Major interaction on record — check this product against your medications before combining. Check your meds →
Dietary supplement

Citrigen Ingredients & Drug Interactions

by Genestra Brands

Citrigen label
See full label image
Capsule Category: Botanical
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 Citrigen 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

Citrigen is a dietary supplement by Genestra Brands with 4 active ingredients. Its ingredients are commonly taken for antioxidant support, weight loss, heart health.Based on those ingredients, 1,476 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Green Tea, Grapefruit (Citrus paradisi) fruit extract, Echinacea. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Citrigen by Genestra Brands

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

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HelloPharmacist Scorecard of Citrigen by Genestra Brands

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

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 4 of its 4 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Citrigen contains four active ingredients. Green tea is included for its polyphenol content and has been studied for viral and cancer-related uses.

Peppermint supports digestive and gastrointestinal comfort. Echinacea is traditionally used for immune support, though evidence for specific conditions is limited.

Grapefruit (Citrus paradisi) fruit extract rounds out the formula. The product also contains inactive ingredients—hypromellose, cellulose, magnesium silicate, and magnesium stearate—which serve as binders and capsule material.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Irritable bowel syndrome (IBS) — rated "Likely Effective" (Peppermint) (Natural Medicines).
  • On file: Human papillomavirus (HPV) — rated "Likely Effective" (Green Tea) (Natural Medicines).
  • On file: Barium enema-related colonic spasm — rated "Possibly Effective" (Peppermint) (Natural Medicines).
  • On file: Cardiovascular disease (CVD) — rated "Possibly Effective" (Green Tea) (Natural Medicines).
  • On file: Chemotherapy-induced nausea and vomiting (CINV) — rated "Possibly Effective" (Peppermint) (Natural Medicines).

Green tea in this product is likely effective for human papillomavirus (HPV) infection and possibly effective for ovarian cancer and high cholesterol (hyperlipidemia). Peppermint is likely effective for irritable bowel syndrome (IBS) and possibly effective for indigestion (dyspepsia), nausea from chemotherapy, and colonic spasm during medical procedures.

Echinacea has insufficient evidence in our data to rate its effectiveness for anxiety, athletic performance, ADHD, burns, chronic fatigue syndrome, migraine, or any other condition. Grapefruit extract similarly lacks established evidence for the conditions in our data, including acne, asthma, atherosclerosis, headache, respiratory infection, or depression.

The evidence, ingredient by ingredient Green Tea Peppermint Echinacea Grapefruit

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 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Green tea is generally well tolerated in moderate amounts as a beverage or supplement, though concentrated extracts at high doses have been rarely linked to liver injury. The most common side effects are gastrointestinal—bloating, constipation, diarrhea, nausea, and indigestion—especially with higher doses.

Serious effects are rare but include hepatotoxicity and a blood clotting condition (thrombotic thrombocytopenic purpura). Anaphylaxis has occurred in at least one case related to green tea proteins.

Peppermint is generally well tolerated; common side effects include abdominal pain, anal burning, belching, diarrhea, dry mouth, heartburn, nausea, and vomiting. One case of anaphylaxis to peppermint candy has been reported.

Echinacea is well tolerated short-term but may trigger allergic reactions, especially in those sensitive to ragweed and related plants; rare cases of hepatitis and anaphylaxis have been reported. Grapefruit and grapefruit juice are generally well tolerated, though large quantities may rarely cause arrhythmias or QT prolongation; preliminary research suggests frequent consumption may increase breast cancer risk in postmenopausal women.

Side effects, ingredient by ingredient Green Tea Peppermint Echinacea Grapefruit

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?
  • 4 of the 4 matched ingredients can interact with medications — Peppermint, Grapefruit, Green Tea, Echinacea.
  • 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; lithium.
  • For scale: 1,477 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 Citrigen, double-check the following medication types with your pharmacist: beta-blockers like nadolol (Corgard)—green tea can reduce their effectiveness by up to 85%; statins such as atorvastatin (Lipitor)—green tea lowers their levels; stimulants like ephedrine—dangerous when combined with green tea's caffeine; seizure medications including phenytoin (Dilantin), valproate, felbamate (Felbatol), and ethosuximide (Zarontin)—green tea may weaken their effects; heart and immune medications metabolized by liver enzymes (CYP2C19, CYP2C9, CYP3A4), including warfarin (Coumadin), amiodarone (Cordarone), and buspirone (BuSpar)—levels may rise; immunosuppressants like cyclosporine (Neoral, Sandimmune)—echinacea and peppermint may interfere; and chemotherapy drugs like etoposide (VePesid) and certain antihistamines. This is not an exhaustive list; use the checker below with your specific medications.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

