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Dietary supplement

Evening Primrose Oil 500 mg Cold-Pressed Ingredients & Drug Interactions

by Quest

Evening Primrose Oil 500 mg Cold-Pressed label
See full label image
Softgel Capsule Category: Botanical With Nutrients
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Evening Primrose Oil 500 mg Cold-Pressed 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: Moderate

Evening Primrose Oil 500 mg Cold-Pressed is a dietary supplement by Quest with 2 active ingredients. Its ingredients are commonly taken for general antioxidant support, skin and hair care, heart health.Based on those ingredients, 833 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Vitamin E, Evening Primrose (Oenothera biennis) seed 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 Evening Primrose Oil 500 mg Cold-Pressed by Quest

Ask about any prescription or over-the-counter medication and we check it for interactions with Evening Primrose Oil 500 mg Cold-Pressed by Quest — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Evening Primrose Oil 500 mg Cold-Pressed by Quest

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.
  • “Evening Primrose (Oenothera biennis) seed oil” is listed as a grouped ingredient — the label gives one combined amount (500 mg) without saying how much of each component you get.

This softgel contains 3 active ingredients. Vitamin E is an antioxidant vitamin that supports cell health and is used to treat vitamin E deficiency and certain related conditions.

The other two active ingredients are gamma-linolenic acid and linoleic acid, which are fatty acids found in evening primrose oil. The capsules also contain gelatin and glycerin as inactive ingredients to hold everything together.

Does it work?

Moderate 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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: Essential fatty acids for health maintenance.
  • We looked for evidence on: Atopic dermatitis (eczema), Aging skin, Dry skin, Mastalgia, Dysmenorrhea, Menopausal symptoms — and 4 related terms.
  • The strongest evidence on file: Vitamin E is rated "Possibly Effective" for Dysmenorrhea (Natural Medicines).
  • Also on file: Vitamin E is rated "Possibly Ineffective" for Atopic dermatitis (eczema).
  • Also on file: Vitamin E is rated "Insufficient Reliable Evidence To Rate" for Aging skin, Diabetic neuropathy, Menopausal symptoms.

Vitamin E is established as effective for treating vitamin E deficiency itself and ataxia with vitamin E deficiency (AVED), a rare neurological condition. It's considered possibly effective for Alzheimer disease, beta-thalassemia, glucose-6-phosphate dehydrogenase (G6PD) deficiency, and intracranial hemorrhage.

We don't have effectiveness data in our records for the other ingredients in this product.

The evidence, ingredient by ingredient Vitamin E Evening Primrose

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.

Vitamin E is generally well-tolerated at usual dietary amounts, but high-dose long-term supplements carry caution. High doses may increase the risk of bleeding, and there is some concern about a higher risk of hemorrhagic stroke in male smokers taking synthetic vitamin E for extended periods, though other studies haven't consistently shown this.

Serious adverse effects are rare but can include bleeding and cardiovascular complications. For pregnancy, vitamin E from food and prenatal vitamins is appropriate, but avoid high-dose supplements unless your doctor directs you to.

While breastfeeding, normal dietary amounts are fine, but check with your doctor before taking high-dose supplements. We don't have pregnancy or breastfeeding safety data on file for gamma-linolenic acid or linoleic acid.

Side effects, ingredient by ingredient Vitamin E Evening Primrose

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Vitamin E.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; cancer treatments.
  • For scale: 765 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check with your pharmacist if you're on blood thinners or antiplatelet drugs (moderate risk of increased bleeding), chemotherapy drugs like cyclophosphamide or doxorubicin (moderate risk of reduced effectiveness), medications metabolized by your liver's CYP3A4 system (moderate risk of lower drug levels), selumetinib for cancer (moderate risk of excess vitamin E and bleeding), cyclosporine for transplant or autoimmune conditions (moderate risk of higher cyclosporine levels), or niacin for cholesterol (minor risk of reduced cholesterol benefits).

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This product is worth considering if you're looking to supplement evening primrose oil, but vitamin E does interact with blood thinners, some chemotherapy drugs, and other medications. If you take any prescription drugs—especially anticoagulants, cancer treatments, or cyclosporine—run them through the checker below before you start.

Your pharmacist can help you figure out whether the dose in this product is safe alongside your current medications.

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

Assessment coverage: 1 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jul 25, 2013.

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 Evening Primrose Oil 500 mg Cold-Pressed, straight from the product label.

