Major interaction on record — check this product against your medications before combining. Based on 10 of 12 ingredients. Check your meds →
Dietary supplement

Endefen Ingredients & Drug Interactions

by Metagenics

Endefen label
See full label image
Powder Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Endefen 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

Endefen is a dietary supplement by Metagenics with 12 active ingredients. Its ingredients are commonly taken for replacing fluids and electrolytes, preventing dehydration during exercise or illness, treating low blood sodium (under medical care).Based on those ingredients, 2,270 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Dietary Fiber, Green Tea Leaf Extract, Decaffeinated, Astaxanthin. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Endefen by Metagenics

Ask about any prescription or over-the-counter medication and we check it for interactions with Endefen by Metagenics — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Endefen by Metagenics

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 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 12 of its 12 active ingredients.
  • “Soy Lecithin” is listed as a grouped ingredient — the label gives one combined amount (500 mg) without saying how much of each component you get.
  • “Green Tea Leaf Extract, Decaffeinated” is listed as a grouped ingredient — the label gives one combined amount (125 mg) without saying how much of each component you get.

Endefen contains 11 active ingredients. Sodium is an essential mineral but present here at a level that warrants careful consideration if you're managing blood pressure or taking certain medications.

Vitamin C supports immune function and iron absorption. D-Mannose is a simple sugar studied for urinary tract health.

Astaxanthin is a red antioxidant from marine algae. Apple Powder provides polyphenols and fiber.

Chinese Cinnamon and Arabinogalactans (a soluble fiber from larch) are included for their traditional roles. The formula also contains Epigallocatechin Gallate and Catechins (antioxidants from green tea), along with Soy Lecithin and Plantain Powder.

Inactive ingredients—rice bran, xylitol, rice syrup solids, and natural flavors—are excipients that give the powder its texture and taste.

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: nutritionally support healthy gastrointestinal tract function.
  • We looked for evidence on: Aspirin-associated gastric damage, Crohn disease, Diarrhea, Dyspepsia, Leaky gut, Intestinal barrier function — and 2 related terms.
  • The closest evidence on file: Black Psyllium is rated "Insufficient Reliable Evidence To Rate" for Diarrhea (Natural Medicines).
  • Also on file: Apple is rated "Insufficient Reliable Evidence To Rate" for Diarrhea.
  • Also on file: Vitamin C is rated "Insufficient Reliable Evidence To Rate" for Aspirin-associated gastric damage.

The evidence for Endefen's active ingredients is mixed and mostly limited. Sodium is likely effective for cystic fibrosis support; vitamin C is effective for vitamin C deficiency and possibly effective for several other conditions including anemia and exercise-induced respiratory infections.

D-Mannose, however, is rated possibly ineffective for urinary tract infections—the condition many people take it for. Astaxanthin, Chinese Cinnamon, Arabinogalactans, and the antioxidants (catechins, EGCG) lack sufficient reliable evidence to rate their effectiveness for most claimed uses in our data.

Apple Powder shows insufficient evidence for the conditions it's studied for.

The evidence, ingredient by ingredient Sodium Vitamin C Black Psyllium Lecithin D-mannose Astaxanthin Apple Larch Arabinogalactan

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

Most ingredients in Endefen are generally well tolerated at typical doses. Sodium is safe in normal dietary amounts but should not be supplemented without medical oversight—excess intake is linked to high blood pressure and kidney stress.

Vitamin C is safe at normal doses but high doses (above 2 grams daily) can cause stomach upset, heartburn, diarrhea, and in people prone to kidney stones, stone formation. D-Mannose may cause bloating, diarrhea, or nausea in some people; long-term safety data are sparse.

Astaxanthin is well tolerated short-term but can cause loose stools, red-colored stool, or abdominal pain at higher doses; long-term safety is not well established. Chinese Cinnamon in large supplement amounts raises liver toxicity concerns due to coumarin content.

Arabinogalactans may cause bloating and flatulence as a fiber. Apple Powder is safe as a food but rare allergic reactions including anaphylaxis have been reported in those with Rosaceae fruit allergies.

For pregnancy and breastfeeding: Sodium is rated both likely safe and possibly unsafe (the data are mixed). Vitamin C is likely safe in typical amounts but possibly unsafe at high doses.

D-Mannose, astaxanthin, Arabic galactans, and Apple Powder lack sufficient data—talk with your doctor or pharmacist before use during pregnancy or breastfeeding.

Side effects, ingredient by ingredient Sodium Vitamin C Black Psyllium Lecithin D-mannose Astaxanthin Apple Larch Arabinogalactan

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 8 matched ingredients can interact with medications — Black Psyllium, Apple, Larch Arabinogalactan, Vitamin C, Cassia Cinnamon, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; cancer treatments; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 2,231 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 Endefen, double-check with your pharmacist if you're on heart and blood pressure medications—especially atenolol, aliskiren, or other blood pressure drugs—because Apple Powder can sharply reduce their absorption. Also flag lithium (Sodium and Apple Powder can alter its levels), blood thinners like warfarin (Vitamin C at high doses), antidiabetes drugs (Apple Powder and Chinese Cinnamon can lower blood sugar), oral contraceptives or hormone replacement therapy (Vitamin C can increase estrogen levels), immunosuppressants like cyclosporine (Arabinogalactans), and allergy medicines like fexofenadine (Apple Powder).

If you're on any prescription medication, search it below before you start.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.

Endefen is best approached with caution if you take heart medications (like atenolol or aliskiren), allergy medications (like fexofenadine), blood thinners, lithium, blood pressure drugs, or immunosuppressants. The sodium and apple powder in this formula create specific risks worth discussing with your pharmacist before starting.

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

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

Assessment coverage: 8 of 12 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 23, 2025.

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 Endefen, straight from the product label.

