Major interaction on record — check this product against your medications before combining. Based on 2 of 3 ingredients. Check your meds →
Dietary supplement

Organic Earl Grey Loose Leaf Ingredients & Drug Interactions

by FGO

Organic Earl Grey Loose Leaf label
See full label image
Other (e.g. Tea Bag) 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 Organic Earl Grey Loose Leaf 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

Organic Earl Grey Loose Leaf is a dietary supplement by FGO with 3 active ingredients. Its ingredients are commonly taken for mental alertness and energy, heart health support, blood pressure and cholesterol.Based on those ingredients, 825 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Keemun Black Tea, Bergamot Oil. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Organic Earl Grey Loose Leaf by FGO

Ask about any prescription or over-the-counter medication and we check it for interactions with Organic Earl Grey Loose Leaf by FGO — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Organic Earl Grey Loose Leaf by FGO

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 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This blend contains 3 active ingredients: two black teas — Keemun and Assam — and bergamot oil, which gives Earl Grey its signature floral citrus note. Both black teas are the source of the product's caffeine content.

Bergamot oil is pressed from the rind of a citrus fruit and is a traditional flavoring in this tea style.

Does it work?

Couldn't assess
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 assessable

We hold no graded evidence for this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Healthy feels good.
  • Our graded evidence for these ingredients doesn't cover that particular purpose.

Black tea is likely effective for mental alertness — that's the caffeine at work. The blend is also possibly effective for heart attack (MI) prevention, bone strength (osteoporosis), low blood pressure, and ovarian cancer risk reduction, though the evidence for these is less established.

Bergamot in the mix is possibly effective for high cholesterol (hyperlipidemia), but we don't have enough reliable evidence yet to rate it for fatty liver disease or autism spectrum disorder.

The evidence, ingredient by ingredient Black Tea Bergamot

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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Black tea is generally well tolerated in moderate amounts by healthy adults, though high intake can cause problems. In moderate amounts, common side effects from the caffeine include jitteriness, insomnia, nausea, stomach irritation, rapid heartbeat, tremors, and increased urination.

Rare serious effects include irregular heartbeat and chest pain. Because caffeine passes into breast milk, keep your intake moderate if you're nursing — talk with your provider.

During pregnancy, limit caffeine intake; high amounts may be harmful, so stick to moderate tea consumption and check with your doctor. Bergamot oil, when used topically, can cause sun-related skin reactions and is possibly unsafe in pregnancy; there isn't enough safety data for breastfeeding, so it's safer to avoid it if you're nursing.

Side effects, ingredient by ingredient Black Tea Bergamot

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?
  • 2 of the 2 matched ingredients can interact with medications — Bergamot, Black Tea.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; lithium.
  • For scale: 825 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 you start this tea, double-check if you take ephedrine (a stimulant) — that's a Major concern and you'll want to avoid this combination. If you're on any of these medications, check with your pharmacist: blood thinners (warfarin), antiseizure drugs (valproate), diabetes medications, antipsychotics (clozapine), certain antidepressants (fluvoxamine), heartburn meds (cimetidine), alcohol-related drugs (disulfiram), or heart stress-test agents (dipyridamole).

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Major medication interactions have been identified, and safety information is well characterized.

If you love Earl Grey and don't take any of the medications listed above, this tea is a pleasant way to get a boost of mental alertness. But if you're on ephedrine, any blood thinner, diabetes medication, antipsychotic, or antidepressant, check with your pharmacist first — some of these interactions are serious.

Pregnant or breastfeeding? Talk to your provider about how much is safe for you.

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

Assessment coverage: 3 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Nov 22, 2024.

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 Organic Earl Grey Loose Leaf, straight from the product label.

Brand FGO
Barcode (UPC) X002BE4ZJB
Net contents 16 Ounce(s); 453 Gram(s)
Market status On market
Date entered into DSLD Nov 22, 2024
DSLD ID 321111
Product type Botanical
Supplement form Other (e.g. Tea Bag)
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Organic
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 Organic Earl Grey Loose Leaf by FGO, 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 Gram(s)
Maximum serving Sizes:
2 Gram(s)
Servings per container
226
UPC/BARCODE
X002BE4ZJB
IngredientAmount% DV
Calories0 Calorie(s)--
Keemun Black Tea1160 mg--
Assam Tea800 mg--
Bergamot Oil40 mg--

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

Brew 200 cups of tea

Measure 1 teaspoon of loose tea Add 8 oz fresh boiling water Steep tea for 4-5 minutes Smile, sip and feel good

While Earl Grey possesses the delicacy and nuance of flavor to be enjoyed on its own, it is also beautifully accentuated with a slice of lemon and pairs well with a buttery morning pastry. Our Earl Grey Tea can be enjoyed hot or cold, on its own or with a splash of milk and honey.