Citrigen is designed for immune support and digestive comfort, but its strong interactions with heart medications, statins, seizure drugs, immunosuppressants, and many others make it essential to check your full medication list first. If you take any prescription medication—especially for heart rhythm, blood pressure, cholesterol, seizures, or immunity—talk to your pharmacist before starting this product.

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

Assessment coverage: 4 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 25, 2016.

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 Citrigen, straight from the product label.

Brand Genestra Brands
Barcode (UPC) 88319610031
Net contents 90 Vegetable Capsule(s)
Market status On market
Date entered into DSLD Jan 25, 2016
DSLD ID 56020
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Dairy 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 Citrigen by Genestra Brands, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
45
UPC/BARCODE
88319610031
IngredientAmount% DV
Green Tea40 mg--
Peppermint20 mg--
Echinacea500 mg--
Grapefruit (Citrus paradisi) fruit extract240 mg--

Other ingredients: Hypromellose, Cellulose, Magnesium Silicate, 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.
Suggested/Recommended/Usage/Directions

Recommended Adult Dose: Take two capsules daily with meals or as recommended by your healthcare practitioner.

Precautions

Risk Information: If you are pregnant or breastfeeding, consult your healthcare practitioner prior to use.

Quality Assurance: Safety-sealed for your protection and for product freshness. Do not use if outer seal is missing or broken.

Formulation

Guaranteed to contain no added wheat, starch, yeast, gluten, corn, soy, sodium, sugar, artificial coloring or flavoring, antimicrobial preservatives, dairy or animal products.

Ideal for vegans.

The capsules are made from 100% pure vegetable sources, free of preservatives and additives.

Storage

Store in a cool, dry place.

General

V2.0 528

FDA Statement of Identity

HERBAL SUPPLEMENT

Seals/Symbols

Seroyal

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

See for yourself

Citrigen by Genestra Brands label

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

Citrigen 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 Citrigen by Genestra Brands

These are the 4 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container45 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.

Green Tea

Interacts with
1,293 drugs
40 mg per serving

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 monograph & interactions

Peppermint

Interacts with
796 drugs
20 mg per serving

Peppermint is a popular herb with the best evidence supporting enteric-coated peppermint oil for easing IBS symptoms. It is generally well tolerated f...

Peppermint monograph & interactions

Echinacea

Interacts with
816 drugs
500 mg per serving

Echinacea is a popular herb taken to help prevent or shorten the common cold, but study results are mixed and the overall benefit appears small at bes...

Echinacea monograph & interactions

Grapefruit (Citrus paradisi) fruit extract

Interacts with
990 drugs
240 mg per serving Form: Bioflavonoids

Grapefruit is a nutritious citrus fruit rich in vitamin C and other nutrients, and it is generally safe to eat. However, grapefruit is famous for seri...

Grapefruit (Citrus paradisi) fruit extract monograph & interactions

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

Interaction report

Citrigen by Genestra Brands Drug Interactions

Want to check YOUR meds against Citrigen?

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
1,476Drugs
785 Major 618 Moderate 73 Minor

Ingredients driving the most interactions

Green Tea 1,293
Grapefruit (Citrus paradisi) fruit extract 990
Echinacea 816
Peppermint 796

Individual Drug Interactions

The ingredients in Citrigen interact with 1,476 drugs. Click any drug to see the details.

4 of the 4 ingredients in Citrigen interact with drugs. Each result below shows which ingredient is responsible. Green Tea Grapefruit (Citrus paradisi) fruit extract Echinacea Peppermint

Each ingredient & the kinds of drugs it affects

For each ingredient in Citrigen 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.