Brand Metagenics
Barcode (UPC) 755571015051
Net contents 14.81 Ounce(s); 420 Gram(s)
Market status On market
Date entered into DSLD Feb 23, 2025
DSLD ID 323351
Product type Other Combinations
Supplement form Powder
Dietary claims / uses Nutrient, 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 Endefen by Metagenics, 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:
7.5 Gram(s)
Maximum serving Sizes:
7.5 Gram(s)
Servings per container
56
UPC/BARCODE
755571015051
IngredientAmount% DV
Calories30 Calorie(s)--
Total Carbohydrates5 Gram(s)2%
Sodium5 mg1%
Vitamin C150 mg167%
Total Sugars1 Gram(s)--
Total Fat1 Gram(s)1%
Dietary Fiber2 Gram(s)7%
Protein1 Gram(s)--
Soy Lecithin500 mg--
D-Mannose125 mg--
Epigallocatechin Gallate50 mg--
Catechins75 mg--
Astaxanthin250 mcg--
Apple, Powder1 Gram(s)--
Arabinogalactans750 mg--
Chinese Cinnamon, Powder350 mg--
Plantain, Powder1 Gram(s)--
Phosphatides485 mg--
Green Tea Leaf Extract, Decaffeinated125 mg--

Other ingredients: Rice Bran, Xylitol, Rice Syrup, Solids, Natural Flavors

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.
Formulation

Endefen is uniquely designed to nutritionally support the healthy function of the gastrointestinal (GI) tract. This exceptional formula addresses multiple factors that contribute to GI health. Supports the integrity of the gastric lining by promoting the growth of gastric mucosal cells.

Key nutrients help to support GI immune function.

This product is non-GMO and gluten-free.

Certified Gluten Free GFCO.org (Gluten-Free Certification Organization)

Multi-dimensional GI support & protection

Formula

Lecithin and astaxanthin have demonstrated protective effects on the gastric environment. Green tea and arabinoglactans may-help promote the growth of healthy intestinal microflora. Arabinogalactans may help promote the production of beneficial short-chain fatty acids, an important fuel for intestinal cells. Plantain has been shown in a lab setting to support the integrity of the gastric lining. Targeted antioxidants help protect the gastric mucosa.

Suggested/Recommended/Usage/Directions

Directions: Mix about one level tablespoon (7.5 g) in two to four ounces of juice or water once daily, or as directed by your healthcare practitioner.

Precautions

Caution: If pregnant or nursing, or taking medication, consult your healthcare practitioner before use.

Keep out of the reach of children.

Practitioner Exclusive

Storage

Storage: Keep tightly closed in a cool, dry place.

Seals/Symbols

Certified Gluten Free GFCO.org (Gluten-Free Certification Organization)

FDA Statement of Identity

Dietary Supplement

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.

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

See for yourself

Endefen by Metagenics label

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

Endefen 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 Endefen by Metagenics

These are the 12 active ingredients this product is made of. Select any to open its full monograph.

Serving size7.5 Gram(s) Dosage formPowder Servings per container56 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.

Sodium

Interacts with
205 drugs
5 mg per serving

Sodium is an essential mineral and electrolyte your body needs to balance fluids, support nerves, and help muscles work. Most people in modern diets g...

Sodium monograph & interactions

Vitamin C

Interacts with
207 drugs
150 mg per serving Form: Calcium Ascorbate

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

Dietary Fiber

Interacts with
2,025 drugs
2 Gram(s) per serving

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. I...

Dietary Fiber monograph & interactions

Protein

1 Gram(s) per serving

Soy Lecithin

No known
interactions
500 mg per serving

Lecithin is a natural fatty substance found in foods and made by the body that is widely used as a supplement and food emulsifier. Evidence supporting...

Soy Lecithin monograph & interactions
  • › Phosphatides

D-Mannose

No known
interactions
125 mg per serving

D-mannose is a natural sugar most often used to help prevent urinary tract infections, especially those caused by E. coli. Early research is promising...

D-Mannose monograph & interactions

Astaxanthin

Interacts with
671 drugs
250 mcg per serving

Astaxanthin is a reddish carotenoid pigment with strong antioxidant activity in the lab, and it is widely promoted for skin, eye, heart, and exercise...

Astaxanthin monograph & interactions

Apple, Powder

Interacts with
300 drugs
1 Gram(s) per serving

Apples are a nutritious whole food that provides fiber, vitamins, and antioxidant plant compounds, and eating them regularly fits well into a healthy...

Apple, Powder monograph & interactions

Arabinogalactans

Interacts with
121 drugs
750 mg per serving Form: Larch Gum

Larch arabinogalactan is a soluble fiber from larch trees that is mainly used as a prebiotic and for immune support. Early research is interesting but...

Arabinogalactans monograph & interactions

Chinese Cinnamon, Powder

Interacts with
442 drugs
350 mg per serving Form: Cinnamomum cassia, Powder

Cassia cinnamon is the common, inexpensive cinnamon used in cooking, and it is also taken as a supplement, most often for blood sugar support. The evi...

Chinese Cinnamon, Powder monograph & interactions

Plantain, Powder

1 Gram(s) per serving

Green Tea Leaf Extract, Decaffeinated

Interacts with
1,293 drugs
125 mg per serving Form: Caffeine

Green tea is a popular beverage rich in antioxidants called catechins, and drinking it in normal amounts is considered safe for most people. Concentra...

Green Tea Leaf Extract, Decaffeinated monograph & interactions
  • › Epigallocatechin Gallate
  • › Catechins

Other (inactive) ingredients: Rice Bran, Xylitol, Rice Syrup, Solids, Natural Flavors. These complete the product’s ingredient list but are not active constituents.

Interaction report

Endefen by Metagenics Drug Interactions

Want to check YOUR meds against Endefen?