Formula

Loose Organic Tea

Savor the light and refreshing taste of our premium, loose Ear Grey tea. This blend unites the finest, full-bodied black teas from China and India, creating an exceptionally rich beverage, fermented to perfection, with a touch of citrusy bergamot oil from Italy.

This bag contains 16 oz of certified organic, loose leaf Earl Grey Tea. Italian Bergamot Oil Chinese Keemun Black tea Indian Assam Black tea

Fine Organic Tea: Chinese Black Keemun F.O.P. Tea and Indian Assam T.G.F.O.P. Tea. and Italian Bergamot Oil.

Caffeine: Experience a boost of sustainable energy from the naturally-occurring caffeine in this premium organic tea.

Formulation

Blended in USA A silky, full-bodied blend for the ultimate sipping experience

USDA Organic

Non GMO Project Verified nongmoproject.org

Custom servings: Our loose, organic tea allows you to customize each cup according to your sipping preference. Eco-conscious: No unnecessary waste from bags or strings. Just organic tea, ready to enjoy.

Certified Organic by: CCOF Certified Organic CCOF Organic is Non-GMO & more

Certified Organic CCOF Organic is Non-GMO & more

Seals/Symbols

USDA Organic Non GMO Project Verified nongmoproject.org

Certified Organic CCOF Organic is Non-GMO & more

General Statements

Healthy feels good

FGO products are sourced from nutrient dense origins around the world. We are committed to delivering the highest quality, certified organic products at a fair price, to help you live healthy and feel good. For recipes, giveaways and more visit us at www.FGOrganics.com

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.

Precautions

Consult with a healthcare provider prior to use if you are currently pregnant, nursing, taking medication, or if you have a medical condition.

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

See for yourself

Organic Earl Grey Loose Leaf by FGO label

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

Organic Earl Grey Loose Leaf 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 Organic Earl Grey Loose Leaf by FGO

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Gram(s) Dosage formOther (e.g. Tea Bag) Servings per container226 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.

Keemun Black Tea

Interacts with
694 drugs
1160 mg per serving Form: Camellia sinensis

Black tea is a popular caffeinated drink made from the fully oxidized leaves of the Camellia sinensis plant, and it contains caffeine and antioxidant...

Keemun Black Tea monograph & interactions

Assam Tea

Interacts with
694 drugs
800 mg per serving Form: Camellia sinensis

Black tea is a popular caffeinated drink made from the fully oxidized leaves of the Camellia sinensis plant, and it contains caffeine and antioxidant...

Assam Tea monograph & interactions

Bergamot Oil

Interacts with
410 drugs
40 mg per serving

Bergamot is a Mediterranean citrus fruit, and its standardized extract is most often used to support cholesterol and heart health, with some early but...

Bergamot Oil monograph & interactions
Interaction report

Organic Earl Grey Loose Leaf by FGO Drug Interactions

Want to check YOUR meds against Organic Earl Grey Loose Leaf?

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
825Drugs
8 Major 807 Moderate 10 Minor

Ingredients driving the most interactions

Keemun Black Tea 694
Bergamot Oil 410

Individual Drug Interactions

The ingredients in Organic Earl Grey Loose Leaf interact with 825 drugs. Click any drug to see the details.

2 of the 3 ingredients in Organic Earl Grey Loose Leaf interact with drugs. Each result below shows which ingredient is responsible. Keemun Black Tea Bergamot Oil

Each ingredient & the kinds of drugs it affects

For each ingredient in Organic Earl Grey Loose Leaf 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.

Keemun Black Tea46 drug types · 694 drugs

Ephedrine

Theoretically, concomitant use might increase the risk for simulant adverse effects.
Black 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. Tell patients to avoid taking caffeine with ephedrine and other stimulants.

Likelihood Probable Evidence D
Adenosine (Adenocard)

Theoretically, black tea might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Black tea contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. It is recommended that methylxanthines such as caffeine, as well as 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, black tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Black tea contains caffeine. Caffeine is reported to have antiplatelet activity. Theoretically, the caffeine in black tea might increase the risk of bleeding when used concomitantly with antiplatelet drugs. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Beta-Adrenergic Agonists

Theoretically, concomitant use of large amounts of black tea might increase cardiac inotropic effects of beta-agonists.
Black tea contains caffeine. Caffeine can increase cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Carbamazepine (Tegretol)

Theoretically, black tea might reduce the effects of carbamazepine and increase the risk for convulsion.
Black tea contains caffeine. Animal research suggests that 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 B
Cimetidine (Tagamet)

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

Likelihood Likely Evidence B
Clozapine (Clozaril)

Theoretically, black tea might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Concomitant administration of black tea and clozapine might theoretically cause acute exacerbation of psychotic symptoms due to the caffeine in black 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 black tea.
Black tea contains caffeine. Oral contraceptive drugs 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.
Black tea contains caffeine. Caffeine is metabolized by CYP1A2,. Theoretically, drugs that inhibit CYP1A2 may decrease the clearance rate of caffeine from black tea and increase caffeine levels.

