possibly effective for menstrual cramps. Sea buckthorn (listed as buckthorn) is possibly effective for burns.

For most other uses—including digestive support, general bowel health, and the conditions many colon cleanses target—the evidence we hold is insufficient or not established. Red raspberry, alfalfa, wheat grass, and cascara sagrada lack sufficient evidence to rate their effectiveness for the purposes claimed on this product.

The evidence, ingredient by ingredient Rice Bran Alfalfa Fennel Cascara Sagrada Rhubarb Ginger Red Raspberry Couch Grass

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 8 of the 9 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 9 of 9.
  • General safety write-ups exist for 9 of 9.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Taken short-term and at typical doses, the ingredients are generally well tolerated, though some carry real cautions. Rice bran may cause transient abdominal discomfort, flatulence, and erratic bowel habits, especially when you first increase your bran intake.

Alfalfa can cause abdominal discomfort, diarrhea, and flatulence; rare serious cases of lupus-like syndrome have been reported with chronic use. Cascara sagrada and rhubarb are stimulant laxatives and should not be used long-term—prolonged use can lead to electrolyte loss (especially potassium), dehydration, and kidney damage.

Fennel and ginger may cause gastrointestinal discomfort in some people. Red raspberry leaf is generally well tolerated but may cause diarrhea and abdominal upset.

Allergic reactions (including anaphylaxis) are rare but possible with rice bran, fennel, and rhubarb. Pregnancy: alfalfa is possibly unsafe; fennel is possibly unsafe; cascara sagrada and rhubarb are possibly unsafe; wheat grass should be avoided.

Ginger is likely safe or possibly safe, and red raspberry leaf is likely safe or possibly safe in pregnancy—but check with your doctor. Lactation: fennel, cascara sagrada, and rhubarb should be avoided; ginger is likely safe; red raspberry leaf safety data are limited; alfalfa and wheat grass safety data are insufficient.

Side effects, ingredient by ingredient Rice Bran Alfalfa Fennel Cascara Sagrada Rhubarb Ginger Red Raspberry Couch Grass

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

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

Why this rating?
  • 7 of the 9 matched ingredients can interact with medications — Alfalfa, Rhubarb, Red Raspberry, Fennel, Sea Buckthorn, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications.
  • For scale: 1,511 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check with your pharmacist if you take warfarin or other blood thinners (anticoagulants) or antiplatelet drugs—alfalfa, fennel, ginger, and red raspberry all carry Moderate or higher interaction risk. Also check if you take birth control pills or hormone replacement therapy (fennel and alfalfa can interfere), diabetes medications (alfalfa, ginger, and red raspberry may lower blood sugar), corticosteroids or diuretics (cascara sagrada and rhubarb increase low-potassium risk), digoxin or other heart medications (cascara sagrada and rhubarb affect potassium), or immunosuppressants like cyclosporine (alfalfa and rhubarb may reduce effectiveness).

Ciprofloxacin users should also check before starting, as fennel may reduce its absorption.

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

This is a multi-ingredient colon cleanser with a long history of traditional use, but the evidence for its effectiveness is incomplete, and it carries significant drug interaction risk—especially if you take blood thinners, birth control, diabetes medications, heart drugs, or immunosuppressants. The stimulant laxative ingredients (cascara sagrada and rhubarb) work short-term but shouldn't be used long-term without medical supervision.

If you're pregnant, nursing, or take any regular medications, talk with your pharmacist or doctor before starting.

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

Assessment coverage: 9 of 11 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 24, 2019.

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 Colon Cleanse, straight from the product label.

Brand 21st Century
Barcode (UPC) 740985228463
Net contents 120 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Sep 24, 2019
DSLD ID 206560
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), 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 Colon Cleanse by 21st Century, 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:
4 Vegetarian Capsule(s)
Maximum serving Sizes:
4 Vegetarian Capsule(s)
Servings per container
30
UPC/BARCODE
740985228463
IngredientAmount% DV
Proprietary Blend2000 mg--
Rice Bran0 NP--
Alfalfa0 NP--
Fennel0 NP--
Cascara Sagrada0 NP--
Rhubarb0 NP--
Psyllium0 NP--
Bentonite0 NP--
Ginger0 NP--
Red Raspberry0 NP--
Wheat Grass0 NP--
Buckthorn0 NP--

Other ingredients: Cellulose, Oat Fiber, Magnesium Stearate

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

Colon Cleanse is a combination of natural herbs to help cleanse your digestive system and support colon health.

Individual results may vary.

Herbal Digestive Aid Support

Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement, adults take four (4) vegetarian capsules at bedtime, or as directed by a healthcare provider. Do not exceed recommended dosage.

Precautions

Do not exceed recommended dosage.

Warning: Do not use if you have or develop diarrhea, loose stools, or abdominal pain. Some ingredients may worsen these conditions and may be harmful to your health.

Warning: Consult a healthcare provider prior to use if pregnant, nursing, on medications, have a medical condition or are planning a medical procedure.

Stop use and contact a physician if adverse reactions occur.

Keep out of reach of children.

Do not use if product appears to be tampered with or seal is broken.

Contains wheat ingredients.

Storage

Store at room temperature.

Formulation

No added Sugar, Salt, Preservatives, Artificial Flavors or Colors. Gluten Free.

Gluten free

FDA Disclaimer Statement

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

FDA Statement of Identity

Dietary Supplement

Seals/Symbols

Gluten free

Guaranteed quality Laboratory tested

Formula

Contains wheat ingredients.

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

See for yourself

Colon Cleanse by 21st Century label

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

Colon Cleanse 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 Colon Cleanse by 21st Century

These are the 11 active ingredients this product is made of. Select any to open its full monograph.

Serving size4 Vegetarian Capsule(s) Dosage formCapsule Servings per container30 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Proprietary Blend

2000 mg per serving

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

Interaction report

Colon Cleanse by 21st Century Drug Interactions

Want to check YOUR meds against Colon Cleanse?

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
1,510Drugs
2 Major 1,455 Moderate 53 Minor

Ingredients driving the most interactions

Ginger 1,007
Cascara Sagrada 745
Fennel 740
Rhubarb 658
Alfalfa 583

Individual Drug Interactions

The ingredients in Colon Cleanse interact with 1,510 drugs. Click any drug to see the details.

7 of the 11 ingredients in Colon Cleanse interact with drugs. Each result below shows which ingredient is responsible. Ginger Cascara Sagrada Fennel Rhubarb Alfalfa Buckthorn Red Raspberry

Each ingredient & the kinds of drugs it affects

For each ingredient in Colon Cleanse 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.

Ginger14 drug types · 1,007 drugs

Anticoagulant/Antiplatelet Drugs

Ginger may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs. However, research is conflicting.
Laboratory research suggests that ginger inhibits thromboxane synthetase and decreases platelet aggregation. However, this has not been demonstrated unequivocally in humans, with mixed results from clinical trials. Theoretically, excessive amounts of ginger might increase the risk of bleeding when used with anticoagulant/antiplatelet drugs.