Brand Quest
Barcode (UPC) 058371212249
Net contents 120 Softgel(s)
Market status Off market
Date entered into DSLD Jul 25, 2013
DSLD ID 24007
Product type Botanical With Nutrients
Supplement form Softgel Capsule
Dietary claims / uses All Other
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 Evening Primrose Oil 500 mg Cold-Pressed by Quest, 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:
3 Softgel(s)
Maximum serving Sizes:
6 Softgel(s)
UPC/BARCODE
058371212249
IngredientAmount% DV
Vitamin E14.9 IU--
Gamma-Linolenic Acid50 mg--
Linoleic Acid360 mg--
Evening Primrose (Oenothera biennis) seed oil500 mg--

Other ingredients: Gelatin, Glycerin

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 Use: A source of essential fatty acids for the maintenance of good health. Recommended Dose (Adults): Take 3 to 6 softgels daily with meals.

Formulation

This product does not contain corn, dairy, egg, gluten, shellfish, sulfites or wheat.

No artificial colours, flavours or preservatives

Storage

STORE IN A COOL, DRY PLACE.

Precautions

KEEP OUT OF REACH OF CHILDREN.

DO NOT USE IF SEAL UNDER CAP IS BROKEN.

General Statements

OMEGA

Source of omega-6 essential fatty acids

A Proud Canadian Company

Seals/Symbols

PREMIUM - QUALITY ASSURED

{Recycle}

SunOpta A healthy products company

General

338340.01-04

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

See for yourself

Evening Primrose Oil 500 mg Cold-Pressed by Quest label

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

Evening Primrose Oil 500 mg Cold-Pressed 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 Evening Primrose Oil 500 mg Cold-Pressed by Quest

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size3 Softgel(s) Dosage formSoftgel Capsule 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.

Vitamin E

Interacts with
764 drugs
14.9 IU per serving Form: D-Alpha-Tocopherol

Vitamin E is an essential fat-soluble vitamin and antioxidant that most people get in adequate amounts from a normal diet. Supplements can help correc...

Vitamin E monograph & interactions

Evening Primrose (Oenothera biennis) seed oil

Interacts with
233 drugs
500 mg per serving

Evening primrose oil is a seed oil rich in gamma-linolenic acid (GLA), an omega-6 fatty acid, that is popularly used for skin conditions, PMS, and bre...

Evening Primrose (Oenothera biennis) seed oil monograph & interactions
  • › Gamma-Linolenic Acid
  • › Linoleic Acid

Other (inactive) ingredients: Gelatin, Glycerin. These complete the product’s ingredient list but are not active constituents.

Interaction report

Evening Primrose Oil 500 mg Cold-Pressed by Quest Drug Interactions

Want to check YOUR meds against Evening Primrose Oil 500 mg Cold-Pressed?

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
833Drugs
781 Moderate 52 Minor

Ingredients driving the most interactions

Vitamin E 764
Evening Primrose (Oenothera biennis) seed oil 233

Individual Drug Interactions

The ingredients in Evening Primrose Oil 500 mg Cold-Pressed interact with 833 drugs. Click any drug to see the details.

2 of the 2 ingredients in Evening Primrose Oil 500 mg Cold-Pressed interact with drugs. Each result below shows which ingredient is responsible. Vitamin E Evening Primrose (Oenothera biennis) seed oil

Each ingredient & the kinds of drugs it affects

For each ingredient in Evening Primrose Oil 500 mg Cold-Pressed 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.

Vitamin E8 drug types · 764 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin E might reduce the effectiveness of alkylating agents.
There's concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin E have on chemotherapy. Advise patients to consult their oncologist before using vitamin E supplements, especially in high doses.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Concomitant use of vitamin E and anticoagulant or antiplatelet agents might increase the risk of bleeding.
Vitamin E seems to inhibit of platelet aggregation and antagonize the effects of vitamin K-dependent clotting factors. These effects appear to be dose-dependent, and are probably only likely to be clinically significant with doses of at least 800 units daily. Mixed tocopherols, such as those found in food, might have a greater antiplatelet effect than alpha-tocopherol. RRR alpha-tocopherol (natural vitamin E) 1000 IU daily antagonizes vitamin K-dependent clotting factors. Advise patients to avoid high doses of vitamin E, especially in people with low vitamin K intake or other risk factors for bleeding.