Green Tea58 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 full monograph & all 58 interactions

Grapefruit (Citrus paradisi) fruit extract62 drug types · 990 drugs

Amiodarone (Cordarone)

Grapefruit juice can increase blood levels of amiodarone, potentially increasing the effects and adverse effects of amiodarone.
Clinical research shows that grapefruit juice inhibits metabolism and increases absorption of amiodarone. Grapefruit juice increases amiodarone plasma levels by 50% and peak concentration by 84%.

Likelihood Probable Evidence B
Artemether (Artenam, Paluther)

Grapefruit juice can increase blood levels of oral artemether, potentially increasing the effects and adverse effects of artemether.
Clinical research shows that grapefruit juice increases the levels of oral artemether by 90% to 250% in healthy males.

Likelihood Likely Evidence B
Benzodiazepines

Grapefruit juice might increase blood levels of some oral benzodiazepines, potentially increasing the effects and adverse effects of these drugs.
Clinical research shows that grapefruit juice can increase plasma triazolam concentrations. Repeated consumption of grapefruit juice greatly increases triazolam concentrations and prolongs the half-life, probably due to inhibition of cytochrome P450 3A4 (CYP3A4). Some studies show that grapefruit juice, particularly when taken in large quantities, reduces the clearance and increases the maximum blood levels, area under the plasma concentration curve (AUC), and duration of effect of midazolam. However, there is no effect on intravenous midazolam. Grapefruit juice has also been shown to increase the maximum blood levels and duration of effect of diazepam, but the clinical significance of this is not known. This interaction does not appear to occur with alprazolam.

Likelihood Likely Evidence B
Buspirone (Buspar)

Grapefruit juice can increase blood levels of buspirone, potentially increasing the effects and adverse effects of buspirone.
Clinical research shows that grapefruit juice increases absorption and plasma concentrations of buspirone.

Likelihood Likely Evidence B
Calcium Channel Blockers

Grapefruit juice can increase blood levels of oral calcium channel blockers, potentially increasing the effects and adverse effects of these drugs.
Clinical research shows that grapefruit juice increases absorption and plasma concentrations of amlodipine, nifedipine, nisoldipine, verapamil, felodipine, nimodipine, nicardipine, diltiazem, pranidipine, nitrendipine, and manidipine, This interaction is likely the result of the inhibition of intestinal metabolism of these drugs by CYP3A4, although some research suggests grapefruit may alter plasma drug levels by reducing the rate of gastric emptying. Consuming grapefruit juice 1 liter daily increases steady state concentrations of verapamil by as much as 50%. However, some references dispute the clinical relevance of the interactions with amlodipine, diltiazem, and verapamil. Other research in healthy individuals suggests plasma levels of felodipine and nifedipine are not affected when given intravenously. There is considerable interindividual variability in the effect of grapefruit juice on drug metabolism, which might account for inconsistent study results. In healthy older adults, the hemodynamic response to felodipine plus grapefruit juice might be influenced by altered autonomic regulation. In older healthy adults, a single dose of grapefruit juice and felodipine enhanced the blood pressure-lowering effects of felodipine. However, after a week of grapefruit juice and felodipine (steady state), the hypotensive activity was reduced, possibly due to compensatory tachycardia. Research indicates it is necessary to withhold grapefruit juice for as long as 3 days to avoid interactions with felodipine and nisoldipine.

Likelihood Likely Evidence B
Carbamazepine (Tegretol)

Grapefruit juice can increase blood levels of carbamazepine, potentially increasing the effects and adverse effects of carbamazepine.
Clinical research shows that grapefruit juice increases absorption and plasma concentrations of carbamazepine.

Likelihood Likely Evidence B
Carvedilol (Coreg)

Grapefruit juice can increase blood levels of carvedilol, potentially increasing the effects and adverse effects of carvedilol.
Clinical research shows that grapefruit juice increases the bioavailability of a single dose of carvedilol by 16%.