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
2,270Drugs
57 Major 1,402 Moderate 811 Minor

Ingredients driving the most interactions

Dietary Fiber 2,025
Green Tea Leaf Extract, Decaffeinated 1,293
Astaxanthin 671
Chinese Cinnamon, Powder 442
Apple, Powder 300

Individual Drug Interactions

The ingredients in Endefen interact with 2,270 drugs. Click any drug to see the details.

8 of the 12 ingredients in Endefen interact with drugs. Each result below shows which ingredient is responsible. Dietary Fiber Green Tea Leaf Extract, Decaffeinated Astaxanthin Chinese Cinnamon, Powder Apple, Powder Vitamin C Sodium Arabinogalactans

Each ingredient & the kinds of drugs it affects

For each ingredient in Endefen 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.

Dietary Fiber7 drug types · 2,025 drugs

Carbamazepine (Tegretol)

Theoretically, black psyllium might reduce the effects of carbamazepine and increase the risk for convulsions.
Theoretically, black psyllium might reduce carbamazepine absorption. A preliminary study using blond psyllium reported decreased carbamazepine bioavailability due to binding of the drug to psyllium, as well as reduction of available fluid in the gut for dissolution of the drug. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Lithium

Theoretically, taking black psyllium at the same time as lithium might reduce lithium absorption.
The fiber in black psyllium might reduce lithium absorption and plasma levels. Some case reports describe a reduction in plasma lithium levels with concomitant administration of blond psyllium. This was reversed when psyllium was stopped. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Metformin (Glucophage)

Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Animal research shows that concurrent consumption of blond psyllium with metformin slows and increases the absorption of metformin. This interaction may also occur with black psyllium. To avoid changes in absorption, take psyllium 30-60 minutes after metformin.

Likelihood Possible Evidence D
Olanzapine (Zyprexa)

Theoretically, taking black psyllium at the same time as olanzapine might reduce olanzapine absorption.
The fiber in black psyllium might decrease the absorption of olanzapine. A single case report describes a reduction in the effectiveness of olanzapine when it was concomitantly administered with an unspecified type of psyllium 3 grams orally twice daily. This effect was reversed when psyllium was stopped.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, taking black psyllium at the same time as digoxin might reduce digoxin absorption and decrease digoxin levels.
Psyllium might bind digoxin in the gut. However, some clinical evidence suggests that psyllium does not impact digoxin absorption.

Likelihood Unlikely Evidence B
Ethinyl Estradiol

Theoretically, taking black psyllium at the same time as ethinyl estradiol might alter levels of estradiol.
Concurrent use of blond psyllium with ethinyl estradiol results in a slight increase in the extent of ethinyl estradiol absorption and a slower rate of absorption. This is unlikely to be clinically significant.

Likelihood Unlikely Evidence D
Oral Drugs

Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Psyllium seems to have variable effects on drug absorption. To avoid changes in absorption, take psyllium 30-60 minutes after oral medications. Animal research shows that blond psyllium delays and increases the absorption of metformin and ethinyl estradiol. Case reports and animal research suggest that blond psyllium might reduce absorption of lithium, digoxin, olanzapine, and carbamazepine. Finally, some pharmacokinetic studies show that psyllium does not affect the absorption of levothyroxine or warfarin. Although many of these studies evaluated blond psyllium, the fiber content in black psyllium may have similar effects.

Likelihood Possible Evidence B
Dietary Fiber full monograph & interactions

Green Tea Leaf Extract, Decaffeinated58 drug types · 1,293 drugs

Atorvastatin (Lipitor)

Green tea extract seems to reduce the levels and clinical effects of atorvastatin.
In healthy humans, taking green tea extract 300 mg or 600 mg along with atorvastatin reduces plasma levels of atorvastatin by approximately 24%. The elimination of atorvastatin is not affected. Atorvastatin is a substrate of organic anion-transporting polypeptides (OATPs). Research shows that two of the major catechins found in green tea, epicatechin gallate (ECG) and epigallocatechin gallate (EGCG), inhibit OATPs. Some OATPs are expressed in the small intestine and are responsible for the uptake of drugs and other compounds, which may have resulted in reduced plasma levels of atorvastatin. It is not clear if drinking green tea alters the absorption of atorvastatin.

Likelihood Likely Evidence B
Ephedrine

Theoretically, concomitant use might increase the risk for stimulant adverse effects.
Green tea contains caffeine. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death.

Likelihood Probable Evidence D
Nadolol (Corgard)

Green tea seems to reduce the levels and clinical effects of nadolol.
Preliminary clinical research shows that green tea consumption reduces plasma concentrations of nadolol. Compared to a control group, both peak levels and total drug exposure (AUC) of nadolol were reduced by approximately 85% in subjects who drank green tea daily for two weeks. Drinking green tea with nadolol also significantly reduced nadolol's systolic blood pressure lowering effect. Other clinical research shows that a single dose of green tea can affect plasma nadolol levels for at least one hour. Green tea catechins have been shown to inhibit organic anion transporting polypeptides (OATP), one of which, OATP1A2, is involved in the uptake of nadolol in the intestine The interaction is thought to be due primarily to the epigallocatechin gallate (EGCG) content of green tea.

Likelihood Likely Evidence B
5-Fluorouracil

Theoretically, high doses of green tea might increase the effects and side effects of 5-fluorouracil.
Animal research shows that taking green tea in amounts equivalent to about 6 cups daily in humans for 4 weeks prior to receiving a single injection of 5-fluorouracil increases the maximum plasma levels of 5-fluorouracil by about 2.5-fold and the area under the curve by 425%.

Likelihood Possible Evidence D
Adenosine (Adenocard)

Theoretically, green tea might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Green tea contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine doesn't seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Possible Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, green tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Conflicting reports exist regarding the effect of green tea on bleeding risk when used with anticoagulant or antiplatelet drugs; however, most evidence suggests that drinking green tea in moderate amounts is unlikely to cause a significant interaction. Green tea contains small amounts of vitamin K, approximately 7 mcg per cup. Some case reports have associated the antagonism of warfarin with the vitamin K content of green tea. However, these reports are rare, and very large doses of green tea (about 8-16 cups daily) appear to be needed to cause these effects. Furthermore, the catechins and caffeine in green tea are reported to have antiplatelet activity.