Likelihood Possible Evidence B
Antitumor Antibiotics

Theoretically, antioxidant effects of vitamin E might reduce the effectiveness of antitumor antibiotics.
There's concern that antioxidants could reduce the activity of antitumor antibiotic drugs such as doxorubicin, which generate free radicals. However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin E have on chemotherapy involving antitumor antibiotics. Advise patients to consult their oncologist before using vitamin E supplements, especially in high doses.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

A specific form of vitamin E might increase absorption and levels of cyclosporine.
There is some evidence that one specific formulation of vitamin E (D-alpha-tocopheryl-polyethylene glycol-1000 succinate, TPGS, tocophersolan, Liqui-E) might increase absorption of cyclosporine. This vitamin E formulation forms micelles which seems to increase absorption of cyclosporine by 40% to 72% in some patients. However, this interaction is unlikely to occur with the usual forms of vitamin E.

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

Theoretically, vitamin E might induce metabolism of CYP3A4, possibly reducing the levels CYP3A4 substrates.
Vitamin E appears to bind with the nuclear receptor, pregnane X receptor (PXR), which results in increased expression of CYP3A4. Although the clinical significance of this is not known, use caution when considering concomitant use of vitamin E and other drugs affected by these enzymes.

Likelihood Possible Evidence D
Selumetinib (Koselugo)

Taking selumetinib with vitamin E can result in a total daily dose of vitamin E that exceeds safe limits and therefore might increase the risk of bleeding.
Selumetinib contains 48-54 IU vitamin E per capsule. The increased risk of bleeding with vitamin E appears to be dose-dependent. Be cautious when using selumetinib in combination with supplemental vitamin E, especially in patients at higher risk of bleed, such as those with chronic conditions and those taking antiplatelet drugs.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Using vitamin E with warfarin might increase the risk of bleeding.
Due to interference with production of vitamin K-dependent clotting factors, use of more than 400 IU of vitamin E daily with warfarin might increase prothrombin time (PT), INR, and the risk of bleeding,. At a dose of 1000 IU per day, vitamin E can antagonize vitamin K-dependent clotting factors even in people not taking warfarin. Limited clinical evidence suggests that doses up to 1200 IU daily may be used safely by patients taking warfarin, but this may not be applicable in all patient populations.

Likelihood Possible Evidence B
Niacin

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

Likelihood Possible Evidence A
Vitamin E full monograph & interactions

Evening Primrose (Oenothera biennis) seed oil5 drug types · 233 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Evening primrose oil contains gamma linolenic acid (GLA). There is preliminary clinical evidence that GLA can reduce platelet aggregation and prolong bleeding time.

Likelihood Possible Evidence D
Lithium

Theoretically, concomitant use of lithium with evening primrose oil might decrease lithium levels and effects.
In a case report, a patient on a stable dose of lithium for 10 years experienced a reduction in lithium levels after taking evening primrose oil 500 mg daily. Baseline levels were 0.69 mmol/L, which decreased to 0.37 mmol/L after 2 months and 0.23 mmol/L after 3 months of use. Lithium levels increased within 6 weeks of discontinuing evening primrose oil, to 0.73 mmol/L; no clinical effects were noted.

Likelihood Possible Evidence D
Lopinavir/Ritonavir (Kaletra)

Theoretically, evening primrose oil might increase the levels and effects of lopinavir.
In a case report, an HIV patient who took evening primrose oil (Efamol) along with lopinavir/ritonavir experienced an increase in serum levels of lopinavir to 15.2 mg/L. Six weeks after discontinuing evening primrose oil, levels of lopinavir returned to the normal range of 5-10 mg/L. When re-challenged with evening primrose oil for a week, the patient's lopinavir levels increased from 6.69 to 8.11 mg/L. It is suspected that evening primrose oil increases levels of lopinavir by inhibiting cytochrome P450 3A4 (CYP3A4), which metabolizes lopinavir. However, this effect has not been reported in other research.

Likelihood Possible Evidence D
Phenothiazines

Theoretically, taking evening primrose oil with phenothiazines might increase the risk of convulsions.
Evening primrose oil contains gamma-linolenic acid (GLA). There is some concern that taking supplements containing GLA might cause seizures, or lower the seizure threshold, when taken with phenothiazines. In one report, three patients with schizophrenia who had received phenothiazines developed EEG changes suggestive of temporal lobe epilepsy after starting treatment with GLA, although none experienced an actual seizure. In another report, two patients with schizophrenia who were stabilized on phenothiazines developed seizures when evening primrose oil 4 grams daily was added. One of these patients had a prior history of seizures. It is unclear whether evening primrose oil had any additive epileptogenic effects with the phenothiazines; there is no evidence that taking evening primrose oil alone causes seizures.

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

Theoretically, evening primrose may increase the levels and clinical effects of CYP2C9 substrates.
In vitro research shows that linoleic acid, a constituent of evening primrose oil, inhibits CYP2C9.