Likelihood Likely Evidence B
Celiprolol (Celicard)

Grapefruit juice can decrease blood levels of celiprolol, potentially decreasing the clinical effects of celiprolol.
In human research, taking grapefruit juice within two hours of celiprolol appears to decrease absorption and blood levels of celiprolol by approximately 85%. This interaction is due to grapefruit-induced inhibition of organic anion transporting polypeptide (OATP). Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction.

Likelihood Probable Evidence B
Cisapride (Propulsid)

Grapefruit juice can increase blood levels of cisapride, potentially increasing the effects and adverse effects of cisapride.
Clinical research shows that grapefruit juice increases the absorption and plasma concentrations of cisapride. According to the cisapride prescribing information, grapefruit juice is contraindicated in patients taking cisapride.

Likelihood Likely Evidence B
Clomipramine (Anafranil)

Theoretically, grapefruit juice might increase blood levels of clomipramine, potentially increasing the effects and adverse effects of clomipramine.
Case reports have shown that clomipramine trough levels increase significantly after the addition of grapefruit juice to the therapeutic regimen.

Likelihood Probable Evidence D
Clopidogrel (Plavix)

Grapefruit juice can decrease blood levels of the active metabolite of clopidogrel, thereby decreasing the antiplatelet effect of clopidogrel.
Clopidogrel is an antiplatelet prodrug that is metabolized primarily by cytochrome P450 2C19 (CYP2C19) to form the active metabolite. A small clinical study shows that taking grapefruit juice with clopidogrel decreases plasma levels of the active metabolite by more than 80% and impairs the antiplatelet effect of clopidogrel. This effect is possibly due to grapefruit-induced inhibition of CYP2C19.

Likelihood Probable Evidence B
Cyclosporine (Neoral, Sandimmune)

Grapefruit juice can increase blood levels of oral cyclosporine, potentially increasing the effects and adverse effects of cyclosporine.
Clinical research shows that grapefruit juice increases the absorption and plasma concentrations of cyclosporine. The mechanism of action is unclear. However, there is no effect on intravenous cyclosporine.

Likelihood Likely Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Grapefruit juice can increase levels of drugs metabolized by CYP3A4.
Clinical research shows that grapefruit juice can inhibit CYP3A4 metabolism of drugs, causing increased drug levels and potentially increasing the risk of adverse effects. When taken orally, effects of grapefruit juice on CYP3A4 levels appear to last at least 48 hours. Grapefruit's ability to inhibit CYP3A4 has even been harnessed to intentionally increase levels of venetoclax, which is metabolized by CYP3A4, in an elderly patient with acute myeloid leukemia who could not afford full dose venetoclax. The lower dose of venetoclax in combination with grapefruit juice resulted in serum levels of venetoclax in the therapeutic reference range of full dose venetoclax and positive treatment outcomes for the patient.
Professional consensus recommends the consideration of patient age, existing medical conditions, additional medications, and the potential for additive adverse effects when evaluating the risks of concomitant use of grapefruit juice with any medication metabolized by CYP3A4. While all patients are at risk for interactions with grapefruit juice consumption, patients older than 70 years of age and those taking multiple medications are at the greatest risk for a serious or fatal interaction with grapefruit juice.

Likelihood Likely Evidence B
Dextromethorphan (Robitussin Dm, Others)

Grapefruit juice can increase blood levels of dextromethorphan, potentially increasing the effects and adverse effects of dextromethorphan.
Clinical research shows that grapefruit juice can inhibit cytochrome P450 3A4 (CYP3A4) metabolism, causing increased dextromethorphan levels.

Likelihood Probable Evidence B
Estrogens

Grapefruit juice can increase blood levels of estrogens, potentially increasing the effects and adverse effects of estrogens.
Clinical research shows that grapefruit increases the levels of endogenous and exogenous estrogens by inhibiting cytochrome P450 3A4 (CYP3A4) enzymes. Grapefruit juice increases exogenously administered 17-beta-estradiol by about 20% in females without ovaries and ethinyl-estradiol in healthy females.

Likelihood Probable Evidence B
Etoposide (Vepesid)

Grapefruit juice can decrease blood levels of etoposide, potentially decreasing the clinical effects of etoposide.
Clinical research shows that grapefruit juice decreases the absorption and plasma concentrations of etoposide. There is some evidence that grapefruit juice co-administered with oral etoposide can reduce levels of etoposide by about 26%. Grapefruit juice seems to inhibit organic anion transporting polypeptide (OATP), which is a drug transporter in the gut, liver, and kidney. Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction.