Likelihood Possible Evidence D
Dipyridamole (Persantine)

Theoretically, black tea might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Black tea contains caffeine. Caffeine is a methylxanthine that may inhibit dipyridamole-induced vasodilation. It is recommended that methylxanthines such as caffeine, as well as methylxanthine-containing products such as black tea, 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.
Black tea contains caffeine. In human research, disulfiram decreases the clearance and increases the half-life of caffeine.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, using black tea with diuretic drugs might increase the risk of hypokalemia.
Black tea contains caffeine. Caffeine, especially in excessive amounts, 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.
Black tea contains caffeine. Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Ethosuximide (Zarontin)

Theoretically, black tea might reduce the effects of ethosuximide and increase the risk for convulsions.
Black 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 observed in humans.

Likelihood Possible Evidence D
Felbamate (Felbatol)

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

Likelihood Possible Evidence D
Flutamide (Eulexin)

Theoretically, black tea might increase the levels and adverse effects of flutamide.
Black 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 of adverse effects.

Likelihood Possible Evidence D
Fluvoxamine (Luvox)

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

Likelihood Probable Evidence B
Lithium

Theoretically, abrupt black tea withdrawal might increase the levels and adverse effects of lithium.
Black tea contains caffeine. Abrupt caffeine withdrawal can increase serum lithium levels. Two cases of lithium tremor that worsened with abrupt coffee withdrawal have been reported.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk of a hypertensive crisis.
Black tea contains caffeine. Caffeine has been shown to inhibit monoamine oxidase (MAO) A and B in laboratory studies. Concomitant intake of large amounts of caffeine with MAOIs might precipitate a hypertensive crisis. In a case report, a patient that consumed 10-12 cups of caffeinate coffee and took the MAOI tranylcypromine presented with severe hypertension. Hypertension was resolved after the patients switched to drinking decaffeinated coffee.

Likelihood Possible Evidence D
Nicotine

Theoretically, concomitant use might increase the risk of hypertension.
Black tea contains caffeine. Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly.

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

Theoretically, black tea might reduce the absorption of organic anion-transporting polypeptide (OATP) substrates.
In vitro, black tea extract inhibits organic anion-transporting polypeptide (OATP)2B1. OATP2B1 is expressed in the small intestine and liver and is responsible for the uptake of drugs and other compounds. In an animal model, black tea extract was found to inhibit the absorption of rosuvastatin, a substrate of OATP2B1. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

Theoretically, black tea might decrease the effects of pentobarbital.
Black tea contains caffeine. Theoretically, caffeine might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

Theoretically, black tea might reduce the effects of phenobarbital and increase the risk for convulsions.
Black tea contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenobarbital. The exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Phenylpropanolamine

Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.
Black tea contains caffeine. Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure. Phenylpropanolamine also seems to increase caffeine serum levels.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, black tea might reduce the effects of phenytoin and increase the risk for convulsions.
Black tea contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenytoin. The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Keemun Black Tea full monograph & all 46 interactions

Bergamot Oil2 drug types · 410 drugs

Antidiabetes Drugs

Theoretically, taking bergamot with antidiabetes drugs might increase the risk of hypoglycemia.
Animal research suggests that bergamot juice has hypoglycemic effects.

Likelihood Possible Evidence D
Photosensitizing Drugs

Theoretically, topical bergamot essential oil might increase the risk of side effects when used along with photosensitizing drugs.
Bergamot contains bergapten, which has photosensitizing effects.

Likelihood Probable Evidence D
Bergamot Oil full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Organic Earl Grey Loose Leaf, from the product label.

FGO

See all FGO products
Name
FGO
City
Seattle
State
WA
ZipCode
98117
Web Address
www.FGOrganics.com
Pharmacist Counseling Corner