Likelihood Possible Evidence B
Antidiabetes Drugs

Theoretically, taking ginger with antidiabetes drugs might increase the risk of hypoglycemia.
Animal and human research suggests that ginger might increase insulin levels and/or decrease blood glucose levels.

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

Ginger might increase or decrease the levels of CYP3A4 substrates.
In vitro research and some case reports suggest that ginger inhibits CYP3A4 activity. Three case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are CYP3A4 substrates (imatinib, dabrafenib, and crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration.
Conversely, other in vitro research suggests that ginger induces CYP3A4 activity, leading to reduced levels of CYP3A4 substrates. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Losartan (Cozaar)

Theoretically, ginger might increase levels of losartan and the risk of hypotension.
In animal research, ginger increased the levels and hypotensive effects of a single dose of losartan. It is not clear if ginger alters the concentration or effects of losartan when taken continuously. Additionally, this interaction has not been shown in humans.

Likelihood Possible Evidence D
Nifedipine (Procardia)

Ginger may have antiplatelet effects and increase the risk of bleeding if used with nifedipine.
Clinical research shows that combined treatment with ginger 1 gram plus nifedipine 10 mg significantly inhibits platelet aggregation when compared to nifedipine or ginger alone.

Likelihood Possible Evidence B
P-Glycoprotein Substrates

Ginger might increase the absorption and blood levels of P-glycoprotein (P-gp) substrates.
In vitro research and case reports suggest that ginger inhibits drug efflux by P-gp, potentially increasing absorption and serum levels of P-gp substrates. Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are P-gp substrates (trametinib, crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration.

Likelihood Possible Evidence D
Phenprocoumon (Marcoumar, Others)

Ginger might increase the risk of bleeding with phenprocoumon.
Phenprocoumon, a warfarin-related anticoagulant, might increase the international normalized ratio (INR) when taken with ginger. There is one case report of a 76-year-old woman with a stable INR on phenprocoumon that increased to greater than 10 when she began consuming dried ginger and ginger tea.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Ginger might increase the risk of bleeding with warfarin.
Laboratory research suggests that ginger might inhibit thromboxane synthetase and decrease platelet aggregation. In one case report, ginger increased the INR when taken with phenprocoumon, which has similar pharmacological effects as warfarin. In another case report, ginger increased the INR when taken with a combination of warfarin, hydrochlorothiazide, and acetaminophen. A longitudinal analysis suggests that taking ginger increases the risk of bleeding in patients taking warfarin for at least 4 months. However, research in healthy people suggests that ginger has no effect on INR, or the pharmacokinetics or pharmacodynamics of warfarin. Until more is known, monitor INRs closely in patients taking large amounts of ginger.

Likelihood Possible Evidence B
Calcium Channel Blockers

Theoretically, taking ginger with calcium channel blockers might increase the risk of hypotension.
Some animal and in vitro research suggests that ginger has hypotensive and calcium channel-blocking effects. Another animal study shows that concomitant administration of ginger and the calcium channel blocker amlodipine leads to greater reductions in blood pressure when compared with amlodipine alone.

Likelihood Unlikely Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, when taken prior to cyclosporine, ginger might decrease cyclosporine levels.
In an animal model, ginger juice taken 2 hours prior to cyclosporine administration reduced the maximum concentration and area under the curve of cyclosporine by 51% and 40%, respectively. This effect was not observed when ginger juice and cyclosporine were administered at the same time.

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

Theoretically, ginger might increase the levels of CYP1A2 substrates.
In vitro research shows that ginger inhibits CYP1A2 activity. However, this interaction has not been reported in humans.

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

Theoretically, ginger might increase the levels of CYP2B6 substrates.
In vitro research shows that ginger inhibits CYP2B6 activity. However, this interaction has not been reported in humans.

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

Theoretically, ginger might increase the levels of CYP2C9 substrates.
In vitro research shows that ginger inhibits CYP2C9 activity. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Metronidazole (Flagyl)

Theoretically, ginger might increase levels of metronidazole.
In an animal model, ginger increased the absorption and plasma half-life of metronidazole. In addition, the elimination rate and clearance of metronidazole was significantly reduced.

Likelihood Possible Evidence D
Ginger full monograph & interactions

Cascara Sagrada6 drug types · 745 drugs

Corticosteroids

Theoretically, cascara sagrada might increase the risk of hypokalemia when taken with corticosteroids.
Cascara sagrada has stimulant laxative effects, and long-term use has been associated with hypokalemia.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, cascara sagrada might cause hypokalemia, potentially increasing the risk of digoxin toxicity.
Cascara sagrada has stimulant laxative effects, and long-term use has been associated with hypokalemia.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, cascara sagrada might increase the risk of hypokalemia when taken with diuretic drugs.
Cascara sagrada has stimulant laxative effects, and long-term use has been associated with hypokalemia.

Likelihood Possible Evidence D
Stimulant Laxatives

Theoretically, cascara sagrada might have additive adverse effects when taken with stimulant laxatives.
Cascara sagrada has stimulant laxative effects and might compound fluid and electrolyte losses when taken with stimulant laxatives.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, cascara sagrada might increase the risk of bleeding when taken with warfarin.
Cascara sagrada has stimulant laxative effects. In some people, cascara sagrada can cause diarrhea. Diarrhea can increase the effects of warfarin, increase international normalized ratio (INR), and increase the risk of bleeding.

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

Theoretically, cascara sagrada might decrease the effects of CYP3A4 substrates.
In vitro research suggests that cascara sagrada can induce CYP3A4 enzymes, albeit to a much lower degree than rifampin, a known CYP3A4 inducer.

Likelihood Possible Evidence D
Cascara Sagrada full monograph & interactions

Fennel6 drug types · 740 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, fennel might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.

Animal research suggests that fennel oil has antithrombotic and antiplatelet effects.

Likelihood Possible Evidence D
Ciprofloxacin (Cipro)

Theoretically, fennel might decrease the levels and clinical effects of ciprofloxacin.

Animal research shows that fennel reduces ciprofloxacin bioavailability by nearly 50%, possibly due to the metal cations such as calcium, iron, and magnesium contained in fennel. This study also found that fennel increased tissue distribution and slowed elimination of ciprofloxacin.

Likelihood Probable Evidence D
Contraceptive Drugs

Theoretically, taking large amounts of fennel might decrease the effects of contraceptive drugs due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

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

Theoretically, fennel might increase levels of drugs metabolized by CYP3A4.

In vitro research suggests that fennel inhibits CYP3A4 enzyme activity. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, taking large amounts of fennel might interfere with hormone replacement therapy due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, taking large amounts of fennel might decrease the antiestrogenic effect of tamoxifen.