Likelihood Unlikely Evidence D
Beta-Adrenergic Agonists

Green tea contains caffeine. Theoretically, concomitant use of large amounts of caffeine might increase cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Bortezomib (Velcade)

Theoretically, green tea might interfere with the effects of bortezomib.
In vitro research shows that green tea polyphenols, such as epigallocatechin gallate (EGCG), interact with bortezomib and block its proteasome inhibitory action. This prevents the induction of cell death in multiple myeloma or glioblastoma cancer cell lines. Advise patients taking bortezomib, not to take green tea.

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

Theoretically, green tea might reduce the effects of carbamazepine and increase the risk for convulsions.
Green tea contains caffeine. Animal research suggests that taking caffeine can lower the anticonvulsant effects of carbamazepine and can induce seizures when taken in doses above 400 mg/kg. Human research has shown that taking caffeine 300 mg in three divided doses along with carbamazepine 200 mg reduces the bioavailability of carbamazepine by 32% and prolongs the plasma half-life of carbamazepine 2-fold in healthy individuals.

Likelihood Possible Evidence D
Celiprolol (Celicard)

Theoretically, green tea might reduce the levels and clinical effects of celiprolol.
In a small human study, taking green tea daily for 4 days appears to decrease blood and urine levels of celiprolol by at least 98%. This interaction is possibly due to the inhibition of organic anion transporting polypeptide (OATP). Green tea catechins have been shown to inhibit organic anion transporting polypeptides (OATP), one of which, OATP1A2, is found in the intestine The interaction is thought to be due primarily to the epigallocatechin gallate (EGCG) content of green tea.

Likelihood Possible Evidence D
Cimetidine (Tagamet)

Theoretically, concomitant use might increase the effects and adverse effects of caffeine in green tea.
Green tea contains caffeine. Cimetidine can reduce caffeine clearance by 31% to 42%.

Likelihood Likely Evidence B
Clozapine (Clozaril)

Theoretically, green tea might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Animal research suggests that, although green tea extract does not affect the elimination of clozapine, it delays the time to reach peak concentration and reduces the peak plasma levels. Also, concomitant administration of green tea and clozapine might theoretically cause acute exacerbation of psychotic symptoms due to the caffeine in green tea. Caffeine can increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg daily inhibit clozapine metabolism. Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Researchers speculate that caffeine might inhibit CYP1A2. However, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients be more sensitive to the interaction between clozapine and caffeine.

Likelihood Possible Evidence B
Contraceptive Drugs

Theoretically, concomitant use might increase the effects and adverse effects of caffeine found in green tea.
Green tea contains caffeine. Oral contraceptives can decrease caffeine clearance by 40% to 65%.

Likelihood Probable Evidence B
Cytochrome P450 1A2 (Cyp1A2) Inhibitors

Theoretically, concomitant use might increase the levels and adverse effects of caffeine.
Green tea contains caffeine. Caffeine is metabolized by cytochrome P450 1A2 (CYP1A2),. Theoretically, drugs that inhibit CYP1A2 may decrease the clearance rate of caffeine from green tea and increase caffeine levels.

Likelihood Possible Evidence D
Dipyridamole (Persantine)

Theoretically, green tea might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Green tea contains caffeine. Caffeine might inhibit dipyridamole-induced vasodilation. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. Methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram might increase the risk of adverse effects from caffeine.
In human research, disulfiram decreases the clearance and increases the half-life of caffeine.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, using green tea with diuretic drugs might increase the risk of hypokalemia.
Green tea contains caffeine. In excessive amounts, caffeine can reduce potassium levels due to stimulation of the sodium-potassium pump. Diuretics can also cause lower potassium levels.

Likelihood Possible Evidence D
Estrogens

Theoretically, estrogens might increase the levels and adverse effects of caffeine.
Green tea contains caffeine. Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Ethosuximide (Zarontin)

Theoretically, green tea might reduce the effects of ethosuximide and increase the risk for convulsions.
Green tea contains caffeine. Animal research suggests that caffeine 92.4 mg/kg can decrease the anticonvulsant activity of ethosuximide. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Felbamate (Felbatol)

Theoretically, green tea might reduce the effects of felbamate and increase the risk for convulsions.
Green tea contains caffeine. Animal research suggests that a high dose of caffeine 161.7 mg/kg can decreases the anticonvulsant activity of felbamate. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Fexofenadine (Allegra)

Green tea can decrease blood levels of fexofenadine.
Clinical research shows that green tea can significantly decrease blood levels and excretion of fexofenadine. Taking green tea extract with a dose of fexofenadine decreased bioavailability of fexofenadine by about 30%. In vitro, green tea inhibits the cellular accumulation of fexofenadine by inhibiting the organic anion transporting polypeptide (OATP) drug transporter. Research shows that two of the major catechins found in green tea, epicatechin gallate (ECG) and epigallocatechin gallate (EGCG), inhibit OATPs, specifically OATP1A2, OATP1B1, and OATP2B1. In addition, green tea has been shown to reduce the absorption of some drugs that are OATP substrates.

Likelihood Probable Evidence B
Flutamide (Eulexin)

Theoretically, green tea might increase the levels and adverse effects of flutamide.
Green tea contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide. Theoretically, concomitant use of caffeine and flutamide might increase serum concentrations of flutamide and increase the risk adverse effects.

Likelihood Possible Evidence D
Fluvoxamine (Luvox)

Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
Green tea contains caffeine. Fluvoxamine reduces caffeine metabolism.

Likelihood Probable Evidence D
Hepatotoxic Drugs

Theoretically, concomitant use might have additive adverse hepatotoxic effects.
Green tea extract supplements have been linked to several cases of hepatotoxicity and might have additive hepatotoxic effects with other drugs..

