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Dietary supplement

Oolong Tea Extract Ingredients & Drug Interactions

by BulkSupplements.com

Oolong Tea Extract label
See full label image
Powder Category: Botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Oolong Tea Extract 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

Oolong Tea Extract is a dietary supplement by BulkSupplements.com with 1 active ingredient. Its ingredients are commonly taken for weight management, mental alertness and energy, heart health.Based on those ingredients, 652 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Oolong Tea Leaf Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Oolong Tea Extract by BulkSupplements.com

Ask about any prescription or over-the-counter medication and we check it for interactions with Oolong Tea Extract by BulkSupplements.com — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Oolong Tea Extract by BulkSupplements.com

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: oolong tea leaf extract. Oolong tea is a traditional beverage made from tea plant leaves that gives you the caffeine content you'd get from a cup of tea.

There are no inactive fillers or other ingredients in this powder.

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 Oolong Tea's overall clinical evidence instead.

Strong

Strong clinical evidence supports Oolong Tea 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 ingredient's overall clinical evidence instead.
  • On file: Mental alertness — rated "Likely Effective" (Natural Medicines).

Oolong tea is likely effective for mental alertness — that's the caffeine doing its job. For other uses listed here — autism spectrum disorder, osteoporosis, oral cancer, and chronic obstructive pulmonary disease (COPD) — the evidence we hold is insufficient to rate whether oolong tea works.

The evidence, ingredient by ingredient Oolong Tea

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 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Oolong tea is generally well tolerated in moderate amounts. Most side effects come from its caffeine content: insomnia, jitteriness, restlessness, a fast heartbeat, and tremors are common.

Rare serious effects tied to caffeine include irregular heartbeat, chest pain, and seizures. Some people may have a caffeine sensitivity that causes anaphylaxis, though true caffeine allergy is uncommon.

During pregnancy, the safety data is mixed — some evidence says possibly safe, other evidence says possibly unsafe. Talk with your doctor about whether regular use is right for you.

Caffeine passes into breast milk; if you're nursing, keep your intake low and watch your baby for fussiness or irritability.

Side effects, ingredient by ingredient Oolong Tea

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?
  • 1 of the 1 matched ingredient can interact with medications — Oolong Tea.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; lithium.
  • For scale: 652 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 product, double-check with your pharmacist if you take ephedrine or any stimulant (Major risk). Also flag any heart medications, seizure medications, antipsychotics like clozapine, acid reflux drugs like cimetidine, antabuse (disulfiram), or barbiturates — these all have documented Moderate interactions with the caffeine in oolong tea.

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.

Oolong tea extract is a straightforward source of caffeine for mental alertness, generally well tolerated in moderate amounts. If you take any prescription medications — especially stimulants like ephedrine, heart medications, seizure drugs, antipsychotics, or acid reflux or alcohol-dependence medications — you need to check your exact drugs before starting this product.

Talk to your pharmacist or doctor, especially if you're pregnant, nursing, or have a heart condition.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated May 23, 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 Oolong Tea Extract, straight from the product label.

Brand BulkSupplements.com
Barcode (UPC) X001HZJRY3
Net contents 1 Kilogram(s); 35.3 Ounce(s)
Market status On market
Date entered into DSLD May 23, 2024
DSLD ID 312833
Product type Botanical
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, 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 Oolong Tea Extract by BulkSupplements.com, 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:
500 mg
Maximum serving Sizes:
500 mg
Servings per container
2000
UPC/BARCODE
X001HZJRY3
IngredientAmount% DV
Oolong Tea Leaf Extract500 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.
Brand IP Statement(s)

Bulksupplements.com Clean & pure bulk supplements

Formulation

Free of: Added sugar, soy, dairy, yeast, gluten, additives

Color may vary.

Precautions

Suggested Use: As a dietary supplement, take 500 mg (about 1/5 tsp) once or twice daily, or as directed by a physician.

Keep out of reach of children.

Always consult a physician before taking any dietary supplement.

General Statements

Use an accurate milligram scale.

New

Storage

Contents are sold by weight, not volume. Settling may occur. Store in a dry, cool place

FDA Disclaimer Statement

Warning: 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

Oolong Tea Extract by BulkSupplements.com label

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

Oolong Tea Extract 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 Oolong Tea Extract by BulkSupplements.com

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size500 mg Dosage formPowder Servings per container2000 Amounts shown are per serving.

