Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

High Strength Evening Primrose Oil 500 mg Ingredients & Drug Interactions

by Simply Supplements

High Strength Evening Primrose Oil 500 mg label
See full label image
Capsule Category: Other Combinations
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 High Strength Evening Primrose Oil 500 mg 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

High Strength Evening Primrose Oil 500 mg is a dietary supplement by Simply Supplements 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 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 High Strength Evening Primrose Oil 500 mg by Simply Supplements

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

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.

HelloPharmacist Scorecard of High Strength Evening Primrose Oil 500 mg by Simply Supplements

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 Aug 6, 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 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains 2 active ingredients: vitamin E and evening primrose oil (500 mg per capsule). Vitamin E is a fat-soluble antioxidant your body needs for cell protection and immune function.

Evening primrose oil is a plant-based source of omega-6 fatty acids, including gamma-linolenic acid (GLA), which some people take for various health concerns. The capsule also contains gelatin, glycerin, and purified water as inactive ingredients.

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 and health support.
  • We looked for evidence on: Atopic dermatitis (eczema), Dysmenorrhea, Mastalgia, Menopausal symptoms, Diabetic neuropathy, PMS symptoms — and 3 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: Evening Primrose is rated "Likely Ineffective" for Mastalgia.

Vitamin E is effective for treating vitamin E deficiency and AVED (ataxia with vitamin E deficiency), a rare genetic condition. It's possibly effective for Alzheimer disease, beta-thalassemia, G6PD deficiency, and intracranial hemorrhage, though the evidence is not yet conclusive.

Evening primrose oil's evidence is weaker: it's possibly ineffective for asthma and likely ineffective for mastalgia (breast pain). For acne, ADHD, abortion, and hysteroscopy, there isn't enough reliable evidence to say whether it works.

The data we hold doesn't establish evening primrose oil as effective for any condition.

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 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.

Vitamin E from food and normal supplement doses is generally well tolerated. However, high-dose long-term supplements may raise your risk of bleeding and other serious side effects including hemorrhagic stroke and cardiovascular complications—particularly in male smokers.

High doses can also antagonize vitamin K-dependent clotting, increasing bleeding risk, especially if you have a vitamin K deficiency or take blood thinners. Evening primrose oil is generally well tolerated short-term, though quality evidence and long-term safety data are limited.

The most common side effects are gastrointestinal: abdominal pain, diarrhea, nausea, and vomiting. Rare reports include skin rash, acne, dizziness, headache, and seizures (though causality was unclear in the seizure case).

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?
  • 2 of the 2 matched ingredients can interact with medications — Vitamin E, Evening Primrose.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; cancer treatments; lithium.
  • For scale: 834 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 doctor or pharmacist if you're on anticoagulant or antiplatelet drugs (like warfarin, clopidogrel, or aspirin) or if you have a history of stroke—Moderate bleeding risk. Also check if you take CYP3A4 substrates, chemotherapy (alkylating agents or antitumor antibiotics), cyclosporine, selumetinib, lithium, phenothiazines, or HIV protease inhibitors like lopinavir/ritonavir.

Niacin users should know vitamin E may reduce its HDL-raising benefit.

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 may help if you have a documented vitamin E deficiency or AVED, but the evening primrose oil evidence for its labeled uses is weak or lacking. If you take blood thinners, any chemotherapy, lithium, an antipsychotic, or an HIV protease inhibitor, you need to check with your doctor or pharmacist before starting—the interaction risks are real.

Even without those medications, talk it over with your own healthcare provider if you're considering high-dose vitamin E long-term.

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

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 24, 2017.

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 High Strength Evening Primrose Oil 500 mg, straight from the product label.

Brand Simply Supplements
Barcode (UPC) 5060208410693
Net contents 180 Capsule(s)
Market status On market
Date entered into DSLD Feb 24, 2017
DSLD ID 71077
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other
Intended target group(s) Adult (18 - 50 Years)
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 High Strength Evening Primrose Oil 500 mg by Simply Supplements, 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:
1 Capsule(s)
Maximum serving Sizes:
6 Capsule(s)
UPC/BARCODE
5060208410693
IngredientAmount% DV
Vitamin E10 mg83.3%
Evening Primrose Oil500 mg--

Other ingredients: Gelatin, Glycerin, purified Water

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.
Precautions

Allergy Advice: Contains an ingredient derived from beef.