Organic Earl Grey Loose Leaf by FGO: Common Questions

Does Organic Earl Grey Loose Leaf by FGO interact with any medications?
Yes. Based on its ingredients, Organic Earl Grey Loose Leaf has a known interaction with 825 medications, including 8 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Organic Earl Grey Loose Leaf contains 3 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.
Does this tea have caffeine?
Yes. Both the Keemun and Assam black teas contain caffeine, which is why this blend can help with mental alertness. If you're sensitive to caffeine or avoid it, this isn't the product for you.
Can I drink this if I'm pregnant or breastfeeding?
During pregnancy, the safety data advises keeping caffeine moderate — high intake may be harmful — so talk with your doctor about how much is safe for you. If you're breastfeeding, caffeine passes into breast milk and can affect your baby, so keep intake moderate and check with your provider.
What's bergamot oil and why is it in here?
Bergamot is a citrus fruit, and the oil from its rind gives Earl Grey its signature floral, slightly sweet flavor. It's also possibly effective for high cholesterol, though the evidence is still building.
What are the common side effects from drinking this tea?
Because of the caffeine, you might notice jitteriness, trouble sleeping, nausea, stomach upset, a faster heartbeat, tremors, or increased urination. These tend to happen with large amounts or in people sensitive to caffeine.
Is this tea safe to drink every day?
Moderate amounts of black tea are generally well tolerated by healthy adults. But if you drink very large amounts daily, the caffeine can cause problems — it's always a good idea to check with your pharmacist or doctor about what 'moderate' means for your situation.

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.

Organic Earl Grey Loose Leaf label
Go deeper

The Full Monographs Behind Organic Earl Grey Loose Leaf’s Ingredients

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

Herb & supplement monograph

Black Tea

Interacts with 694 drugs

Black tea is a popular caffeinated drink made from the fully oxidized leaves of the Camellia sinensis plant, and it contains caffeine and antioxidant plant compounds. Moderate tea drinking i...

Read the full Black Tea monograph → Herb & supplement monograph

Bergamot

Interacts with 410 drugs

Bergamot is a Mediterranean citrus fruit, and its standardized extract is most often used to support cholesterol and heart health, with some early but promising research. The essential oil i...

Read the full Bergamot monograph →
Sources

Sources & How We Checked

Organic Earl Grey Loose Leaf'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 167 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.

Black Tea 150 references
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  2. Hertog MGL, Sweetnam PM, Fehily AM, et al. Antioxidant flavonols and ischemic heart disease in a Welsh population of men: the Caerphilly Study. Am J Clin Nutr 1997;65:1489-94. PubMed
  3. Harder S, Fuhr U, Staib AH, Wolff T. Ciprofloxacin-caffeine: a drug interaction established using in vivo and in vitro investigations. Am J Med 1989;87:89S-91S. PubMed
  4. Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40. PubMed
  5. Healy DP, Polk RE, Kanawati L, et al. Interaction between oral ciprofloxacin and caffeine in normal volunteers. Antimicrob Agents Chemother 1989;33:474-8. PubMed
  6. Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37:348-50. PubMed
  7. Jefferson JW. Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988;49:72-3.
  8. Lasswell WL Jr, Weber SS, Wilkins JM. In vitro interaction of neuroleptics and tricylic antidepressants with coffee, tea, and gallotannic acid. J Pharm Sci 1984;73:1056-8. PubMed
  9. Kulhanek F, Linde OK, Meisenberg G. Precipitation of antipsychotic drugs in interaction with coffee or tea. Lancet 1979;2:1130.
  10. Merhav H, Amitai Y, Palti H, Godfrey S. Tea drinking and microcytic anemia in infants. Am J Clin Nutr 1985;41:1210-3.
  11. Joeres R, Klinker H, Heusler H, et al. Influence of mexiletine on caffeine elimination. Pharmacol Ther 1987;33:163-9. PubMed
  12. Vahedi K, Domingo V, Amarenco P, Bousser MG. Ischemic stroke in a sportsman who consumed MaHuang extract and creatine monohydrate for bodybuilding. J Neurol Neurosurg Psychiatr 2000;68:112-3.
  13. Wakabayashi K, Kono S, Shinchi K, et al. Habitual coffee consumption and blood pressure: A study of self-defense officials in Japan. Eur J Epidemiol 1998;14:669-73. PubMed
  14. Hodgson JM, Puddey IB, Burke V, et al. Effects on blood pressure of drinking green and black tea. J Hypertens 1999;17:457-63. PubMed
  15. Rapuri PB, Gallagher JC, Kinyamu HK, Ryschon KL. Caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes. Am J Clin Nutr 2001;74:694-700. PubMed
  16. The National Toxicology Program (NTP). Caffeine. Center for the Evaluation of Risks to Human Reproduction (CERHR). Available at: http://cerhr.niehs.nih.gov/common/caffeine.html.
  17. Klebanoff MA, Levine RJ, DerSimonian R, et al. Maternal serum paraxanthine, a caffeine metabolite, and the risk of spontaneous abortion. N Engl J Med 1999;341:1639-44. PubMed
  18. Eskenazi B. Caffeine—filtering the facts. N Engl J Med 1999;341:1688-9. PubMed
  19. Fernandes O, Sabharwal M, Smiley T, et al. Moderate to heavy caffeine consumption during pregnancy and relationship to spontaneous abortion and abnormal fetal growth: a meta-analysis. Reprod Toxicol 1998;12:435-44. PubMed
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See these in context on the Black Tea monograph →

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See these in context on the Bergamot monograph →

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

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