Oolong Tea Leaf Extract

Interacts with
652 drugs
500 mg per serving

Oolong tea is a traditional partially oxidized tea made from the same plant as green and black tea, and it provides caffeine and plant antioxidants. A...

Oolong Tea Leaf Extract monograph & interactions
Interaction report

Oolong Tea Extract by BulkSupplements.com Drug Interactions

Want to check YOUR meds against Oolong Tea Extract?

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
652Drugs
8 Major 518 Moderate 126 Minor

Ingredients driving the most interactions

Oolong Tea Leaf Extract 652

Individual Drug Interactions

The ingredients in Oolong Tea Extract interact with 652 drugs. Click any drug to see the details.

1 of the 1 ingredient in Oolong Tea Extract interact with drugs. Each result below shows which ingredient is responsible. Oolong Tea Leaf Extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Oolong Tea Extract with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Oolong Tea Leaf Extract37 drug types · 652 drugs

Ephedrine

Theoretically, concomitant use might increase the risk for stimulant adverse effects.
Oolong 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, oolong tea might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Oolong 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, oolong tea might increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Oolong tea contains caffeine. Caffeine is reported to have antiplatelet activity. Theoretically, the caffeine in oolong tea might increase the risk of bleeding when used concomitantly with these agents. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Beta-Adrenergic Agonists

Theoretically, large amounts of oolong tea might increase the cardiac inotropic effects of beta-agonists.
Oolong tea contains caffeine. Caffeine can increase cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Cimetidine (Tagamet)

Theoretically, concomitant use might increase the effects and adverse effects of caffeine in oolong tea.
Oolong tea contains caffeine. Cimetidine can reduce the rate of caffeine clearance by 30% to 50%.

Likelihood Likely Evidence B
Clozapine (Clozaril)

Theoretically, oolong tea might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Oolong tea contains caffeine. Caffeine can increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg per day 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
Cytochrome P450 1A2 (Cyp1A2) Inhibitors

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

Likelihood Possible Evidence D
Dipyridamole (Persantine)

Theoretically, oolong tea might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Oolong 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 oolong tea, be stopped 24 hours prior to pharmacological stress tests. Methylxanthines appear more likely to interfere with dipyridamole than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram might increase the risk of adverse effects from caffeine in oolong tea.
Oolong tea contains caffeine. Disulfiram decreases the clearance and increases the half-life of caffeine.

Likelihood Probable Evidence D
Diuretic Drugs

Theoretically, using oolong tea with diuretic drugs might increase the risk of hypokalemia.
Oolong 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 in oolong tea.
Oolong tea contains caffeine. Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Flutamide (Eulexin)

Theoretically, oolong tea might increase the levels and adverse effects of flutamide.
Oolong tea contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide.

Likelihood Possible Evidence D
Fluvoxamine (Luvox)

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

Likelihood Probable Evidence D
Lithium

Theoretically, abrupt oolong tea withdrawal might increase the levels and adverse effects of lithium.
Oolong tea contains caffeine. Abrupt caffeine withdrawal can increase serum lithium levels, worsening lithium tremor.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk of a hypertensive crisis.
Oolong tea contains caffeine. Caffeine has been shown to inhibit MAO A and B in laboratory studies. Concomitant intake of large amounts of caffeine with MAOIs might precipitate a hypertensive crisis.

Likelihood Possible Evidence D
Nicotine

Theoretically, concomitant use might increase the risk of hypertension.
Oolong 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 D
Pentobarbital (Nembutal)

Theoretically, caffeine in oolong tea might decrease the effects of pentobarbital.
Oolong tea contains caffeine. The caffeine in oolong tea might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

Theoretically, oolong tea might reduce the effects of phenobarbital and increase the risk for convulsions.
Oolong 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 in oolong tea.
Oolong 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, oolong tea might reduce the effects of phenytoin and increase the risk for convulsions.
Oolong 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
Pioglitazone (Actos)

Theoretically, oolong tea might increase the levels and clinical effects of pioglitazone.
Oolong tea contains caffeine. Animal research suggests that caffeine can modestly increase the maximum concentration, area under the curve, and half-life of pioglitazone, and also reduce its clearance. This increased the antidiabetic effects of pioglitazone. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Riluzole (Rilutek)

Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.
Oolong tea contains caffeine. Caffeine and riluzole are both metabolized by cytochrome P450 1A2 (CYP1A2), and concomitant use might reduce metabolism of one or both agents.