Likelihood Probable Evidence B
Halofantrine

Grapefruit juice can increase blood levels of halofantrine, potentially increasing the effects and adverse effects of halofantrine.
Clinical research shows that grapefruit juice inhibits cytochrome P450 3A4 (CYP3A4) metabolism, which increases halofantrine levels and peak concentration, as well as a marker of ventricular tachyarrhythmia potential.

Likelihood Probable Evidence B
Hmg-Coa Reductase Inhibitors ("Statins")

Grapefruit juice can increase blood levels of statins that are metabolized by cytochrome P450 3A4 (CYP3A4), potentially increasing the effects and adverse effects of these statins. Additionally, grapefruit juice might interfere with the bioavailability of statins that are substrates of organic anion transporting polypeptides (OATP).
Clinical research shows that grapefruit juice inhibits metabolism and increases absorption and plasma concentrations of statins that are metabolized by CYP3A4. These include lovastatin, simvastatin, and atorvastatin. Keep in mind that there is considerable variability in the effect of grapefruit juice on drug metabolism, so individual patient response is difficult to predict.
Some statins, including pravastatin, fluvastatin, pitavastatin, and rosuvastatin, are not metabolized by CYP3A4. However, grapefruit juice might still affect the bioavailability of these statins. These statins are substrates of OATP. Grapefruit juice can inhibit OATP. Therefore, grapefruit juice may reduce the bioavailability or increase drug levels of these statins depending on the type of OATP. However, grapefruit juice affects OATP for only a short time. Therefore, separating drug administration by at least 4 hours is likely to avoid this interaction.

Likelihood Likely Evidence B
Methadone (Dolophine)

Grapefruit juice can increase blood levels of methadone, potentially increasing the effects and adverse effects of methadone.
Clinical research shows that grapefruit juice inhibits the metabolism of methadone, increasing methadone levels and peak concentrations. In one case, a 51-year-old male taking methadone 90 mg daily and no other medications was found unresponsive. The patient reported drinking grapefruit juice 500 mL daily for 3 days prior to the event. Methadone is a substrate of cytochrome P450 3A4 (CYP3A4), and grapefruit juice-induced inhibition of CYP3A4 is the likely cause of this interaction.

Likelihood Probable Evidence B
Methylprednisolone

Grapefruit juice can increase blood levels of methylprednisolone, potentially increasing the effects and adverse effects of methylprednisolone.
Clinical research shows that grapefruit juice can increase the plasma concentration of orally administered methylprednisolone. Grapefruit juice 200 mL three times daily given with methylprednisolone 16 mg increased methylprednisolone half-life by 35%, peak plasma concentration by 27%, and total area under the curve by 75%.

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

Grapefruit juice can decrease levels of drugs that are substrates of OATP.
In vitro and clinical research show that consuming grapefruit juice inhibits OATP, which reduces the bioavailability of oral drugs that are substrates of OATP. Various clinical studies have shown reduced absorption of OATP substrates when taken with grapefruit, including fexofenadine, acebutolol, aliskiren, celiprolol, levothyroxine, nadolol, and pitavastatin. Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction.

Likelihood Likely Evidence B
Praziquantel (Biltricide)

Grapefruit juice can increase blood levels of praziquantel, potentially increasing the effects and adverse effects of praziquantel.
Clinical research shows that grapefruit juice can inhibit cytochrome P450 3A4 (CYP3A4) metabolism of praziquantel. Plasma concentrations of praziquantel can increase by as much as 160% when administered with 250 mL of commercially available grapefruit juice.

Likelihood Probable Evidence B
Qt Interval-Prolonging Drugs

Grapefruit or grapefruit juice, especially if consumed in large amounts, can cause additive QT interval prolongation when taken with QT interval-prolonging drugs, potentially increasing the risk of ventricular arrhythmias.
Clinical research in healthy volunteers shows that drinking 6 liters of grapefruit juice over 6 hours prolonged the QTc by a peak amount of 14 milliseconds (ms). This prolongation was similar to the QT prolongation caused by the drug moxifloxacin. In individuals with long QT syndrome, a smaller dose of grapefruit juice, 1.5 liters, resulted in a greater peak QTc prolongation of about 30 ms. The effect of smaller quantities of grapefruit juice on the QT interval is unclear.