Likelihood Unlikely Evidence D
Imatinib (Gleevec)

Theoretically, green tea might reduce the levels and clinical effects of imatinib.
In animal research, a single dose of green tea extract reduces the area under the curve (AUC) of imatinib by up to approximately 64% and its main metabolite N-desmethyl imatinib by up to approximately 81%. This interaction has not been shown in humans. The mechanism of action is unclear but may involve multiple pathways.

Likelihood Possible Evidence D
Green Tea Leaf Extract, Decaffeinated full monograph & all 58 interactions

Astaxanthin2 drug types · 671 drugs

Cytochrome P450 2B6 (Cyp2B6) Substrates

Theoretically, astaxanthin may decrease levels of drugs metabolized by CYP2B6.
In vitro research shows that astaxanthin induces cytochrome CYP2B6 enzyme activity in human hepatocytes. This effect has not been reported in humans.

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

Theoretically, astaxanthin may decrease levels of drugs metabolized by CYP3A4.
In vitro research shows that astaxanthin induces CYP3A4 enzyme activity in human hepatocytes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Astaxanthin full monograph & interactions

Chinese Cinnamon, Powder2 drug types · 442 drugs

Antidiabetes Drugs

Theoretically, cassia cinnamon may have additive effects with antidiabetes drugs.
Cassia cinnamon may lower blood glucose levels, and have additive effects in patients treated with antidiabetic agents. Dose adjustments to diabetes medications might be necessary.

Likelihood Possible Evidence B
Hepatotoxic Drugs

Theoretically, large doses of cassia cinnamon might cause additive effects when used with hepatotoxic drugs.
There is some concern that ingesting large amounts of cassia cinnamon for an extended duration might cause hepatotoxicity in some people. Cassia cinnamon contains coumarin, which can cause hepatotoxicity in animal models. In humans, very high doses of coumarin from 50-7000 mg/day can result in hepatotoxicity that resolves when coumarin use is discontinued. Lower amounts might also cause liver problems in sensitive people, such as those with liver disease or those taking potentially hepatotoxic agents.

Likelihood Possible Evidence D
Chinese Cinnamon, Powder full monograph & interactions

Apple, Powder7 drug types · 300 drugs

Organic Anion-Transporting Polypeptide Substrates (Oatp)

Concomitant consumption of apple juice can significantly decrease oral absorption and blood levels of OATP substrates.
Research shows that consuming apple juice inhibits OATP, which reduces bioavailability of oral drugs that are substrates of OATP. Fexofenadine, atenolol, and aliskiren are substrates of OATP. Clinical research shows that coadministration of apple juice decreases bioavailability of fexofenadine by up to 78%, aliskiren by 63%, and atenolol by up to 82%. These effects appear to increase with larger quantities of apple juice. It is thought that apple juice might affect OATP for only a short time. Therefore, separating drug administration and consumption of apple juice by at least 4 hours might avoid this interaction.

Likelihood Likely Evidence B
Aliskiren (Tekturna, Rasilez)

Concomitant consumption of apple juice can significantly decrease oral absorption and blood levels of aliskiren.
Pharmacokinetic research shows that coadministration of apple juice 200 mL along with aliskiren 150 mg decreases the bioavailability of aliskiren by 63%. Apple juice seems to inhibit organic anion transporting polypeptide (OATP), which is involved in drug uptake in the gut, liver, and kidney. It is thought that apple juice might affect OATP for only a short time. Therefore, separating drug administration and consumption of apple juice by at least 4 hours might avoid this interaction.

Likelihood Probable Evidence B
Antidiabetes Drugs

Theoretically, consuming apple juice with antidiabetes drugs might interfere with blood glucose control.
Clinical research suggests that consuming apples or drinking apple juice can raise blood glucose levels, with the effects of drinking apple juice being more significant than consuming apples.

Likelihood Possible Evidence D
Antihypertensive Drugs

Consuming apple juice with antihypertensive drugs might interfere with blood pressure control.
Some clinical evidence suggests that consuming apple and cherry juice can increase blood pressure in elderly patients.

Likelihood Probable Evidence B
Atenolol (Tenormin)

Concomitant consumption of apple juice can significantly decrease oral absorption and blood levels of atenolol.
Pharmacokinetic research shows that coadministration of apple juice 600-1200 mL decreases levels of atenolol by 58% to 82% in a dose-dependent manner. Apple juice seems to inhibit organic anion transporting polypeptide (OATP), which is involved in drug uptake in the gut, liver, and kidney. It is thought that apple juice might affect OATP for only a short time. Therefore, separating drug administration and consumption of apple juice by at least 4 hours might avoid this interaction.

Likelihood Probable Evidence B
Fexofenadine (Allegra)

Concomitant consumption of apple juice can significantly decrease oral absorption and blood levels of fexofenadine.
Pharmacokinetic research shows that coadministration of apple juice 400-1200 mL along with fexofenadine 60-120 mg decreases bioavailability of fexofenadine by up to 78%. Coadministration with smaller quantities of apple juice (150 mL or less) does not appear to affect the bioavailability of fexofenadine. Apple juice seems to inhibit organic anion transporting polypeptide (OATP), which is involved in drug uptake in the gut, liver, and kidney. It is thought that apple juice might affect OATP for only a short time. Therefore, separating drug administration and consumption of apple juice by at least 4 hours might avoid this interaction.

Likelihood Likely Evidence B
Lithium

There is some concern that concomitant consumption of apple juice might decrease oral absorption and blood levels of lithium.
In one case report, a patient had an undetectable serum lithium level when lithium citrate was administered with apple juice. When lithium was administered with an alternative beverage, the lithium level became detectable and the patient demonstrated clinical improvement.