Some constituents of fennel have estrogenic activity, which may interfere with the antiestrogenic activity of tamoxifen.

Likelihood Possible Evidence D
Fennel full monograph & interactions

Rhubarb8 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
Rhubarb full monograph & interactions

Alfalfa6 drug types · 583 drugs

Warfarin (Coumadin)

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

Likelihood Probable Evidence D
Antidiabetes Drugs

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

Likelihood Possible Evidence D
Contraceptive Drugs

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

Likelihood Possible Evidence D
Estrogens

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

Likelihood Possible Evidence D
Immunosuppressants

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

Likelihood Possible Evidence D
Photosensitizing Drugs

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

Likelihood Possible Evidence D
Alfalfa full monograph & interactions

Buckthorn2 drug types · 289 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, sea buckthorn may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Clinical research suggests that sea buckthorn fruit extracts can inhibit platelet aggregation and adhesion to collagen and fibrinogen.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, taking sea buckthorn with antihypertensive drugs might increase the risk of hypotension.
Taking sea buckthorn appears to reduce blood pressure in some patients.

Likelihood Possible Evidence D
Buckthorn full monograph & interactions

Red Raspberry2 drug types · 135 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, taking red raspberry leaf with anticoagulant/antiplatelet drugs might increase the risk of bleeding.
In vitro research suggests that red raspberry leaf extract has antiplatelet activity and enhances the in vitro effects of the antiplatelet medication cangrelor. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Insulin

Red raspberry leaf might reduce glucose levels in patients being treated with insulin.
In one case report, a 38-year-old patient with gestational diabetes, whose blood glucose was being controlled with medical nutrition therapy and insulin, developed hypoglycemia after consuming two servings of raspberry leaf tea daily for 3 days beginning at 32 weeks' gestation. The patient required an insulin dose reduction. The hypoglycemia was considered to be probably related to use of red raspberry leaf tea.

Likelihood Possible Evidence D
Red Raspberry full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Colon Cleanse, from the product label.

21st Century

See all 21st Century products
Name
21st Century HealthCare, Inc.
Street Address
2119 S. Wilson St.
City
Tempe
State
AZ
ZipCode
85282
Web Address
www.21stcenturyvitamins.com
Pharmacist Counseling Corner

Colon Cleanse by 21st Century: Common Questions

Does Colon Cleanse by 21st Century interact with any medications?
Yes. Based on its ingredients, Colon Cleanse has a known interaction with 1,510 medications, including 2 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Colon Cleanse contains 11 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is it safe to take this while pregnant?
Several ingredients carry possibly unsafe or insufficient safety ratings in pregnancy: alfalfa, fennel, cascara sagrada, and rhubarb should be avoided. Ginger and red raspberry leaf have more favorable safety profiles in pregnancy, but safety is not fully established for all doses. Talk with your doctor or pharmacist before taking any supplement during pregnancy—they can advise you on what's right for your situation.
What's cascara sagrada in here for?
Cascara sagrada is a stimulant laxative—it's meant to promote bowel movements. It works, but it's designed for short-term use only. Long-term use can cause electrolyte loss, dehydration, and kidney problems, so don't use it regularly without a doctor's say-so.
Will this actually help my digestion?
The ingredients have mixed evidence. Ginger is possibly effective for nausea, and rhubarb has some evidence for certain digestive conditions, but for general digestive health or 'colon cleansing,' the evidence we hold is incomplete or insufficient. Talk with your doctor about what you're hoping to improve—they can advise whether this product is right for you.
Can I take this if I'm on blood thinners?
No—not without checking with your pharmacist first. Alfalfa, fennel, ginger, and red raspberry leaf all carry documented interactions with blood thinners like warfarin, and the risk of bleeding is real. Always verify with your pharmacist before adding any supplement to blood thinner therapy.
What are the most common side effects?
Abdominal discomfort, cramps, diarrhea, flatulence, and nausea are the most common. These often happen when you first increase fiber and stimulant laxative intake. If they don't ease up in a few days, or if you develop severe cramping, stop and talk with your pharmacist.
Is bentonite safe?
We don't hold interaction or safety data for bentonite, so we can't tell you what we know about it. If you have concerns about this ingredient, ask your pharmacist—they can look up additional safety information for you.

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.

Colon Cleanse label
Go deeper

The Full Monographs Behind Colon Cleanse’s Ingredients

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

Herb & supplement monograph

Rice Bran

Rice bran is the nutrient-rich outer layer of the rice grain and is a good source of fiber, healthy fats, and plant compounds. It is most studied for helping lower cholesterol, but for most...

Read the full Rice Bran monograph → Herb & supplement monograph

Alfalfa

Interacts with 583 drugs

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

Read the full Alfalfa monograph → Herb & supplement monograph

Fennel

Interacts with 740 drugs

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some small studies suggest possible benefit for...

Read the full Fennel monograph → Herb & supplement monograph

Cascara Sagrada

Interacts with 745 drugs

Cascara sagrada is a stimulant laxative made from the aged bark of a Pacific Northwest tree, used mainly for short-term relief of constipation. Because it can cause cramping, dehydration, an...

Read the full Cascara Sagrada monograph → Herb & supplement monograph

Rhubarb

Interacts with 658 drugs

Rhubarb root has a long history of use as a laxative and in traditional Chinese medicine, and its edible stalks are a common food. Most medicinal claims are backed by limited or low-quality...

Read the full Rhubarb monograph → Herb & supplement monograph

Ginger

Interacts with 1,007 drugs

Ginger is a widely used culinary spice with a long history in traditional medicine, and it has the strongest evidence for helping with nausea and vomiting, including from motion sickness, pr...

Read the full Ginger monograph → Herb & supplement monograph

Red Raspberry

Interacts with 135 drugs

Red raspberry leaf is a traditional herbal remedy most often used as a tea in late pregnancy and for menstrual discomfort, but solid scientific evidence for these uses is limited. It is gene...

Read the full Red Raspberry monograph → Herb & supplement monograph

Couch Grass

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

Read the full Couch Grass monograph → Herb & supplement monograph

Sea Buckthorn

Interacts with 289 drugs

Sea buckthorn is a berry-bearing shrub rich in vitamins, carotenoids, and fatty acids that people use for skin, eye, digestive, and heart health. Early research is promising for a few uses l...

Read the full Sea Buckthorn monograph →
Sources

Sources & How We Checked

Colon Cleanse'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 164 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.