Food Supplement: This product should not be used as a substitute for a varied diet.

Important Information If you are taking any prescription medication, you have a medical condition or you have specific concerns about the suitability of our products, always consult your GP or Pharmacist prior to taking supplements.

Do not exceed stated dose.

Keep away from children at all times.

Do not use if seal is broken.

Pregnant or lactating women should consult a doctor before using this product.

General Statements

AutoDespatch Save 10% and get free P&P on all repeat orders by having your favourite supplements conveniently scheduled and delivered automatically with our unique AutoDespatch system. Same day despatch We will ensure your order is despatched on the day of receipt (when placed before 12.30pm) and that all orders placed after 12.30pm are despatched on the next working day. All sent 1st class!

PriceMatch guarantee! If you buy from us and then see the same product cheaper elsewhere we will refund the difference plus 10%!

NRV=Nutrient Reference Value

Image is for illustration purposes only.

General

S151

Suggested/Recommended/Usage/Directions

Suggested Daily Intake Take one to six capsules daily as a food supplement or as directed by a healthcare professional.

Seals/Symbols

Quality Assured

Formula

Product Information Evening Primrose Oil contains substantial amounts of essential fatty acids (EFAs) which have been found to offer various beneficial health-related properties within the body.

High Strength Evening Primrose Oil 500 mg A rich source of GLA

Storage

Store in a cool dry place.

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

See for yourself

High Strength Evening Primrose Oil 500 mg by Simply Supplements label

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

High Strength Evening Primrose Oil 500 mg 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 High Strength Evening Primrose Oil 500 mg by Simply Supplements

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

Serving size1 Capsule(s) Dosage formCapsule 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
10 mg per serving Form: DL-Alpha-Tocopheryl

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 Oil

Interacts with
233 drugs
500 mg per serving Form: Gamma-Linolenic Acid

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 Oil monograph & interactions

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

Interaction report

High Strength Evening Primrose Oil 500 mg by Simply Supplements Drug Interactions

Want to check YOUR meds against High Strength Evening Primrose Oil 500 mg?

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 Oil 233

Individual Drug Interactions

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

2 of the 2 ingredients in High Strength Evening Primrose Oil 500 mg interact with drugs. Each result below shows which ingredient is responsible. Vitamin E Evening Primrose Oil

Each ingredient & the kinds of drugs it affects

For each ingredient in High Strength Evening Primrose Oil 500 mg 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 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 Oil full monograph & interactions
The maker

Brand information

Manufacturer and brand details for High Strength Evening Primrose Oil 500 mg, from the product label.

Simply Supplements

See all Simply Supplements products
Name
Simply Supplements
Street Address
PO Box 204
City
Guernsey
ZipCode
GY1 5SS
Phone Number
0800 988 0292
Web Address
www.simplysupplements.co.uk
Pharmacist Counseling Corner

High Strength Evening Primrose Oil 500 mg by Simply Supplements: Common Questions

Does High Strength Evening Primrose Oil 500 mg by Simply Supplements interact with any medications?
Yes. Based on its ingredients, High Strength Evening Primrose Oil 500 mg 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?
High Strength Evening Primrose Oil 500 mg 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.
Is this safe to take while I'm pregnant?
Vitamin E and evening primrose oil are both rated possibly safe in pregnancy based on the data we hold. However, the facts note to avoid high-dose vitamin E supplements unless your doctor directs otherwise, and evening primrose oil has unclear evidence with some safety concerns—so pregnancy makes both worth discussing with your doctor before starting.
What are the most common side effects?
Evening primrose oil is most likely to cause gastrointestinal upset: abdominal pain, diarrhea, nausea, and vomiting. Vitamin E at normal dietary doses is well tolerated, but high-dose supplements carry a risk of bleeding.
Can I take this while breastfeeding?
Vitamin E is likely safe while breastfeeding in normal dietary amounts, though high-dose supplements need your doctor's guidance. Evening primrose oil is possibly safe, but there isn't enough reliable safety data to be certain—talk it over with your doctor or pharmacist.
Will this actually help my (specific condition)?
Vitamin E works for vitamin E deficiency and AVED, a rare genetic disorder. For Alzheimer disease, beta-thalassemia, and some other conditions, there's possibly some benefit, but evidence is incomplete. Evening primrose oil's evidence is weak—it's likely ineffective for breast pain and possibly ineffective for asthma. For most other uses listed, there simply isn't enough data.
Why does this product have so many drug interactions?
The 834 interactions come from vitamin E's roles in blood clotting and how your liver processes many medications, plus evening primrose oil's effects on platelet function and metabolism. Two active ingredients can each interact with hundreds of different drugs.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if High Strength Evening Primrose Oil 500 mg is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.