Likelihood Possible Evidence D
Stimulant Drugs

Theoretically, concomitant use might increase stimulant adverse effects.
Oolong tea contains caffeine. Due to the CNS stimulant effects of the caffeine constituent of oolong tea, concomitant use with stimulant drugs can increase the risk of adverse effects.

Likelihood Probable Evidence C
Theophylline

Theoretically, oolong tea might increase the levels and adverse effects of theophylline.
Oolong tea contains caffeine. Caffeine decreases theophylline clearance 23% to 29%.

Likelihood Probable Evidence D
Valproate

Theoretically, oolong tea might reduce the effects of valproate and increase the risk for convulsions.
Oolong tea contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of valproate. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Oolong Tea Leaf Extract full monograph & all 37 interactions
The maker

Brand information

Manufacturer and brand details for Oolong Tea Extract, from the product label.

BulkSupplements.com

See all BulkSupplements.com products
Name
BulkSupplements.com
Street Address
7511 Eastgate Rd
City
Henderson
State
NV
ZipCode
89011
Web Address
BulkSupplements.com
Pharmacist Counseling Corner

Oolong Tea Extract by BulkSupplements.com: Common Questions

Does Oolong Tea Extract by BulkSupplements.com interact with any medications?
Yes. Based on its ingredients, Oolong Tea Extract has a known interaction with 652 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?
Oolong Tea Extract contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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 give me the same caffeine as a cup of oolong tea?
Yes — this extract comes from oolong tea leaves, so it delivers caffeine much the same way the beverage does.
Can I take this while I'm pregnant?
The safety data is unclear — some evidence suggests it's possibly safe, and some suggests possibly unsafe. Talk with your doctor before regular use so you can decide together what's right for you.
What are the common side effects?
Most side effects come from caffeine: insomnia, nervousness, restlessness, a fast heartbeat, and tremors. These usually happen with moderate to higher intakes.
Is oolong tea extract effective for anything besides alertness?
Oolong tea is likely effective for mental alertness. For autism, osteoporosis, oral cancer, and COPD, we don't have enough reliable evidence to say whether it works.
Can I use this while breastfeeding?
Caffeine does pass into breast milk. The safety rating is possibly safe, but you should keep your intake low and watch your baby for fussiness. Check with your pharmacist or doctor for personalized guidance.

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.

Oolong Tea Extract label
Go deeper

The Full Monographs Behind Oolong Tea Extract’s Ingredients

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

Herb & supplement monograph

Oolong Tea

Interacts with 652 drugs

Oolong tea is a traditional partially oxidized tea made from the same plant as green and black tea, and it provides caffeine and plant antioxidants. As a beverage it is generally considered...

Read the full Oolong Tea monograph →
Sources

Sources & How We Checked

Oolong Tea Extract'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 112 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.