Likelihood Probable Evidence B
Quetiapine (Seroquel)

Grapefruit juice may increase blood levels of quetiapine, increasing the effects and adverse effects of quetiapine.
Quetiapine is metabolized by cytochrome P450 3A4 (CYP3A4). Grapefruit can inhibit CYP3A4. In one case report, a healthy 28-year-old female with bipolar disorder stabilized on quetiapine 800 mg daily presented with quetiapine toxicity considered to be related to consuming a gallon of grapefruit juice over the past 24 hours.

Likelihood Probable Evidence B
Quinidine

Grapefruit juice can alter blood levels of quinidine, potentially increasing or decreasing the clinical effects of quinidine.
Clinical research shows that grapefruit juice decreases quinidine absorption, clearance, and metabolism, and prolongs the half-life by about 20%.

Likelihood Probable Evidence B
Grapefruit (Citrus paradisi) fruit extract full monograph & all 62 interactions

Echinacea12 drug types · 816 drugs

Caffeine

Echinacea can increase plasma levels of caffeine by inhibiting its metabolism.
Echinacea seems to increase plasma concentrations of caffeine by around 30%. This is likely due to inhibition of cytochrome P450 1A2 (CYP1A2) by echinacea.

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

Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Echinacea appears to inhibit CYP1A2 enzymes in humans. Additionally, echinacea seems to increase plasma concentrations of caffeine, a CYP1A2 substrate, by around 30%. Theoretically, echinacea might increase levels of other drugs metabolized by CYP1A2.

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

Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4. This may increase or decrease levels of drugs metabolized by CYP3A4.
Several clinical trials have shown that taking echinacea for up to one month does not significantly affect the metabolism of various CYP3A4 substrates, including midazolam, docetaxel, etravirine, lopinavir-ritonavir, and darunavir-ritonavir. However, other clinical research shows that echinacea may increase the clearance of midazolam, suggesting that echinacea might induce CYP3A4. The discrepancy is thought to be due to differing effects of echinacea on intestinal versus hepatic CYP3A4 enzymes. Echinacea appears to induce hepatic CYP3A4 but inhibit intestinal CYP3A4. In some cases, these effects might cancel each other out, but in others, drug levels may be increased or decreased depending on the level of effect at hepatic and intestinal sites. The effect of echinacea on CYP3A4 activity may differ depending on the CYP3A4 substrate.

Likelihood Possible Evidence B
Etoposide (Vepesid)

Echinacea may increase levels of etoposide.
In one report, concomitant use of etoposide and echinacea was associated with more severe thrombocytopenia than the use of etoposide alone, suggesting inhibition of etoposide metabolism. Etoposide is a cytochrome P450 3A4 (CYP3A4) substrate. Echinacea has variable effects on CYP3A4, but some studies have reported inhibition of the enzyme.

Likelihood Possible Evidence D
Immunosuppressants

Echinacea has immunostimulant activity which may interfere with immunosuppressant therapy.
Theoretically, echinacea may interfere with immunosuppressant therapy because of its immunostimulant activity.

Likelihood Possible Evidence B
Darunavir (Prezista)

Theoretically, echinacea may interfere with the metabolism of darunavir; however, a small clinical study found no effect.
Darunavir is metabolized by cytochrome P450 3A4 (CYP3A4) and is administered with the CYP3A4 inhibitor ritonavir to increase its plasma concentrations. Echinacea has variable effects on CYP3A4, but administration of an E. purpurea root extract (Arkocapsulas Echinacea, Arkopharma) 500 mg four times daily for 14 days did not affect darunavir/ritonavir pharmacokinetics in 15 HIV-infected patients.