High Strength Evening Primrose Oil 500 mg label
Go deeper

The Full Monographs Behind High Strength Evening Primrose Oil 500 mg’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

High Strength Evening Primrose Oil 500 mg'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
  32. Miller ER 3rd, Pastor-Barriuso R, Dalal D, et al. Meta-analysis: High-dosage vitamin E supplementation may increase all-cause mortality. Ann Intern Med 2005;142:60520-53. PubMed
  33. Lonn E, Bosch J, Yusuf S, et al. HOPE and HOPE-TOO Trial Investigators. Effects of long-term vitamin E supplementation on cardiovascular events and cancer: a randomized controlled trial. JAMA 2005;293:1338-47. PubMed
  34. Landes N, Pfluger P, Kluth D, et al. Vitamin E activates gene expression via the pregnane X receptor. Biochem Pharmacol 2003;65:269-73. . PubMed
  35. Brigelius-Flohe R. Vitamin E and drug metabolism. Biochem Biophys Res Commun 2003;305:737-40. PubMed
  36. Prasad KN. Rationale for using high-dose multiple dietary antioxidants as an adjunct to radiation therapy and chemotherapy. J Nutr 2004;134:3182S-3S. PubMed
  37. Conklin KA. Cancer chemotherapy and antioxidants. J Nutr 2004;134:3201S-3204S. PubMed
  38. Schurks M, Glynn RJ, Rist PM, et al. Effects of vitamin E on stroke subtypes: meta-analysis of randomized controlled trials. BMJ 2010;341: c5702. doi: 10.1136/bmj.c5702.
  39. Lawson KA, Wright ME, Subar A, et al. Multivitamin use and risk of prostate cancer in the National Institutes of Health-AARP Diet and Health Study. J Natl Cancer Inst 2007;99:754-64. PubMed
  40. Gaziano JM, Glynn RJ, Christen WG, et al. Vitamins E and C in the prevention of prostate total cancer in men: the physicians' health study II randomised controlled trial. JAMA 2009;301:52-62.
  41. Hayden KM, Welsh-Bohmer KA, Wengreen HJ, et al; Cache County Investigators. Risk of mortality with vitamin E supplements: the Cache County study. Am L Med 2007;120:180-4. PubMed
  42. Smedts HP, de Vries JH, Rakhshandehroo M, et al. High maternal vitamin E intake by diet or supplements is associated with congenital heart defects in the offspring. BJOG 2009;116:416-23. PubMed
  43. Klein EA, Thompson IM Jr, Tangen CM, et al. Vitamin E and the risk of prostate cancer: the Selenium and Vitamin E Cancer Prevention Trial (SELECT). JAMA 2011;306:1549-56. PubMed
  44. Huang, H. Y., Caballero, B., Chang, S., Alberg, A. J., Semba, R. D., Schneyer, C. R., Wilson, R. F., Cheng, T. Y., Vassy, J., Prokopowicz, G., Barnes, G. J., and Bass, E. B. The efficacy and safety of multivitamin and mineral supplement use to prevent ca
  45. Sesso, H. D., Buring, J. E., Christen, W. G., Kurth, T., Belanger, C., MacFadyen, J., Bubes, V., Manson, J. E., Glynn, R. J., and Gaziano, J. M. Vitamins E and C in the prevention of cardiovascular disease in men: the Physicians' Health Study II randomiz
  46. Papaioannou, D., Cooper, K. L., Carroll, C., Hind, D., Squires, H., Tappenden, P., and Logan, R. F. Antioxidants in the chemoprevention of colorectal cancer and colorectal adenomas in the general population: a systematic review and meta-analysis. Colorec PubMed
  47. Cooper, K., Squires, H., Carroll, C., Papaioannou, D., Booth, A., Logan, R. F., Maguire, C., Hind, D., and Tappenden, P. Chemoprevention of colorectal cancer: systematic review and economic evaluation. Health Technol.Assess. 2010;14(32):1-206. PubMed