Likelihood Possible Evidence D
Apple, Powder full monograph & interactions

Vitamin C13 drug types · 207 drugs

Alkylating Agents

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

Likelihood Possible Evidence D
Aluminum

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

Likelihood Probable Evidence B
Antitumor Antibiotics

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

Likelihood Possible Evidence D
Estrogens

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

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

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

Likelihood Possible Evidence D
Indinavir (Crixivan)

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

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

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

Likelihood Probable Evidence B
Warfarin (Coumadin)

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

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

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

Likelihood Probable Evidence B
Aspirin

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

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

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

Likelihood Possible Evidence B
Niacin

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

Likelihood Possible Evidence A
Salsalate (Disalcid)

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

Likelihood Possible Evidence B
Vitamin C full monograph & interactions

Sodium7 drug types · 205 drugs

Antihypertensive Drugs

Theoretically, a high intake of dietary sodium might reduce the effectiveness of antihypertensive drugs.
High intake of dietary sodium can increase systolic and diastolic blood pressure. Also, high intake of sodium may necessitate increased use of antihypertensive medications to achieve blood pressure control in some patients, such as those with chronic kidney disease.

Likelihood Probable Evidence A
Corticosteroids

Concomitant use of mineralocorticoids and some glucocorticoids with sodium supplements might increase the risk of hypernatremia.
Mineralocorticoids and some glucocorticoids (corticosteroids) cause sodium retention. This effect is dose-related and depends on mineralocorticoid potency. It is most common with hydrocortisone, cortisone, and fludrocortisone, followed by prednisone and prednisolone.

Likelihood Possible Evidence D
Didanosine (Videx)

Concomitant use of didanosine with additional sodium from dietary or supplemental sources may increase the risk of hypernatremia.
Didanosine formulations contain a significant amount of sodium.

Likelihood Probable Evidence C
Lithium

Altering dietary intake of sodium might alter the levels and clinical effects of lithium.
High sodium intake can reduce plasma concentrations of lithium by increasing lithium excretion. Reducing sodium intake can significantly increase plasma concentrations of lithium and cause lithium toxicity in patients being treated with lithium carbonate. Stabilizing sodium intake is shown to reduce the percentage of patients with lithium level fluctuations above 0.8 mEq/L. Patients taking lithium should avoid significant alterations in their dietary intake of sodium.

Likelihood Probable Evidence B
Sodium Phosphates

Theoretically, concomitant use of sodium phosphate with sodium supplements might increase the risk of hypernatremia.
Use of high doses (> 45 mL in 24 hours) of sodium phosphate, such as those used for bowel cleansing before surgery, can lead to serious electrolyte disturbances, including hypernatremia. The risk of hypernatremia is highest in the elderly and people with other risk factors for electrolyte disturbances.

Likelihood Possible Evidence D
Sodium-Containing Drugs

Concomitant use of sodium-containing drugs with additional sodium from dietary or supplemental sources may increase the risk of hypernatremia and long-term sodium-related complications.
The Chronic Disease Risk Reduction (CDRR) intake level of 2.3 grams of sodium daily indicates the intake at which it is believed that chronic disease risk increases for the apparently healthy population. Some medications contain high quantities of sodium. When used in conjunction with sodium supplements or high-sodium diets, the CDRR may be exceeded. Additionally, concomitant use may increase the risk for hypernatremia; this risk is highest in the elderly and people with other risk factors for electrolyte disturbances.

Likelihood Possible Evidence D
Tolvaptan (Samsca)

Theoretically, concomitant use of tolvaptan with sodium might increase the risk of hypernatremia.
Tolvaptan is a vasopressin receptor 2 antagonist that is used to increase sodium levels in patients with hyponatremia. Patients taking tolvaptan should use caution with the use of sodium salts such as sodium chloride.

Likelihood Probable Evidence C
Sodium full monograph & interactions

Arabinogalactans1 drug type · 121 drugs

Immunosuppressants

Theoretically, larch arabinogalactan might interfere with immunosuppression therapy due to immunostimulant effects. Immunosuppressant drugs include azathioprine (Imuran), basiliximab (Simulect), cyclosporine (Neoral, Sandimmune), daclizumab (Zenapax), muromonab-CD3 (OKT3, Orthoclone OKT3), mycophenolate (CellCept), tacrolimus (FK506, Prograf), sirolimus (Rapamune), prednisone (Deltasone, Orasone), corticosteroids (glucocorticoids), and other drugs.

Likelihood Possible Evidence D
Arabinogalactans full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Endefen, from the product label.

Metagenics

See all Metagenics products
Name
Metagenics
City
Gig Harbor
State
WA
ZipCode
98332
Phone Number
800 692 9400
Web Address
metagenics.com
Pharmacist Counseling Corner

Endefen by Metagenics: Common Questions

Does Endefen by Metagenics interact with any medications?
Yes. Based on its ingredients, Endefen has a known interaction with 2,270 medications, including 57 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Endefen contains 12 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.
Will this help with urinary tract infections?
D-Mannose is in the formula, but our data rate it possibly ineffective for urinary tract infections—the very condition many people take it for. Talk to your doctor about whether this product is the right choice for your situation.
Is this safe during pregnancy?
The safety data for most ingredients are incomplete or mixed. Vitamin C is likely safe at typical amounts, and Chinese Cinnamon is rated likely safe, but Sodium, D-Mannose, astaxanthin, and Apple Powder lack enough information. Please discuss with your doctor or midwife before starting.
Can I take this if I'm on birth control?
The Vitamin C in this product can increase blood levels of estrogen from oral contraceptives by up to 55% in some cases. This is a Moderate-severity interaction—talk with your pharmacist or doctor before using Endefen.
What are the most common side effects?
D-Mannose may cause bloating, diarrhea, or nausea. Astaxanthin can cause loose stools or red-colored stool. Arabinogalactans and Apple Powder may cause bloating and flatulence as fibers. Vitamin C at high doses can trigger stomach cramps or diarrhea. Most people tolerate the formula without trouble, but those with a history of Rosaceae fruit allergies (apricot, almond, peach, pear, strawberry) should be cautious.
Is the sodium content safe?
This product contains sodium, which at high intake can raise blood pressure and stress your kidneys—especially if you're already taking blood pressure medication, corticosteroids, or lithium. Don't add this to your routine without talking to your pharmacist or doctor first about sodium safety for you.
Does this have fillers?
The formula contains inactive ingredients: rice bran, xylitol, rice syrup solids, and natural flavors. These are excipients that help with texture and taste.