Rice Bran 7 references
  1. Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
  2. Fujiwaki T, Furusho K. The effects of rice bran broth bathing in patients with atopic dermatitis. Acta Paediatr Jpn 1992;34:505-10.
  3. Uenotsuchi T, Satoh E, Kiryu H, Yano Y. Pyemotes dermatitis caused by indirect contact with husk rice. Br J Dermatol 2000;143:680-2. DOI
  4. Satoh R, Tsuge I, Tokuda R, Teshima R. Analysis of the distribution of rice allergens in brown rice grains and of the allergenicity of products containing rice bran. Food Chem. 2019;276:761-767. PubMed
  5. Togashi Y, Inomata N, Suzuki A, Hakuta A, Aihara M. Pediatric case with rice bran allergy induced by epicutaneous sensitization in a family rice shop. Allergol Int. 2019;68(1):117-118. PubMed
  6. So WKW, Chan JYW, Law BMH, et al. Effects of a Rice Bran Dietary Intervention on the Composition of the Intestinal Microbiota of Adults with a High Risk of Colorectal Cancer: A Pilot Randomised-Controlled Trial. Nutrients 2021;13(2):526. PubMed
  7. Haneda Y, Kadowaki S, Furui M, Taketani T. A pediatric case of food-dependent exercise-induced anaphylaxis due to rice bran. Asia Pac Allergy 2021;11(1):e4. PubMed

See these in context on the Rice Bran monograph →

Alfalfa 32 references
  1. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  2. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  3. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  4. Kurzer MS, Xu X. Dietary phytoestrogens. Annu Rev Nutr 1997;17:353-81. PubMed
  5. Farber JM, Carter AO, Varughese PV, et al. Listeriosis traced to the consumption of alfalfa tablets and soft cheese [Letter to the Editor]. N Engl J Med 1990;322:338. PubMed
  6. Molgaard J, von Schenck H, Olsson AG. Alfalfa seeds lower low density lipoprotein cholesterol and apolipoprotein B concentrations in patients with type II hyperlipoproteinemia. Atherosclerosis 1987;65:173-9. PubMed
  7. Light TD, Light JA. Acute renal transplant rejection possibly related to herbal medications. Am J Transplant 2003;3:1608-9. PubMed
  8. Prete PE. The mechanism of action of L-canavanine in inducing autoimmune phenomena. Arthritis Rheum 1985;28:1198-200. PubMed
  9. Alcocer-Varela J, Iglesias A, Llorente L, Alarcon-Segovia D. Effects of L-canavanine on T cells may explain the induction of systemic lupus erythematosus by alfalfa. Arthritis Rheum 1985;28:52-7. PubMed
  10. Roberts JL, Hayashi JA. Exacerbation of SLE associated with alfalfa ingestion. N Engl J Med 1983;308:1361. DOI
  11. Feingold, R. M. Should we fear "health foods"? Arch Intern Med 7-12-1999;159(13):1502. PubMed
  12. Taormina, P. J., Beuchat, L. R., and Slutsker, L. Infections associated with eating seed sprouts: an international concern. Emerg.Infect.Dis 1999;5(5):626-634. PubMed
  13. Backer, H. D., Mohle-Boetani, J. C., Werner, S. B., Abbott, S. L., Farrar, J., and Vugia, D. J. High incidence of extra-intestinal infections in a Salmonella Havana outbreak associated with alfalfa sprouts. Public Health Rep. 2000;115(4):339-345. PubMed
  14. Mohle-Boetani J, Werner B, Polumbo M, and et al. From the Centers for Disease Control and Prevention. Alfalfa sprouts-- Arizona, California, Colorado, and New Mexico, February-April, 2001. JAMA 2-6-2002;287(5):581-582.
  15. Howard, M. B. and Hutcheson, S. W. Growth dynamics of Salmonella enterica strains on alfalfa sprouts and in waste seed irrigation water. Appl.Environ.Microbiol. 2003;69(1):548-553.
  16. Winthrop, K. L., Palumbo, M. S., Farrar, J. A., Mohle-Boetani, J. C., Abbott, S., Beatty, M. E., Inami, G., and Werner, S. B. Alfalfa sprouts and Salmonella Kottbus infection: a multistate outbreak following inadequate seed disinfection with heat and chl
  17. Strapp, C. M., Shearer, A. E., and Joerger, R. D. Survey of retail alfalfa sprouts and mushrooms for the presence of Escherichia coil O157:H7, Salmonella, and Listeria with BAX, and evaluation of this polymerase chain reaction-based system with experimen
  18. Akaogi, J., Barker, T., Kuroda, Y., Nacionales, D. C., Yamasaki, Y., Stevens, B. R., Reeves, W. H., and Satoh, M. Role of non-protein amino acid L-canavanine in autoimmunity. Autoimmun.Rev 2006;5(6):429-435. PubMed
  19. Burden and causes of foodborne disease in Australia: Annual report of the OzFoodNet network, 2005. Commun.Dis Intell. 2006;30(3):278-300.
  20. Shemesh, M., Lindner, H. R., and Ayalon, N. Affinity of rabbit uterine oestradiol receptor for phyto-oestrogens and its use in a competitive protein-binding radioassay for plasma coumestrol. J Reprod.Fertil. 1972;29(1):1-9. PubMed
  21. Elakovich, S. D. and Hampton, J. M. Analysis of coumestrol, a phytoestrogen, in alfalfa tablets sold for human consumption. J Agric.Food Chem. 1984;32(1):173-175. PubMed
  22. Malinow, M. R., Bardana, E. J., Jr., Pirofsky, B., Craig, S., and McLaughlin, P. Systemic lupus erythematosus-like syndrome in monkeys fed alfalfa sprouts: role of a nonprotein amino acid. Science 4-23-1982;216(4544):415-417. PubMed
  23. Malinow, M. R., McLaughlin, P., and Stafford, C. Alfalfa seeds: effects on cholesterol metabolism. Experientia 5-15-1980;36(5):562-564. PubMed
  24. Farnsworth, N. R. Alfalfa pills and autoimmune diseases. Am J Clin Nutr. 1995;62(5):1026-1028. DOI
  25. Herbert, V. and Kasdan, T. S. Alfalfa, vitamin E, and autoimmune disorders. Am J Clin Nutr 1994;60(4):639-640.
  26. Mahon, B. E., Ponka, A., Hall, W. N., Komatsu, K., Dietrich, S. E., Siitonen, A., Cage, G., Hayes, P. S., Lambert-Fair, M. A., Bean, N. H., Griffin, P. M., and Slutsker, L. An international outbreak of Salmonella infections caused by alfalfa sprouts grow
  27. Gray, A. M. and Flatt, P. R. Pancreatic and extra-pancreatic effects of the traditional anti- diabetic plant, Medicago sativa (lucerne). Br J Nutr. 1997;78(2):325-334.
  28. Van Beneden, C. A., Keene, W. E., Strang, R. A., Werker, D. H., King, A. S., Mahon, B., Hedberg, K., Bell, A., Kelly, M. T., Balan, V. K., Mac Kenzie, W. R., and Fleming, D. Multinational outbreak of Salmonella enterica serotype Newport infections due to
  29. Rubenstein AH, Levin NW, and Elliott GA. Manganese-induced hypoglycemia. Lancet 1962;1348-1351.
  30. Kaufman W. Alfalfa seed dermatitis. JAMA 1954;155(12):1058-1059. PubMed
  31. Ponka A, Andersson Y, Siitonen A, and et al. Salmonella in alfalfa sprouts. Lancet 1995;345:462-463. PubMed
  32. Puschner B, Chen X, Read D, Affolter VK. Alfalfa hay induced primary photosensitization in horses. Vet J. 2016 May;211:32-8. PubMed