  48. Mathew, M. C., Ervin, A. M., Tao, J., and Davis, R. M. Antioxidant vitamin supplementation for preventing and slowing the progression of age-related cataract. Cochrane.Database.Syst.Rev. 2012;6:CD004567. PubMed
  49. Rahimi, R., Nikfar, S., Rezaie, A., and Abdollahi, M. A meta-analysis on the efficacy and safety of combined vitamin C and E supplementation in preeclamptic women. Hypertens.Pregnancy. 2009;28(4):417-434. PubMed
  50. Soares, K. V. and McGrath, J. J. Vitamin E for neuroleptic-induced tardive dyskinesia. Cochrane.Database.Syst.Rev. 2001;(4):CD000209. DOI
  51. Roed-Petersen, J. and Hjorth, N. Contact dermatitis from antioxidants. Br.J.Dermatol. 1976;94(3):233-241. PubMed
  52. Brion, L. P., Bell, E. F., Raghuveer, T. S., and Soghier, L. What is the appropriate intravenous dose of vitamin E for very-low-birth-weight infants? J.Perinatol. 2004;24(4):205-207. PubMed
  53. Manny, T., Pettus, J., Hemal, A., Marks, M., and Mirzazadeh, M. Penile sclerosing lipogranulomas and disfigurement from use of "1Super Extenze" among Laotian immigrants. J.Sex Med. 2011;8(12):3505-3510. PubMed
  54. Musso, G., Cassader, M., Rosina, F., and Gambino, R. Impact of current treatments on liver disease, glucose metabolism and cardiovascular risk in non-alcoholic fatty liver disease (NAFLD): a systematic review and meta-analysis of randomised trials. Diabe PubMed
  55. Bell, E. F. Upper limit of vitamin E in infant formulas. J.Nutr. 1989;119(12 Suppl):1829-1831. PubMed
  56. Manzano, D., Aguirre, A., Gardeazabal, J., Eizaguirre, X., and Diaz Perez, J. L. Allergic contact dermatitis from tocopheryl acetate (vitamin E) and retinol palmitate (vitamin A) in a moisturizing cream. Contact Dermatitis 1994;31(5):324.
  57. Barak, Y., Swartz, M., Shamir, E., Stein, D., and Weizman, A. Vitamin E (alpha-tocopherol) in the treatment of tardive dyskinesia: a statistical meta-analysis. Ann.Clin.Psychiatry 1998;10(3):101-105.
  58. Chae CU, Albert CM, Moorthy MV, et al. Vitamin E supplementation and the risk of heart failure in women. Circ Heart Fail. 2012;5(2):176-82. PubMed
  59. Rumbold A, Ota E, Hori H, Miyazaki C, Crowther CA. Vitamin E supplementation in pregnancy. Cochrane Database Syst Rev. 2015;(9):CD004069. PubMed
  60. Prescribing information: KOSELUGO (selumetinib) capsules. U.S. Food and Drug Administration. Available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2020/213756s000lbl.pdf.
  61. Warshaw EM, Ruggiero JL, DeKoven JG, et al. Patch testing with tocopherol and tocopherol acetate: the North American Contact Dermatitis Group experience, 2001 to 2016. Dermatitis. 2021;32(5):308-18. PubMed
  62. US Preventive Services Task Force, Mangione CM, Barry MJ, et al. Vitamin, Mineral, and Multivitamin Supplementation to Prevent Cardiovascular Disease and Cancer: US Preventive Services Task Force Recommendation Statement. JAMA 2022;327(23):2326-2333. PubMed
  63. Abrol R, Kaushik R, Goel D, Sama S, Kaushik RM, Kala M. Vitamin E-induced coagulopathy in a young patient: a case report. J Med Case Rep 2023;17(1):107. PubMed
  64. Abtahi-Naeini B, Rastegarnasab F, Saffaei A. Liquid vitamin E injection for cosmetic facial rejuvenation: A disaster report of lipogranuloma. J Cosmet Dermatol 2022;21(11):5549-5554. PubMed