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.

Endefen label
Go deeper

The Full Monographs Behind Endefen’s Ingredients

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

Herb & supplement monograph

Sodium

Interacts with 205 drugs

Sodium is an essential mineral and electrolyte your body needs to balance fluids, support nerves, and help muscles work. Most people in modern diets get more than enough—often too much—from...

Read the full Sodium monograph → Herb & supplement monograph

Vitamin C

Interacts with 207 drugs

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

Read the full Vitamin C monograph → Herb & supplement monograph

Black Psyllium

Interacts with 2,025 drugs

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. It is best known and most studied for rel...

Read the full Black Psyllium monograph → Herb & supplement monograph

Lecithin

Lecithin is a natural fatty substance found in foods and made by the body that is widely used as a supplement and food emulsifier. Evidence supporting most of its health claims is limited, t...

Read the full Lecithin monograph → Herb & supplement monograph

D-mannose

D-mannose is a natural sugar most often used to help prevent urinary tract infections, especially those caused by E. coli. Early research is promising for prevention, but the evidence is sti...

Read the full D-mannose monograph → Herb & supplement monograph

Astaxanthin

Interacts with 671 drugs

Astaxanthin is a reddish carotenoid pigment with strong antioxidant activity in the lab, and it is widely promoted for skin, eye, heart, and exercise benefits. Early human studies are promis...

Read the full Astaxanthin monograph → Herb & supplement monograph

Apple

Interacts with 300 drugs

Apples are a nutritious whole food that provides fiber, vitamins, and antioxidant plant compounds, and eating them regularly fits well into a healthy diet. While research suggests apples may...

Read the full Apple monograph → Herb & supplement monograph

Larch Arabinogalactan

Interacts with 121 drugs

Larch arabinogalactan is a soluble fiber from larch trees that is mainly used as a prebiotic and for immune support. Early research is interesting but limited, and most claims are not yet fi...

Read the full Larch Arabinogalactan monograph → Herb & supplement monograph

Cassia Cinnamon

Interacts with 442 drugs

Cassia cinnamon is the common, inexpensive cinnamon used in cooking, and it is also taken as a supplement, most often for blood sugar support. The evidence for its health benefits is mixed a...

Read the full Cassia Cinnamon monograph → Herb & supplement monograph

Green Tea

Interacts with 1,293 drugs

Green tea is a popular beverage rich in antioxidants called catechins, and drinking it in normal amounts is considered safe for most people. Concentrated green tea extracts are a different s...

Read the full Green Tea monograph →
Sources

Sources & How We Checked

Endefen'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 388 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.