Likelihood Unlikely Evidence B
Dayquil Severe

Echinacea is reported to have varying effects on a number of Cytochrome P450 metabolizing enzymes in the liver, including CYP1A2 and CYP3A4, which play a role in acetaminophen and dextromethorphan metabolism (both contained in DayQuil Severe), respectively. Studies have reported both enzyme inhibition and induction, making it difficult to predict clinically significant drug interactions with reliability. Specific drug interaction studies reporting definitive results are rare, and potential drug interactions involving echinacea should likely be taken on a case-by-case basis. Based on what we know about how acetaminophen and dextromethorphan are metabolized, the risk of a clinically significant interaction between echinacea and DayQuil Severe is low.

Likelihood Unlikely Evidence A
Docetaxel (Taxotere)

Theoretically, echinacea may interfere with the metabolism of docetaxel; however, a small clinical study found no effect.
Docetaxel is metabolized by cytochrome P450 3A4 (CYP3A4). Echinacea has variable effects on CYP3A4, but taking E. purpurea whole plant extract (Echinaforce, A. Vogel Biopharma AG) 20 drops three times daily for 2 weeks did not alter the pharmacokinetics of docetaxel in one clinical study.

Likelihood Unlikely Evidence B
Etravirine (Intelence)

Theoretically, echinacea may interfere with the metabolism of etravirine; however, a small clinical study found no effect.
Etravirine is metabolized by cytochrome P450 3A4 (CYP3A4). Echinacea has variable effects on CYP3A4, but taking E. purpurea root extract (Arkocapsulas Echinacea, Arkopharma) 500 mg three times daily for 14 days did not alter the pharmacokinetics of etravirine in HIV-infected patients.

Likelihood Unlikely Evidence B
Lopinavir/Ritonavir (Kaletra)

Theoretically, echinacea may interfere with the metabolism of lopinavir; however, a small clinical study found no effect.
Lopinavir is metabolized by cytochrome P450 3A4 (CYP3A4) and is administered with the CYP3A4 inhibitor ritonavir to increase its plasma concentrations. Echinacea has variable effects on CYP3A4, but taking E. purpurea (Echinamide, Natural Factors Nutritional Products, Inc.) 500 mg three times daily for 14 days did not alter the pharmacokinetics of lopinavir/ritonavir in healthy volunteers.

Likelihood Unlikely Evidence B
Midazolam (Versed)

Theoretically, echinacea may increase the metabolism of intravenous midazolam.
Echinacea induces hepatic CYP3A4 and might decrease plasma levels of midazolam by about 20%, reducing the effectiveness of intravenous midazolam. Echinacea also appears to inhibit intestinal CYP3A4, which could theoretically increase the bioavailability of oral midazolam. This may cancel out the decrease in availability caused by induction of hepatic CYP3A4, such that overall plasma levels after oral administration of midazolam are not affected by echinacea.

Likelihood Possible Evidence B
Warfarin (Coumadin)

Echinacea seems to increase the clearance of warfarin, although the effect may not be clinically significant.
Preliminary clinical research in healthy male volunteers suggests that taking echinacea increases the clearance of the active S-isomer of warfarin after a single dose of warfarin, but there was not a clinically significant effect on the INR.

Likelihood Possible Evidence B
Echinacea full monograph & interactions

Peppermint5 drug types · 796 drugs

Cyclosporine (Neoral, Sandimmune)

Theoretically, peppermint oil might increase the levels and adverse effects of cyclosporine.
In animal research, peppermint oil inhibits cyclosporine metabolism and increases cyclosporine levels. Inhibition of cytochrome P450 3A4 (CYP3A4) may be partially responsible for this interaction. An interaction between peppermint oil and cyclosporine has not been reported in humans.

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

Theoretically, peppermint might increase the levels of CYP2C19 substrates.
In vitro research shows that peppermint oil inhibits CYP2C19. So far, this interaction has not been reported in humans.

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

Theoretically, peppermint might increase the levels of CYP2C9 substrates.
In vitro research shows that peppermint oil inhibits CYP2C9. So far, this interaction has not been reported in humans.

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

Theoretically, peppermint might increase the levels of CYP3A4 substrates.
Clinical research in healthy volunteers shows that a single dose of peppermint oil 600 mg inhibits CYP3A4 enzymes and increases the AUC of felodipine, a CYP3A4 substrate. However, in vitro research suggests that peppermint oil only inhibits CYP3A4 at very high concentrations.