Oolong Tea 112 references
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  2. 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
  3. Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40. PubMed
  4. 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
  5. Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37:348-50. PubMed
  6. Jefferson JW. Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988;49:72-3.
  7. Merhav H, Amitai Y, Palti H, Godfrey S. Tea drinking and microcytic anemia in infants. Am J Clin Nutr 1985;41:1210-3.
  8. Joeres R, Klinker H, Heusler H, et al. Influence of mexiletine on caffeine elimination. Pharmacol Ther 1987;33:163-9. PubMed
  9. 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.
  10. 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
  11. 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
  12. 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
  13. 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.
  14. 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
  15. Eskenazi B. Caffeine—filtering the facts. N Engl J Med 1999;341:1688-9. PubMed
  16. 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
  17. Pollock BG, Wylie M, Stack JA, et al. Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women. J Clin Pharmacol 1999;39:936-40. PubMed
  18. DiPiro JT, Talbert RL, Yee GC, et al; eds. Pharmacotherapy: A pathophysiologic approach. 4th ed. Stamford, CT: Appleton & Lange, 1999.
  19. Nurminen ML, Niittynen L, Korpela R, Vapaatalo H. Coffee, caffeine and blood pressure: a critical review. Eur J Clin Nutr 1999;53:831-9. PubMed
  20. Dews PB, Curtis GL, Hanford KJ, O'Brien CP. The frequency of caffeine withdrawal in a population-based survey and in a controlled, blinded pilot experiment. J Clin Pharmacol 1999;39:1221-32. PubMed
  21. FDA. Proposed rule: dietary supplements containing ephedrine alkaloids. Available at: www.verity.fda.gov (Accessed 25 January 2000).
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  23. Briggs GB, Freeman RK, Yaffe SJ. Drugs in Pregnancy and Lactation. 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 1998.
  24. Hagg S, Spigset O, Mjorndal T, Dahlqvist R. Effect of caffeine on clozapine pharmacokinetics in healthy volunteers. Br J Clin Pharmacol 2000;49:59-63. PubMed
  25. Watson JM, Jenkins EJ, Hamilton P, et al. Influence of caffeine on the frequency and perception of hypoglycemia in free-living patients with type 1 diabetes. Diabetes Care 2000;23:455-9. PubMed
  26. Lloyd T, Johnson-Rollings N, Eggli DF, et al. Bone status among postmenopausal women with different habitual caffeine intakes: a longitudinal investigation. J Am Coll Nutr 2000;19:256-61. PubMed
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  29. Haller CA, Benowitz NL. Adverse cardiovascular and central nervous system events associated with dietary supplements containing ephedra alkaloids. N Engl J Med 2000;343:1833-8. PubMed
  30. Ferrini RL, Barrett-Connor E. Caffeine intake and endogenous sex steroid levels in postmenopausal women. The Rancho Bernardo Study. Am J Epidemiol 1996:144:642-4. PubMed
  31. Bell DG, Jacobs I, Ellerington K. Effect of caffeine and ephedrine ingestion on anaerobic exercise performance. Med Sci Sports Exerc 2001;33:1399-403. PubMed
  32. Horner NK, Lampe JW. Potential mechanisms of diet therapy for fibrocystic breast conditions show inadequate evidence of effectiveness. J Am Diet Assoc 2000;100:1368-80. PubMed
  33. Bracken MB, Triche EW, Belanger K, et al. Association of maternal caffeine consumption with decrements in fetal growth. Am J Epidemiol 2003;157:456-66.. PubMed
  34. McGowan JD, Altman RE, Kanto WP Jr. Neonatal withdrawal symptoms after chronic maternal ingestion of caffeine. South Med J 1988;81:1092-4.. PubMed
  35. Massey LK. Is caffeine a risk factor for bone loss in the elderly? Am J Clin Nutr 2001;74:569-70. PubMed
  36. Dreher HM. The effect of caffeine reduction on sleep quality and well-being in persons with HIV. J Psychosom Res 2003;54:191-8.. PubMed
  37. Kockler DR, McCarthy MW, Lawson CL. Seizure activity and unresponsiveness after hydroxycut ingestion. Pharmacotherapy 2001;21:647-51.. PubMed
  38. Schechter MD, Timmons GD. Objectively measured hyperactivity--II. Caffeine and amphetamine effects. J Clin Pharmacol 1985;25:276-80.. PubMed
  39. Nix D, Zelenitsky S, Symonds W, et al. The effect of fluconazole on the pharmacokinetics of caffeine in young and elderly subjects. Clin Pharmacol Ther 1992;51:183. DOI
  40. Infante S, Baeza ML, Calvo M, et al. Anaphylaxis due to caffeine. Allergy 2003;58:681-2. PubMed
  41. Massey LK, Whiting SJ. Caffeine, urinary calcium, calcium metabolism and bone. J Nutr 1993;123:1611-4. PubMed
  42. Nawrot P, Jordan S, Eastwood J, et al. Effects of caffeine on human health. Food Addit Contam 2003;20:1-30. PubMed
  43. May DC, Jarboe CH, VanBakel AB, Williams WM. Effects of cimetidine on caffeine disposition in smokers and nonsmokers. Clin Pharmacol Ther 1982;31:656-61. PubMed
  44. Abernethy DR, Todd EL. Impairment of caffeine clearance by chronic use of low-dose oestrogen-containing oral contraceptives. Eur J Clin Pharmacol 1985;28:425-8. PubMed
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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