See these in context on the Alfalfa monograph →

Fennel 17 references
  1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Zhu M, Wong PY, Li RC. Effect of oral administration of fennel (Foeniculum vulgare) on ciprofloxacin absorption and disposition in the rat. J Pharm Pharmacol 1999;51:1391-6.
  4. Gral N, Beani JC, Bonnot D, et al. [Plasma levels of psoralens after celery ingestion]. Ann Dermatol Venereol 1993;120:599-603.
  5. Burkhard PR, Burkhardt K, Haenggeli CA, Landis T. Plant-induced seizures: reappearance of an old problem. J Neurol 1999;246:667-70. PubMed
  6. Rosti L, Nardini A, Bettinelli ME, Rosti D. Toxic effects of a herbal tea mixture in two newborns. Acta Paediatrica 1994;83:683. PubMed
  7. Cuzzolin L, Zaffani S, and Benoni G. Safety implications regarding use of phytomedicines. Eur.J Clin Pharmacol. 2006;62:37-42. PubMed
  8. Tognolini, M., Ballabeni, V., Bertoni, S., Bruni, R., Impicciatore, M., and Barocelli, E. Protective effect of Foeniculum vulgare essential oil and anethole in an experimental model of thrombosis. Pharmacol.Res 2007;56(3):254-260. PubMed
  9. Subehan, Usia, T., Iwata, H., Kadota, S., and Tezuka, Y. Mechanism-based inhibition of CYP3A4 and CYP2D6 by Indonesian medicinal plants. J Ethnopharmacol. 5-24-2006;105(3):449-455. PubMed
  10. Tognolini, M., Barocelli, E., Ballabeni, V., Bruni, R., Bianchi, A., Chiavarini, M., and Impicciatore, M. Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. Life Sci. 2-23-2006;78(13):1419-1432. PubMed
  11. Subehan, Zaidi, S. F., Kadota, S., and Tezuka, Y. Inhibition on human liver cytochrome P450 3A4 by constituents of fennel (Foeniculum vulgare): identification and characterization of a mechanism-based inactivator. J Agric.Food Chem. 12-12-2007;55(25):101 PubMed
  12. LEVY, S. B. Bronchial asthma due to ingestion of fennel and fennel seed. Ann.Allergy 1948;6(4):415.
  13. Ottolenghi, A., De Chiara, A., Arrigoni, S., Terracciano, L., and De Amici, M. [Diagnosis of food allergy caused by fruit and vegetables in children with atopic dermatitis]. Pediatr Med Chir 1995;17(6):525-530.
  14. Trabace L, Tucci P, Ciuffreda L, et al. "Natural" relief of pregnancy-related symptoms and neonatal outcomes: above all do no harm. J Ethnopharmacol. 2015;174:396-402. PubMed
  15. Denaxa D, Arkwright PD. Fennel as a cause of immediate hypersensitivity to toothpaste. Ann Allergy Asthma Immunol. 2020;125(1):99-100. PubMed
  16. Lee HW, Ang L, Lee MS, Alimoradi Z, Kim E. Fennel for reducing pain in primary dysmenorrhea: a systematic review and meta-analysis of randomized controlled trials. Nutrients 2020;12(11):3438. PubMed
  17. Mathew T, John SK, Javali M, Vasireddy M, Nadig R, Sarma GRK. Substance use related cluster headache: A case series. Headache 2022;62(7):908-910. PubMed

See these in context on the Fennel monograph →

Cascara Sagrada 9 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. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  3. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  4. Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
  5. Nusko G, Schneider B, Schneider I, et al. Anthranoid laxative use is not a risk factor for colorectal neoplasia: results of a prospective case control study. Gut 2000;46:651-5. PubMed
  6. Nadir A, Reddy D, Van Thiel DH. Cascara-sagrada induced intrahepatic cholestasis causing portal hypertension: case report and review of herbal hepatotoxicity. Am J Gastroenterol 2000;95:3634-7. PubMed
  7. Nakasone ES, Tokeshi J. A serendipitous find: a case of cholangiocarcinoma identified incidentally after acute liver injury due to cascara sagrada ingestion. Hawaii J Med Public Health 2015;74(6):200-2.
  8. Cirillo C, Capasso R. Constipation and botanical medicines: an overview. Phytother Res 2015;29(10):1488-93. PubMed
  9. Mazzari ALDA, Lacerda MG, Milton FA, et al. In vitro effects of European and Latin-American medicinal plants in CYP3A4 gene expression, glutathione levels, and P-glycoprotein activity. Front Pharmacol 2022;13:826395. PubMed