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

Theoretically, peppermint might increase the levels of CYP1A2 substrates.
In vitro and animal research shows that peppermint oil and peppermint leaf inhibit CYP1A2. However, in clinical research, peppermint tea did not significantly affect the metabolism of caffeine, a CYP1A2 substrate. It is possible that the 6-day duration of treatment may have been too short to identify a difference.

Likelihood Possible Evidence B
Peppermint full monograph & interactions
The maker

Brand information

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

Genestra Brands

Name
Seroyal USA
City
Pittsburgh
State
PA
ZipCode
15275
Phone Number
1-888-737-6925
Web Address
seroyal.com
Pharmacist Counseling Corner

Citrigen by Genestra Brands: Common Questions

Does Citrigen by Genestra Brands interact with any medications?
Yes. Based on its ingredients, Citrigen has a known interaction with 1,476 medications, including 785 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Citrigen contains 4 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take Citrigen if I'm pregnant or breastfeeding?
Green tea is rated possibly safe in pregnancy but also possibly unsafe—the data is mixed, so talk with your doctor or pharmacist. Peppermint is likely safe in pregnancy and lactation. Echinacea is possibly safe in pregnancy, but lactation data isn't on file. Grapefruit's pregnancy and lactation safety isn't documented in our data. Given these gaps and the medication interactions in this product, check with your healthcare provider before use.
What are the most common side effects I might experience?
Green tea most commonly causes bloating, constipation, diarrhea, nausea, and indigestion, especially at higher doses. Peppermint may cause abdominal pain, anal burning, belching, diarrhea, dry mouth, heartburn, nausea, or vomiting. Echinacea can trigger abdominal pain, constipation, diarrhea, heartburn, nausea, vomiting, or rashes. These effects are usually mild, but talk to your pharmacist if they persist.
Is Citrigen safe to take long-term?
Green tea extract seems well tolerated for up to 12 months. Peppermint and echinacea are generally well tolerated short-term, but long-term safety data is more limited—check with your pharmacist. Because of the medication interactions, regular monitoring by your healthcare provider is wise if you're taking Citrigen alongside prescriptions.
Will Citrigen help my immune system?
Echinacea is traditionally used for immune support, but our data shows insufficient reliable evidence to confirm it works for any specific condition, including infection or general immunity. The other ingredients don't have established immune-support claims in our data.
Can Citrigen help with digestion?
Peppermint in this product is likely effective for IBS and possibly effective for indigestion and related gastrointestinal discomfort. Green tea and grapefruit don't have established digestive claims in our data.
Are there any people who should definitely avoid Citrigen?
Anyone taking a beta-blocker, statin, seizure medication, heart medication, immunosuppressant, or ephedrine should check with their pharmacist first—interactions are documented and can be serious. People allergic to ragweed or related plants should avoid echinacea. If you're sensitive to caffeine or have a heart condition, the caffeine content in green tea may also be a concern.

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.

Citrigen label
Go deeper

The Full Monographs Behind Citrigen’s Ingredients

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

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 → Herb & supplement monograph

Peppermint

Interacts with 796 drugs

Peppermint is a popular herb with the best evidence supporting enteric-coated peppermint oil for easing IBS symptoms. It is generally well tolerated for most adults, but it can cause heartbu...

Read the full Peppermint monograph → Herb & supplement monograph

Echinacea

Interacts with 816 drugs

Echinacea is a popular herb taken to help prevent or shorten the common cold, but study results are mixed and the overall benefit appears small at best. It is generally well tolerated for sh...

Read the full Echinacea monograph → Herb & supplement monograph

Grapefruit

Interacts with 990 drugs

Grapefruit is a nutritious citrus fruit rich in vitamin C and other nutrients, and it is generally safe to eat. However, grapefruit is famous for serious interactions with many prescription...

Read the full Grapefruit monograph →
Sources

Sources & How We Checked

Citrigen'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 468 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.

Green Tea 219 references
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Grapefruit 157 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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