See these in context on the Vitamin E monograph →

Evening Primrose 33 references
  1. Shaw D, Leon C, Kolev S, Murray V. Traditional remedies and food supplements: a 5-year toxicological study (1991-1995). Drug Saf 1997;17:342-56.
  2. Laivuori H, Hovatta O, Viinikka L, et al. Dietary supplementation with primrose oil or fish oil does not change urinary excretion of prostacyclin and thromboxane metabolites in pre-eclamptic women. Prostaglandins Leukot Essent Fatty Acids 1993;49:691-4. PubMed
  3. Dove D, Johnson P. Oral evening primrose oil: its effect on length of pregnancy and selected intrapartum outcomes in low-risk nulliparous women (abstract). J Nurse Midwifery 1999;44:320-4. PubMed
  4. Guivernau M, Meza N, Barja P, Roman O. Clinical and experimental study on the long-term effect of dietary gamma-linolenic acid on plasma lipids, platelet aggregation, thromboxane formation, and prostacyclin production. Prostaglandins Leukot Essent Fatty A PubMed
  5. Cant A, Shay J, Horrobin DF. The effect of maternal supplementation with linoleic and gamma- linolenic acids on the fat composition and content of human milk: a placebo-controlled trial. J Nutr Sci Vitaminol (Tokyo) 1991;37:573-9. PubMed
  6. Keen H, Payan J, Allawi J, et al. Treatment of diabetic neuropathy with gamma-linolenic acid. The gamma-Linolenic Acid Multicenter Trial Group. Diabetes Care 1993;16:8-15.
  7. Blommers J, de Lange-De Klerk ES, Kuik DJ, et al. Evening primrose oil and fish oil for severe chronic mastalgia: a randomized, double-blind, controlled trial. Am J Obstet Gynecol 2002;187:1389-94.. DOI
  8. Cheung KL. Management of cyclical mastalgia in oriental women: pioneer experience of using gamolenic acid (Efamast) in Asia. Aust N Z J Surg 1999;69:492-4..
  9. Das UN. The lipids that matter from infant nutrition to insulin resistance. Prostaglandins Leukot Essent Fatty Acids 2002;67:1-12. PubMed
  10. Wedig KE, Whitsett JA. Down the primrose path: petechiae in a neonate exposed to herbal remedy for parturition. J Pediatr 2008;152:140, 140.e1. PubMed
  11. Ty-Torredes KA. The effect of oral evening primrose oil on bishop score and cervical length amongst term gravidas. Am J Obstet Gynecol. 2006;195(6 Suppl 1):S30.
  12. Moodley J and Norman RJ. Attempts at dietary alteration of prostaglandin pathways in the management of pre-eclampsia. Prostaglandins Leukot Essent Fatty Acids 1989;37(3):145-147. PubMed
  13. Tong M. [Treatment of hyperlipemia with evening primrose oil capsules]. Zhong Xi Yi Jie He Za Zhi. 1988;8:469-71, 452-3.
  14. Holman CP and Bell AF. A trial of evening primrose oil in the treatment of chronic schizophrenia. J Orhtomolecular Psych 1983;12:302-304.
  15. Vaddadi KS. The use of gamma-linolenic acid and linoleic acid to differentiate between temporal lobe epilepsy and schizophrenia. Prostaglandins Med 1981;6(4):375-379. PubMed
  16. Zou L, Harkey MR, and Henderson GL. Effects of herbal components on cDNA-expressed cytochrome P450 enzyme catalytic activity. Life Sci 8-16-2002;71(13):1579-1589. PubMed
  17. Yoon, S., Lee, J., and Lee, S. The therapeutic effect of evening primrose oil in atopic dermatitis patients with dry scaly skin lesions is associated with the normalization of serum gamma-interferon levels. Skin Pharmacol Appl.Skin Physiol 2002;15(1):20- PubMed
  18. Bamford, J. T., Gibson, R. W., and Renier, C. M. Atopic eczema unresponsive to evening primrose oil (linoleic and gamma- linolenic acids). J Am.Acad.Dermatol. 1985;13(6):959-965.