See these in context on the Cascara Sagrada monograph →

Rhubarb 20 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. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  4. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  5. Nusko G, Schneider B, Schneider I, et al. Anthranoid laxative use is not a risk factor for colorectal neoplasia: results of a prospective case control study. Gut 2000;46:651-5. PubMed
  6. Kwan TH, Tong MK, Leung KT, et al. Acute renal failure associated with prolonged intake of slimming pills containing anthraquinones. Hong Kong Med J 2006;12:394-7.
  7. Fairbairn JW. The anthraquinone laxatives. Biological assay and its relation to chemical structure. Pharmacology 1976;14:48-61. PubMed
  8. Siegers, C. P., Hertzberg-Lottin, E., Otte, M., and Schneider, B. Anthranoid laxative abuse--a risk for colorectal cancer? Gut 1993;34(8):1099-1101. PubMed
  9. Fan, J. G. Evaluating the efficacy and safety of Danning Pian in the short-term treatment of patients with non-alcoholic fatty liver disease: a multicenter clinical trial. Hepatobiliary.Pancreat.Dis.Int 2004;3(3):375-380.
  10. Yan, M., Zhang, L. Y., Sun, L. X., Jiang, Z. Z., and Xiao, X. H. Nephrotoxicity study of total rhubarb anthraquinones on Sprague Dawley rats using DNA microarrays. J Ethnopharmacol. 4-15-2006; PubMed
  11. Zhang, J. H., Li, L. S., and Zhang, M. Clinical effects of rheum and captopril on preventing progression of chronic renal failure. Chin Med J (Engl.) 1990;103(10):788-793.
  12. Mitsuma, T., Yokozawa, T., Oura, H., and Terasawa, K. [Rhubarb therapy in patients with chronic renal failure (Part 2)]. Nippon Jinzo Gakkai Shi 1987;29(2):195-207.
  13. Wu, C. X. [A preliminary study on the effect of a single Rheum officinale in heavy doses in the treatment of acute icteric hepatitis]. Zhong.Xi.Yi.Jie.He.Za Zhi.(Chinese Journal of Modern Developments in Traditional Medicine) 1984;4(2):88-89.
  14. Jiao, D. H. [Clinical research on the hemostatic effect of rhubarb on peptic ulcer with acute bleeding]. Zhong.Xi.Yi.Jie.He.Za Zhi.(Chinese Journal of Modern Developments in Traditional Medicine) 1984;4(10):597-600, 579.
  15. Jiao, D. H., Ma, Y. H., Chen, S. J., Liu, C. T., Shu, H. N., and Chu, C. M. Resume of 400 cases of acute upper digestive tract bleeding treated by rhubarb alone. Pharmacology 1980;20 Suppl 1:128-130.
  16. Zhang, JH, Yao, XD, Song, Y, and et al. [Long-term treating effects of rhubarb and captopril in delaying the progression of renal failure]. Chinese Kidney Disease Journal 1993;9(4):197-201.
  17. Rehman H, Begum W, Anjum F, Tabasum H, Zahid S. Effect of rhubarb (Rheum emodi) in primary dysmenorrhoea: a single-blind randomized controlled trial. J Complement Integr Med. 2015 Mar;12(1):61-9.
  18. Yu CP, Lin HJ, Lin SP, Shia CS, Chang PH, Hou YC, Hsieh YW. Rhubarb decreased the systemic exposure of cyclosporine, a probe substrate of P-glycoprotein and CYP 3A. Xenobiotica. 2016 Aug;46(8):677-82. PubMed
  19. Byeon JH, Kil JH, Ahn YC, Son CG. Systematic review of published data on herb induced liver injury. J Ethnopharmacol 2019;233:190-6. PubMed
  20. Zhao D, Feng SX, Zhang HJ, et al. Pharmacokinetics, tissue distribution and excretion of five rhubarb anthraquinones in rats after oral administration of effective fraction of anthraquinones from rheum officinale. Xenobiotica. 2021;51(8):916-925. PubMed