Sodium 38 references
  1. Garabedian-Ruffalo SM, Ruffalo RL. Drug and nutrient interactions. Am Fam Physician 1986;33:165-74.
  2. Food and Drug Administration Science Background: Safety of Sodium Phosphates Oral Solution. September 17, 2001. Available at: http://www.fda.gov/cder/drug/safety/sodiumphospate.htm
  3. Coton T, Mallaret C, Coilliot C, Carre D, Guisset M. Severe acute ulcerated gastritis induced by salt. Presse Med 2009;38(3):499-500. PubMed
  4. Frings-Meuthen P, Buehlmeier J, Baecker N, et al. High sodium chloride intake exacerbates immobilization-induced bone resorption and protein losses. J Appl Physiol 2011;111(2):537-542. PubMed
  5. Frings-Meuthen P, Baecker N, Heer M. Low-grade metabolic acidosis may be the cause of sodium chloride-induced exaggerated bone resorption. J Bone Miner Res 2008;23(4):517-524. PubMed
  6. Alam S, Johnson AG. A meta-analysis of randomised controlled trials (RCT) among healthy normotensive and essential hypertensive elderly patients to determine the effect of high salt (NaCl) diet of blood pressure. J Hum Hypertens 1999;13(6):367-74.
  7. Boudville N, Ward S, Benaroia M, House AA. Increased sodium intake correlates with greater use of antihypertensive agents by subjects with chronic kidney disease. Am J Hypertens 2005;18(10):1300-5. PubMed
  8. Bennett WM. Drug interactions and consequences of sodium restriction. Am J Clin Nutr 1997;65(2 Suppl):678S-681S. PubMed
  9. Okusa MD, Crystal LJ. Clinical manifestations and management of acute lithium intoxication. Am J Med 1994;97(4):383-9. PubMed
  10. Food and Nutrition Board, Institute of Medicine. Dietary reference intakes for water, potassium, sodium, chloride, and sulfate. Washington, DC: National Academy Press, 2005. Available at: http://www.nap.edu/openbook.php?record_id=10925. DOI
  11. D'Elia L, Rossi G, Ippolito R, Cappuccio FP, Strazzullo P. Habitual salt intake and risk of gastric cancer: a meta-analysis of prospective studies. Clin Nutr 2012;31(4):489-98. PubMed
  12. Goldsmith SR. Hyponatremia in heart failure: time for a trial. J Card Fail 2013;19(6):398-400. PubMed
  13. Willocks L, Brettle R, Keen J, Valentine C, Pinching AJ. Formulations of didanosine (ddI) and salt overload. Lancet 1992;339(8786):190.
  14. Chen L, Zhang Z, Chen W, Whelton PK, Appel LJ. Lower Sodium Intake and Risk of Headaches: Results From the Trial of Nonpharmacologic Interventions in the Elderly. Am J Public Health. 2016;106(7):1270-5. PubMed
  15. Cook NR, Appel LJ, Whelton PK. Lower levels of sodium intake and reduced cardiovascular risk. Circulation. 2014;129(9):981-9. PubMed
  16. Cook NR, Appel LJ, Whelton PK. Sodium Intake and All-Cause Mortality Over 20 Years in the Trials of Hypertension Prevention. J Am Coll Cardiol. 2016;68(15):1609-1617. PubMed
  17. Mente A, O'Donnell M, Rangarajan S, et al. Associations of urinary sodium excretion with cardiovascular events in individuals with and without hypertension: a pooled analysis of data from four studies. Lancet. 2016;388(10043):465-75. PubMed
  18. Moosavian SP, Haghighatdoost F, Surkan PJ, Azadbakht L. Salt and obesity: a systematic review and meta-analysis of observational studies. Int J Food Sci Nutr. 2017;68(3):265-277. PubMed
  19. O'Donnell M, Mente A, Rangarajan S, et al. Urinary sodium and potassium excretion, mortality, and cardiovascular events. N Engl J Med. 2014;371(7):612-23. DOI
  20. Poggio R, Gutierrez L, Matta MG, Elorriaga N, Irazola V, Rubinstein A. Daily sodium consumption and CVD mortality in the general population: systematic review and meta-analysis of prospective studies. Public Health Nutr. 2015;18(4):695-704. PubMed
  21. Stallings VA, Harrison M, Oria M; Committee to Review the Dietary Reference Intakes for Sodium and Potassium, Food and Nutrition Board, Health and Medicine Division, National Academies of Sciences, Engineering, and Medicine. Washington (DC): National Acad
  22. Mahtani KR, Heneghan C, Onakpoya I, et al. Reduced Salt Intake for Heart Failure: A Systematic Review. JAMA Intern Med. 2018 Dec 1;178(12):1693-1700. PubMed
  23. Yancy CW. Sodium Restriction in Heart Failure: Too Much Uncertainty-Do the Trials. JAMA Intern Med. 2018 Dec 1;178(12):1700-1701. PubMed
  24. He FJ, Campbell NRC, Ma Y, MacGregor GA, Cogswell ME, Cook NR. Errors in estimating usual sodium intake by the Kawasaki formula alter its relationship with mortality: implications for public health. Int J Epidemiol. 2018;47(6):1784-1795. PubMed
  25. Murthy K, Ondrey GJ, Malkani N, et al. THE EFFECTS OF HYPONATREMIA ON BONE DENSITY AND FRACTURES: A SYSTEMATIC REVIEW AND META-ANALYSIS. Endocr Pract. 2019;25(4):366-378. PubMed
  26. Messerli FH, Hofstetter L, Syrogiannouli L, et al. Sodium intake, life expectancy, and all-cause mortality. Eur Heart J 2021;42(21):2103-2112. PubMed
  27. Graudal NA, Hubeck-Graudal T, Jurgens G. Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride. Cochrane Database Syst Rev 2020;12(12):CD004022. PubMed
  28. Giatti S, Santos RB, Aielo AN, et al. Association of sodium with obstructive sleep apnea. The ELSA-Brasil study. Ann Am Thorac Soc 2021;18(3):502-510. PubMed
  29. Nan X, Lu H, Wu J, et al. The interactive association between sodium intake, alcohol consumption and hypertension among elderly in northern China: a cross-sectional study. BMC Geriatr 2021;21(1):135. PubMed
  30. Kyozuka H, Fukusda T, Murata T, et al. Impact of preconception sodium intake on hypertensive disorders of pregnancy: The Japan Environment and Children's study. Pregnancy Hypertens 2021;23:66-72. PubMed
  31. Zhao L, Ogden CL, Yang Q, et al. Association of usual sodium intake with obesity among US children and adolescents, NHANES 2009-2016. Obesity (Silver Spring) 2021;29(3):587-594. PubMed
  32. Ma Y, He FJ, Sun Q, et al. 24-Hour urinary sodium and potassium excretion and cardiovascular risk. N Engl J Med 2022;386(3):252-263. PubMed
  33. Liu J, Yang X, Zhang P, et al. Association of urinary sodium excretion and left ventricular hypertrophy in people with type 2 diabetes mellitus: A cross-sectional study. Front Endocrinol (Lausanne) 2021;12:728493. PubMed
  34. Filippini T, Malavolti M, Whelton PK, Vinceti M. Sodium intake and risk of hypertension: A systematic review and dose-response meta-analysis of observational cohort studies. Curr Hypertens Rep 2022;24(5):133-144. PubMed
  35. Wang DD, Li Y, Nguyen XT, et al. Dietary sodium and potassium intake and risk of non-fatal cardiovascular diseases: The million veteran program. Nutrients 2022;14(5):1121. PubMed
  36. Kwak JH, Park CH, Eun CS, et al. The associations of dietary intake of high sodium and low zinc with gastric cancer mortality: A prospective cohort study in Korea. Nutr Cancer 2022;74(10):3501-3508. PubMed
  37. George S, Maiti R, Mishra BR, Jena M, Mohapatra D. Effect of regulated add-on sodium chloride intake on stabilization of serum lithium concentration in bipolar disorder: A randomized controlled trial. Bipolar Disord 2023;25(1):66-75. PubMed
  38. Zhou TL, Schütten MTJ, Kroon AA, et al. Urinary Sodium Excretion and Salt Intake Are Not Associated With Blood Pressure Variability in a White General Population. J Am Heart Assoc 2023;12(1):e026578. PubMed

See these in context on the Sodium monograph →

Vitamin C 51 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
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Black Psyllium 18 references
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Lecithin 9 references
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D-mannose 6 references
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Apple 16 references
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Larch Arabinogalactan 8 references
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Cassia Cinnamon 20 references
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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