  19. Preece PE, Hanslip JI Gilbert L. Evening primrose oil (Efamol) for mastalgia. In: Horrobin DF. Clinical Uses of Essential Fatty Acids . Montreal, Quebec: Eden;1982.
  20. Parveen, S. Sarwar G. Ali M. Channa G. A. Danazol versus oil of evening primrose in the treatment of mastalgia. Pakistan Journal of Surgery. 2007;23(1):10-13.
  21. Belch JJF, Shaw B, O'Dowd A, et al. Evening primrose oil (Efamol) as a treatment for cold-induced vasospasm (Raynaud's phenomenon). Prog Lipid Res 1986;25:335-40.
  22. Johnson, M., Ostlund, S., Fransson, G., Kadesjo, B., and Gillberg, C. Omega-3/omega-6 fatty acids for attention deficit hyperactivity disorder: a randomized placebo-controlled trial in children and adolescents. J.Atten.Disord. 2009;12(5):394-401. PubMed
  23. Farzaneh F, Fatehi S, Sohrabi MR, Alizadeh K. The effect of oral evening primrose oil on menopausal hot flashes: a randomized clinical trial. Arch Gynecol Obstet 2013;288(5):1075-9. PubMed
  24. Puri BK. The safety of evening primrose oil in epilepsy. Prostaglandins Leukotrienes Essential Fatty Acids 2007;77:101-3. PubMed
  25. Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. PubMed
  26. Osman M, Badawi E. Evening primrose oil reducing serum lithium concentration. Ther Adv Psychopharmacol. 2016 Oct;6(5):343-44. PubMed
  27. Kalati M, Kashanian M, Jahdi F, Naseri M, Haghani H, SHeikhansari N. Evening primrose oil and labour, is it effective? A randomized clinical trial. J Obstet Gynaecol. 2018 Feb 9:1-5.
  28. Sharif SN, Darsareh F. Impact of evening primrose oil consumption on psychological symptoms of postmenopausal women: a randomized double-blinded placebo-controlled clinical trial. Menopause. 2020;27(2):194-198. PubMed
  29. Shahraki AD, Mirhoseini S, Movahedi M, Hajihashemy M, Haghollahi F. Comparative Study of the Effect of Vaginal use of Primrose Oil with Misoprostol on Cervical Preparation of Prim Gravid Women: A Double-blind Clinical Trial. Adv Biomed Res 2023;12:78. PubMed
  30. Shahinfar S, Abedi P, Jahanfar S, Khajehpoor M, Chashmyazdan M. The effect of evening primrose oil on cervical ripening and birth outcomes: A systematic review and meta-analysis. Heliyon 2023;9(2):e13414. PubMed
  31. Mahmoodinasab M, Loripoor M, Vazirinejad R, Aminzadeh F. Effect of misoprostol with and without evening primrose (Oenothera biennis) on induction of missed abortion. Avicenna J Phytomed 2023;13(5):454-462.
  32. Hashemi H, Hasanpoor-Azghady SB, Farahani M, Amiri-Farahani L. Comparison of the effect of vaginal misoprostol and evening primrose oil capsule with misoprostol alone on the consequences of abortion in women with intrauterine fetal death: a randomized cli
  33. Ariana S, Amjadi N, Kazemi SN, Ahmadli Z. The Use of Evening Primrose Oil for Cervical Ripening in Low-Risk Women with Term Pregnancy: A Randomized Double-Blinded Controlled Trial. Complement Med Res 2024;31(3):215-221. PubMed

See these in context on the Evening Primrose monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

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

Keep exploring
Supplement interaction checker › Check any supplement or product against your medications Drug–drug interactions › Check two or more of your medications against each other Browse medications A–Z › Every drug we've checked against herbs & supplements NDC & pricing lookup › Find a drug’s NDCs, packaging and costs Ask a pharmacist › Free, personal answer from our licensed team