See these in context on the Rhubarb monograph →

Ginger 64 references
  1. Fischer-Rasmussen W, Kjaer SK, Dahl C, Asping U. Ginger treatment of hyperemesis gravidarum. Eur J Obstet Gynecol Reprod Biol 1991;38:19-24. PubMed
  2. Jewell D, Young G. Interventions for nausea and vomiting in early pregnancy. Cochrane Database Syst Rev 2000;(2):CD000145. PubMed
  3. Vutyavanich T, Kraisarin T, Ruangsri R. Ginger for nausea and vomiting in pregnancy: randomized, double-masked, placebo-controlled trial. Obstet Gynecol 2001;97:577-82. DOI
  4. Backon J. Ginger in preventing nausea and vomiting of pregnancy; a caveat due to its thromboxane synthetase activity and effect on testosterone binding. Eur J Obstet Gynecol Reprod Biol 1991;42:163-4. PubMed
  5. Srivastava KC. Effect of onion and ginger consumption on platelet thromboxane production in humans. Prostaglandins Leukot Essent Fatty Acids 1989;35:183-5. PubMed
  6. Stewart JJ, Wood MJ, Wood CD, Mims ME. Effects of ginger on motion sickness susceptibility and gastric function. Pharmacology 1991;42:111-20. PubMed
  7. Smith C, Crowther C, Willson K, et al. A randomized controlled trial of ginger to treat nausea and vomiting in pregnancy. Obstet Gynecol 2004;103:639-45. PubMed
  8. Portnoi G, Chng LA, Karimi-Tabesh L, et al. Prospective comparative study of the safety and effectiveness of ginger for the treatment of nausea and vomiting in pregnancy. Am J Obstet Gynecol 2003;189:1374-7.. PubMed
  9. Wigler I, Grotto I, Caspi D, Yaron M. The effects of Zintona EC (a ginger extract) on symptomatic gonarthritis. Osteoarthritis Cartilage 2003;11:783-9. PubMed
  10. Ghayur MN, Gilani AH. Ginger lowers blood pressure through blockade of voltage-dependent calcium channels. J Cardiovasc Pharmacol 2005;45:74-80. PubMed
  11. Thomson M, Al-Qattan KK, Al-Sawan SM, et al. The use of ginger (Zingiber officinale Rosc.) as a potential anti-inflammatory and antithrombotic agent. Prostaglandins Leukot Essent Fatty Acids 2002;67:475-8. PubMed
  12. Kanerva L, Estlander T, Jolanki R. Occupational allergic contact dermatitis from spices. Contact Dermatitis 1996;35:157-62. PubMed
  13. Akhani SP, Vishwakarma SL, Goyal RK. Anti-diabetic activity of Zingiber officinale in streptozotocin-induced type I diabetic rats. J Pharm Pharmacol 2004;56:101-5.
  14. Kruth P, Brosi E, Fux R, et al. Ginger-associated overanticoagulation by phenprocoumon. Ann Pharmacother 2004;38:257-60. PubMed
  15. Jiang X, Williams KM, Liauw WS, et al. Effect of ginkgo and ginger on the pharmacokinetics and pharmacodynamics of warfarin in healthy subjects. Br J Clin Pharmacol 2005;59:425-32. PubMed
  16. Borrelli F, Capasso R, Aviello G, et al. Effectiveness and safety of ginger in the treatment of pregnancy-induced nausea and vomiting. Obstet Gynecol 2005;105:849-56. PubMed
  17. Smith C, Crowther C, Wilson K et al. A randomized controlled trial of ginger to treat nausea and vomiting in pregnancy. Obstet Gynecol 2004;103:639-45. PubMed
  18. Jiang X, Blair EY, McLachlan AJ. Investigation of the effects of herbal medicines on warfarin response in healthy subjects: a population pharmacokinetic-pharmacodynamic modeling approach. J Clin Pharmacol 2006;46:1370-8. PubMed
  19. Chittumma P, Kaewkiattikun K, Wiriyasiriwach B. Comparison of the effectiveness of ginger and vitamin B6 for treatment of nausea and vomiting in early pregnancy: a randomized double-blind controlled trial. J Med Assoc Thai 2007;90:15-20.
  20. Ozgoli G, Goli M, Moattar F. Comparison of effects of ginger, mefenamic acid, and ibuprofen on pain in women with primary dysmenorrhea. J Altern Complement Med 2009;15:129-32. PubMed
  21. Black CD, Herring MP, Hurley DJ, O'Connor PJ. Ginger (Zingiber officinale) reduces muscle pain caused by eccentric exercise. J Pain 2010;11:894-903. PubMed
  22. Heitmann K, Nordeng H, Holst L. Safety of ginger use in pregnancy: results from a large population-based cohort study. Eur J Clin Pharmacol 2012 Jun 17. PubMed
  23. Ryan JL, Heckler CE, Roscoe JA, et al. Ginger (Zingiber officinale) reduces acute chemotherapy-induced nausea: a URCC CCOP study of 576 patients. Support Care Cancer. 2012;20:1479-89. PubMed
  24. Backon J. Ginger as an antiemetic: possible side effects due to its thromboxane synthetase activity. Anaesthesia. 1991;46(8):705-6.. PubMed
  25. Abebe W. Herbal medication: potential for adverse interactions with analgesic drugs. J Clin Pharm Ther. 2002;27:391-401. PubMed
  26. Argento A, Tiraferri E, Marzaloni M. [Oral anticoagulants and medicinal plants. An emerging interaction]. Ann Ital Med Int. 2000;15:139-43.
  27. Young HY, Liao JC, Chang YS, et al. Synergistic effect of ginger and nifedipine on human platelet aggregation: a study in hypertensive patients and normal volunteers. Am J Chin Med. 2006;34:545-51. PubMed
  28. Greenway FL, Liu Z, Martin CK, et al. Safety and efficacy of NT, an herbal supplement, in treating human obesity. Int J Obes (Lond). 2006;30:1737-41. PubMed
  29. Shalansky S, Lynd L, Richardson K, et al. Risk of warfarin-related bleeding events and supratherapeutic international normalized ratios associated with complementary and alternative medicine: a longitudinal analysis. Pharmacotherapy. 2007;27:1237-47. PubMed
  30. Lesho EP, Saullo L, Udvari-Nagy S. A 76-year-old woman with erratic anticoagulation. Cleve Clin J Med. 2004;71:651-6. PubMed
  31. Okonta JM, Uboh M, Obonga WO. Herb-Drug Interaction: A Case Study of Effect of Ginger on the Pharmacokinetic of Metronidazole in Rabbit. Indian Journal of Pharmaceutical Sciences (India) 2008;70(230):232. PubMed
  32. Chiang HM, Chao PD, Hsiu SL, et al. Ginger significantly decreased the oral bioavailability of cyclosporine in rats. Am J Chin Med. 2006;34:845-55. PubMed
  33. Bhandari U, Kanojia R, Pillai KK. Effect of ethanolic extract of Zingiber officinale on dyslipidaemia in diabetic rats. J Ethnopharmacol. 2005;97:227-30. PubMed
  34. Ojewole JA. Analgesic, antiinflammatory and hypoglycaemic effects of ethanol extract of Zingiber officinale (Roscoe) rhizomes (Zingiberaceae) in mice and rats. Phytother Res. 2006;20:764-72.
  35. Al-Amin ZM, Thomson M, Al-Qattan KK, et al. Anti-diabetic and hypolipidaemic properties of ginger (Zingiber officinale) in streptozotocin-induced diabetic rats. Br J Nutr. 2006;96:660-6.
  36. Islam MS, Choi H. Comparative effects of dietary ginger (Zingiber officinale) and garlic (Allium sativum) investigated in a type 2 diabetes model of rats. J Med Food. 2008;11:152-9.
  37. Cady RK, Goldstein J, Nett R, et al. A double-blind placebo-controlled pilot study of sublingual feverfew and ginger (LipiGesic M) in the treatment of migraine. Headache 2011;51:1078-86.
  38. Futrell, J. M. and Rietschel, R. L. Spice allergy evaluated by results of patch tests. Cutis 1993;52(5):288-290.
  39. Sripramote, M. and Lekhyananda, N. A randomized comparison of ginger and vitamin B6 in the treatment of nausea and vomiting of pregnancy. J Med Assoc.Thai. 2003;86(9):846-853.
  40. Lohsiriwat, S., Rukkiat, M., Chaikomin, R., and Leelakusolvong, S. Effect of ginger on lower esophageal sphincter pressure. J.Med.Assoc.Thai. 2010;93(3):366-372.
  41. Liu, P. H. and Ho, H. L. Ginger and drug bezoar induced small bowel obstruction. J R.Coll.Surg.Edinb. 1983;28(6):397-398.
  42. Maghbooli M, Golipour F, Moghimi Esfandabadi A, Yousefi M. Comparison between the efficacy of ginger and sumatriptan in the ablative treatment of the common migraine. Phytother Res 2014;28(3):412-5. PubMed
  43. Mahluji S, Attari VE, Mobasseri M, Payahoo L, Ostadrahimi A, Golzari SE. Effects of ginger (Zingiber officinale) on plasma glucose level, HbA1c and insulin sensitivity in type 2 diabetic patients. Int J Food Sci Nutr 2013;64(6):682-6.
  44. Mozaffari-Khosravi H, Talaei B, Jalali BA, Najarzadeh A, Mozayan MR. The effect of ginger powder supplementation on insulin resistance and glycemic indices in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled trial. Complement PubMed
  45. Paramdeep G. Efficacy and tolerability of ginger (Zingiber officinale) in patients of osteoarthritis of knee. Indian J Physiol Pharmacol 2013;57(2):177-83.
  46. Rahnama P, Montazeri A, Huseini HF, Kianbakht S, Naseri M. Effect of Zingiber officinale R. rhizomes (ginger) on pain relief in primary dysmenorrhea: a placebo randomized trial. BMC Complement Altern Med 2012;12:92. PubMed
  47. Viljoen E, Visser J, Koen N, Musekiwa A. A systematic review and meta-analysis of the effect and safety of ginger in the treatment of pregnancy-associated nausea and vomiting. Nutr J 2014;13:20. PubMed
  48. Bartels EM, Folmer VN, Bliddal H, et al. Efficacy and safety of ginger in osteoarthritis patients: a meta-analysis of randomized placebo-controlled trials. Osteoarthritis Cartilage. 2015;23(1):13-21. PubMed
  49. Choi JS, Han JY, Ahn HK, et al. Assessment of fetal and neonatal outcomes in the offspring of women who had been treated with dried ginger (Zingiberis rhizoma siccus) for a variety of illnesses during pregnancy. J Obstet Gynaecol. 2015;35(2):125-30.
  50. Marx W, McKavanagh D, McCarthy AL, Bird R, Ried K, Chan A, Isenring L. The effect of ginger (Zingiber officinale) on platelet aggregation: A systematic literature review. PLoS One. 2015;10(10):e0141119. PubMed
  51. Crichton M, Marshall S, Marx W, McCarthy AL, Isenring E. Efficacy of ginger (Zingiber officinale) in ameliorating chemotherapy-induced nausea and vomiting and chemotherapy-related outcomes: A systematic review update and meta-analysis. J Acad Nutr Diet. 2 PubMed
  52. Martins LB, Rodrigues AMDS, Monteze NM, et al. Double-blind placebo-controlled randomized clinical trial of ginger (Zingiber officinale Rosc.) in the prophylactic treatment of migraine. Cephalalgia. 2020;40(1):88-95.
  53. Martins LB, Rodrigues AMDS, Rodrigues DF, Dos Santos LC, Teixeira AL, Ferreira AVM. Double-blind placebo-controlled randomized clinical trial of ginger (Zingiber officinale Rosc.) addition in migraine acute treatment. Cephalalgia. 2019;39(1):68-76.
  54. Ahad A, Raish M, Bin Jardan YA, Alam MA, Al-Mohizea AM, Al-Jenoobi FI. Effect of Hibiscus sabdariffa and Zingiber officinale on the antihypertensive activity and pharmacokinetic of losartan in hypertensive rats. Xenobiotica. 2020:1-11.
  55. Okuhira H, Nakatani Y, Furukawa F, Kanazawa N. Anaphylaxis to ginger induced by herbal medicine. Allergol Int. 2020;69(1):159-160. PubMed
  56. Yamprasert R, Chanvimalueng W, Mukkasombut N, Itharat A. Ginger extract versus Loratadine in the treatment of allergic rhinitis: a randomized controlled trial. BMC Complement Med Ther. 2020;20(1):116. PubMed
  57. Ebrahimzadeh A, Ebrahimzadeh A, Mirghazanfari SM, Hazrati E, Hadi S, Milajerdi A. The effect of ginger supplementation on metabolic profiles in patients with type 2 diabetes mellitus: a systematic review and meta-analysis of randomized controlled trials. PubMed
  58. Alam MA, Bin Jardan YA, Alzenaidy B, et al. Effect of Hibiscus sabdariffa and Zingiber officinale on pharmacokinetics and pharmacodynamics of amlodipine. J Pharm Pharmacol 2021;73(9):1151-60.
  59. Akbarzadeh E, Heydari M, Atarzadeh F, Jaladat AM. Chronic dysuria following ginger (Zingiber officinale) use: a case report. Galen Med J 2018;7:e1086. DOI
  60. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. PubMed
  61. Rostamkhani H, Veisi P, Niknafs B, Jafarabadi MA, Ghoreishi Z. The effect of zingiber officinale on prooxidant-antioxidant balance and glycemic control in diabetic patients with ESRD undergoing hemodialysis: a double-blind randomized control trial. BMC Co PubMed
  62. Husain I, Dale OR, Idrisi M, et al. Evaluation of the Herb-Drug Interaction (HDI) Potential of Zingiber officinale and Its Major Phytoconstituents. J Agric Food Chem. 2023;71(19):7521-7534.
  63. Committee on Practice Bulletins-Obstetrics. ACOG Practice Bulletin No. 189: Nausea And Vomiting Of Pregnancy. Obstet Gynecol. 2018;131(1):e15-e30. PubMed
  64. Pochet S, Lechon AS, Lescrainier C, et al. Herb-anticancer drug interactions in real life based on VigiBase, the WHO global database. Sci Rep 2022;12(1):14178. PubMed