Likelihood Possible Evidence D
Evening Primrose (Oenothera biennis) seed oil full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Evening Primrose Oil 500 mg Cold-Pressed, from the product label.

Quest

See all Quest products
Name
SunOpta Inc.
Street Address
6 Commerce Crescent
City
Acton
State
ON
ZipCode
L7J 2X3
Pharmacist Counseling Corner

Evening Primrose Oil 500 mg Cold-Pressed by Quest: Common Questions

Does Evening Primrose Oil 500 mg Cold-Pressed by Quest interact with any medications?
Yes. Based on its ingredients, Evening Primrose Oil 500 mg Cold-Pressed has a known interaction with 833 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Evening Primrose Oil 500 mg Cold-Pressed contains 2 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Will this help with high cholesterol or heart health?
We don't have effectiveness data for evening primrose oil on cholesterol or heart health in our records. Vitamin E alone is established for treating vitamin E deficiency, but that's different from using it as a general supplement for heart or cholesterol support. Talk with your pharmacist or doctor about whether this product fits your health goals.
Can I take this if I'm pregnant or breastfeeding?
Vitamin E from food and prenatal vitamins is safe in pregnancy, but avoid high-dose supplements unless your doctor says otherwise. While breastfeeding, normal dietary amounts are fine, but check with your doctor before taking high-dose supplements. We don't have safety data on file for the other ingredients during pregnancy or breastfeeding, so talk with your doctor about your specific situation.
What are the side effects?
Vitamin E is generally well-tolerated. Serious side effects are rare but can include bleeding and, in some cases, hemorrhagic stroke at very high doses over a long time. High doses also increase bleeding risk, especially if you're already on blood thinners or have a vitamin K deficiency. Most people tolerate normal amounts without problems.
How much vitamin E is in one capsule?
The product facts don't specify the exact amount of vitamin E per capsule—just that the total product is 500 mg of cold-pressed evening primrose oil. You'll want to check the label or contact the manufacturer to confirm the vitamin E content, especially if you're concerned about dose-related bleeding risk.
Is this product safe to use long-term?
Usual dietary amounts of vitamin E are safe long-term, but high-dose long-term supplements may raise the risk of bleeding and other harms. If you're considering taking this for months or years, talk with your pharmacist about what dose is appropriate for your situation and health history.

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.

Evening Primrose Oil 500 mg Cold-Pressed label
Go deeper

The Full Monographs Behind Evening Primrose Oil 500 mg Cold-Pressed’s Ingredients

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

Herb & supplement monograph

Vitamin E

Interacts with 764 drugs

Vitamin E is an essential fat-soluble vitamin and antioxidant that most people get in adequate amounts from a normal diet. Supplements can help correct a true deficiency, but high-dose vitam...

Read the full Vitamin E monograph → Herb & supplement monograph

Evening Primrose

Interacts with 233 drugs

Evening primrose oil is a seed oil rich in gamma-linolenic acid (GLA), an omega-6 fatty acid, that is popularly used for skin conditions, PMS, and breast pain. The evidence behind most of th...

Read the full Evening Primrose monograph →
Sources

Sources & How We Checked

Evening Primrose Oil 500 mg Cold-Pressed'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 97 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.