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Red Raspberry 8 references
  1. Eagon PK, Elm MS, Hunter DS, et al. Medicinal herbs: modulation of estrogen action. Era of Hope Mtg, Dept Defense; Breast Cancer Res Prog, Atlanta, GA 2000;Jun 8-11.
  2. Parsons M, Simpson M, Ponton T. Raspberry leaf and its effects on labour: safety and efficacy. Aust Coll Midwives Inc J 1999;12:20-5.
  3. Simpson M, Parsons M, Greenwood J, Wade K. Raspberry leaf in pregnancy: its safety and efficacy in labor. J Midwifery Womens Health 2001;46:51-9.. PubMed
  4. Mullen W, McGinn J, Lean ME, et al. Ellagitannins, flavonoids, and other phenolics in red raspberries and their contribution to antioxidant capacity and vasorelaxation properties. J Agric Food Chem 2002;50:5191-6.. PubMed
  5. Sherson, D., Andersen, B., Hansen, I., and Kjoller, H. Occupational asthma due to freeze-dried raspberry. Ann Allergy Asthma Immunol. 2003;90(6):660-663. PubMed
  6. Cheang KI, Nguyen TT, Karjane NW, Salley KE. Raspberry Leaf and Hypoglycemia in Gestational Diabetes Mellitus. Obstet Gynecol. 2016;128(6):1421-4. PubMed
  7. Dudzinska D, Bednarska K, Boncler M, Luzak B, Watala C. The influence of Rubus idaeus and Rubus caesius leaf extracts on platelet aggregation in whole blood. Cross-talk of platelets and neutrophils. Platelets. 2016;27(5):433-9.
  8. Henrotin Y, Cozannet RL, Fança-Berthon P, et al. Rubus idaeus extract improves symptoms in knee osteoarthritis patients: results from a phase II double-blind randomized controlled trial. BMC Musculoskelet Disord 2022;23(1):650. PubMed

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Sea Buckthorn 7 references
  1. Johansson AK, Korte H, Yang B, et al. Sea buckthorn berry oil inhibits platelet aggregation. J Nutr Biochem 2000;11:491-5.. PubMed
  2. Grad, S. C., Muresan, I., and Dumitrascu, D. L. Generalized yellow skin caused by high intake of sea buckthorn. Forsch.Komplementmed. 2012;19(3):153-156. PubMed
  3. Vlasov, V. V. [Hippophae oil in the treatment of superficial skin burns]. Vestn.Dermatol Venerol. 1970;44(6):69-72.
  4. Chang BB, Wang F Xu TY Zhang QQ He J Zhang XJ Li J. Total flavones of Hippophae rhamnoides L. for essential hypertension: a systematic review of randomized controlled trials. Chinese Journal of Evidence-Based Medicine. 2009;9(11):1207-1213. DOI
  5. Olas B, Kontek B, Szczesna M, et al. Inhibition of blood platelet adhesion by phenolics rich fraction of Hippophae rhamnoides L. fruits. J Physiol Pharmacol. 2017;68(2):223-9.
  6. Larmo P, Järvinen R, Laihia J, et al. Effects of a sea buckthorn oil spray emulsion on dry eye. Cont Lens Anterior Eye. 2019;42(4):428-433. PubMed
  7. De Seta F, Caruso S, Di Lorenzo G, Romano F, Mirandola M, Nappi RE. Efficacy and safety of a new vaginal gel for the treatment of symptoms associated with vulvovaginal atrophy in postmenopausal women: A double-blind randomized placebo-controlled study. Ma PubMed

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Parts of this content are provided by the Therapeutic Research Center, LLC.

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

© 2021 Therapeutic Research Center, LLC

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