Vitamin E 64 references
  1. Kim JM, White RH. Effect of vitamin E on the anticoagulant response to warfarin. Am J Cardiol 1996;77:545-6. PubMed
  2. Corrigan JJ Jr. The effect of vitamin E on warfarin-induced vitamin K deficiency. Ann N Y Acad Sci 1982;393:361-8. PubMed
  3. Corrigan JJ Jr. Coagulation problems relating to vitamin E. Am J Pediatr Hematol Oncol 1979;1:169-73.
  4. Corrigan JJ Jr, Marcus FI. Coagulopathy associated with vitamin E ingestion. JAMA 1974;230:1300-1. DOI
  5. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  6. Chang T, Benet LZ, Hebert MF. The effect of water-soluble vitamin E on cyclosporine pharmacokinetics in healthy volunteers. Clin Pharmacol Ther 1996;59:297-303. PubMed
  7. Pan SH, Lopez RR Jr, Sher LS, et al. Enhanced oral cyclosporine absorption with water-soluble vitamin E early after liver transplantation. Pharmacother 1996;16:59-65. DOI
  8. Anon. Dietary supplementation with n-3 polyunsaturated fatty acids and vitamin E after myocardial infarction: results of the GISSI-Prevenzione trial. Gruppo Italiano per lo Studio della Soprawivenza nell'Infarto miocardico. Lancet 1999;354:447-55. DOI
  9. Chappell LC, Seed PT, Briley AL, et al. Effect of antioxidants on the occurrence of pre-eclampsia in women at increased risk: a randomised trial. Lancet 1999;354:810-6. DOI
  10. Yusuf S, Dagenais G, Pogue J, et al. Vitamin E supplementation and cardiovascular events in high-risk patients. The heart outcomes prevention evaluation study investigators. N Engl J Med 2000;342:154-60. PubMed
  11. Stephens NG, Parsons A, Schofield PM, et al. Randomised controlled trial of vitamin E in patients with coronary disease: Cambridge Heart Antioxidant Study. Lancet 1996;347:781-6.
  12. The Alpha-Tocopherol, Beta Carotene Cancer Prevention Study Group. The effect of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers. N Engl J Med 1994;330:1029-35. PubMed
  13. Takahashi O. Haemorrhagic toxicity of a large dose of alpha-, beta-, gamma- and delta-tocopherols, ubiquinone, beta-carotene, retinol acetate and L-ascorbic acid in the rat. Food Chem Toxicol 1995;33:121-8.
  14. Briggs GB, Freeman RK, Yaffe SJ. Drugs in Pregnancy and Lactation. 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 1998.
  15. Sano M, Ernesto C, Thomas RG, et al. A controlled trial of selegiline, alpha-tocopherol, or both as treatment for Alzheimer's disease. The Alzheimer's Disease Cooperative Study. N Engl J Med 1997;336:1216-22. PubMed
  16. Liede KE, Haukka JK, Saxen LM, Heinonen OP. Increased tendency towards gingival bleeding caused by joint effect of alpha-tocopherol supplementation and acetylsalicylic acid. Ann Med 1998;30:542-6.
  17. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
  18. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  19. Liu M, Wallmon A, Olsson-Mortlock C, et al. Mixed tocopherols inhibit platelet aggregation in humans: potential mechanisms. Am J Clin Nutr 2003;77:700-6. PubMed
  20. Sokol RJ, Johnson KE, Karrer FM, et al. Improvement of cyclosporin absorption in children after liver transplantation by means of water-soluble vitamin E. Lancet 1991;338:212-4.. PubMed
  21. Stein JH, Carlsson CM, Papcke-Benson K, et al. The effects of lipid-lowering and antioxidant vitamin therapies on flow-mediated vasodilation of the brachial artery in older adults with hypercholesterolemia. J Am Coll Cardiol 2001;38:1806-13.. PubMed
  22. Carlsson CM, Papcke-Benson K, Carnes M, et al. Health-related quality of life and long-term therapy with pravastatin and tocopherol (vitamin E) in older adults. Drugs Aging 2002;19:793-805. . PubMed
  23. Cheung MC, Zhao XQ, Chait A, et al. Antioxidant supplements block the response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low HDL. Arterioscler Thromb Vasc Biol 2001;21:1320-6. PubMed
  24. Schrogie JJ. Coagulopathy and fat-soluble vitamins (letter). JAMA 1975;232:19. DOI
  25. Celestini A, Pulcinelli FM, Pignatelli P, et al. Vitamin E potentiates the antiplatelet activity of aspirin in collagen-stimulated platelets. Haematologica 2002;87:420-6.
  26. Stampfer MJ, Jakubowski JA, Faigel D, et al. Vitamin E supplementation effect on human platelet function, arachidonic acid metabolism, and plasma prostacyclin levels. Am J Clin Nutr 1988;47:700-6. PubMed
  27. Jandak J, Steiner M, Richardson PD. Alpha-tocopherol, an effective inhibitor of platelet adhesion. Blood 1989;73:141-9. DOI
  28. Freedman JE, Farhat JH, Loscalzo J, Keaney JF. Alpha-tocopherol inhibits aggregation of human platelets by a protein kinase C-dependent mechanism. Circulation 1996;94:2434-40. PubMed
  29. Steiner M. Vitamin E, a modifier of platelet function: rationale and use in cardiovascular and cerebrovascular disease. Nutr Rev 1999;57:306-9. PubMed
  30. Brodkin RH, Bleiberg J. Sensitivity to topically applied vitamin E. Arch Dermatol 1965;92:76-7. DOI
  31. Booth SL, Golly I, Sacheck JM, et al. Effect of vitamin E supplementation on vitamin K status in adults with normal coagulation status. Am J Clin Nutr 2004;80:143-8. 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.

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