Interactions on record — worth a quick check against your medications. Based on 2 of 5 ingredients. Check your meds →
Dietary supplement

Evening Primrose Oil 500 mg Ingredients & Drug Interactions

by Vitabase

Evening Primrose Oil 500 mg label
See full label image
Softgel Capsule Category: Fat/fatty Acid
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking 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

Evening Primrose Oil 500 mg is a dietary supplement by Vitabase with 5 active ingredients. Its ingredients are commonly taken for heart health, healthy cooking fat, skin moisturizing.Based on those ingredients, 308 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Evening Primrose seed Oil, Oleic Acid. 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 by Vitabase

Ask about any prescription or over-the-counter medication and we check it for interactions with Evening Primrose Oil 500 mg by Vitabase — 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 by Vitabase

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 30, 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 5 of its 5 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Vitabase Evening Primrose Oil contains 5 active ingredients: gamma-linolenic acid, oleic acid, palmitic acid, linoleic acid, and evening primrose seed oil. These are fatty acids naturally present in evening primrose seeds.

The product is delivered in softgel capsules made with gelatin, glycerin, and water as inactive ingredients.

Does it work?

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

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: Support for skin health and hormonal balance.
  • We looked for evidence on: Atopic dermatitis (eczema), Mastalgia, Menopausal symptoms, Premenstrual syndrome (PMS), Dry skin, Hormonal support — and 2 related terms.
  • The closest evidence on file: Evening Primrose is rated "Likely Ineffective" for Mastalgia (Natural Medicines).
  • Also on file: Evening Primrose is rated "Insufficient Reliable Evidence To Rate" for Atopic dermatitis (eczema), Dry skin, Menopausal symptoms, Premenstrual syndrome (PMS).

The evidence for evening primrose oil is mixed. For asthma, the data suggests it's likely ineffective.

For breast pain (mastalgia), it's rated likely ineffective. Several other uses—including ADHD, acne, and hysteroscopy procedures—have insufficient evidence to establish whether it works.

The oleic acid in the product is rated possibly effective for high cholesterol and coronary heart disease, though that comes from research on oleic acid from olive oil in the diet, not from this supplement form.

The evidence, ingredient by ingredient Oleic Acid 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 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.

Evening primrose oil is generally well tolerated in the short term, though quality evidence and long-term safety data are limited. Most common side effects from oral use are abdominal pain, bloating, diarrhea, indigestion, gas, nausea, and vomiting.

Some people report skin rash, acne, dizziness, or headache. There is a case report of seizures in someone taking evening primrose oil during anesthesia, but other drugs were also involved, so the cause wasn't clear.

For pregnancy, evening primrose oil is rated possibly safe, and the same applies to breastfeeding. However, the facts note that concentrated supplement doses lack good safety data in pregnancy, so concentrated forms are best avoided unless your doctor directs otherwise.

Safety data for breastfeeding is also limited, and medical advice is advised.

Side effects, ingredient by ingredient Oleic Acid 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 — Evening Primrose, Oleic Acid.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; lithium.
  • For scale: 308 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, have your doctor or pharmacist double-check if you use blood thinners or antiplatelet drugs (Moderate risk of bleeding), lithium (Moderate risk of lowered levels), antipsychotics like phenothiazines (Moderate risk of seizures), HIV medications like lopinavir/ritonavir (Moderate risk of increased drug levels), diabetes drugs (Moderate risk of stronger effects), or any CYP2C9 substrates (Minor risk of increased levels). Use the medication checker below to see your exact drugs.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

Evening Primrose Oil 500 mg by Vitabase may help with high cholesterol or heart disease (through its oleic acid), though the evidence is preliminary. It's not effective for asthma and likely won't help breast pain.

The real concern is medication interactions—especially with blood thinners, lithium, antipsychotics, HIV drugs, and diabetes medications. If you take any prescription drugs, check them against this product's interactions before you start, and talk it over with your own doctor or pharmacist.

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

Assessment coverage: 2 of 5 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 23, 2012.

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, straight from the product label.

Brand Vitabase
Net contents 90 Softgel(s)
Market status On market
Date entered into DSLD Mar 23, 2012
DSLD ID 6867
Product type Fat/fatty Acid
Supplement form Softgel Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
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 Evening Primrose Oil 500 mg by Vitabase, 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 Softgel(s)
Maximum serving Sizes:
1 Softgel(s)
IngredientAmount% DV
Gamma-Linolenic Acid45 mg--
Oleic Acid35 mg--
Palmitic Acid30 mg--
Linoleic Acid350 mg--
Evening Primrose seed Oil500 mg--

Other ingredients: Gelatin, Glycerin, 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.
Formulation

Contains No Added sugar, salt, dairy, yeast, wheat, corn, soy, preservatives, artificial colors or flavors.

Our Evening Primrose Oil is Hexane Free.

Suggested/Recommended/Usage/Directions

Suggested Use: As a dietary supplement, adults take one (1) softgel capsule, three (3) times daily with meals, or as directed by a health professional.

Storage

Store in a cool, dry place and away from direct light.

Precautions

Keep out of reach of children.

General Statements

QUALITY AND POTENCY GUARANTEED.

Vitabase uses only high quality ingredients.

FDA Disclaimer Statement

These statements have not been evaluated by the FDA. Product is not intended to diagnose, treat, cure, or prevent any diseases.

Seals/Symbols

Vb

Formula

High Source of Gamma-Linolenic Acid (GLA)

It is 100% pure cold pressed Evening Primrose Oil, derived from the seeds of the Evening Primrose plant. It is a high source of Gamma-Linolenic Acid.

FDA Statement of Identity

DIETARY SUPPLEMENT

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 by Vitabase label

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

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 Evening Primrose Oil 500 mg by Vitabase

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 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.

Gamma-Linolenic Acid

45 mg per serving

Oleic Acid

Interacts with
86 drugs
35 mg per serving

Oleic acid is a heart-healthy monounsaturated fat found mainly in olive oil, canola oil, avocados, and nuts. As part of a Mediterranean-style diet, it...

Oleic Acid monograph & interactions

Palmitic Acid

30 mg per serving

Linoleic Acid

350 mg per serving

Evening Primrose 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 seed Oil monograph & interactions

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

Interaction report

Evening Primrose Oil 500 mg by Vitabase Drug Interactions

Want to check YOUR meds against 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
308Drugs
234 Moderate 74 Minor

Ingredients driving the most interactions

Evening Primrose seed Oil 233
Oleic Acid 86

Individual Drug Interactions

The ingredients in Evening Primrose Oil 500 mg interact with 308 drugs. Click any drug to see the details.

2 of the 5 ingredients in Evening Primrose Oil 500 mg interact with drugs. Each result below shows which ingredient is responsible. Evening Primrose seed Oil Oleic Acid

Each ingredient & the kinds of drugs it affects

For each ingredient in 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.

Evening Primrose 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 seed Oil full monograph & interactions

Oleic Acid1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, oleic acid might increase the effects of antidiabetes drugs. Preliminary clinical research in patients with type 2 diabetes taking oral hypoglycemic drugs shows that eating a diet rich in oleic acid from olive oil decreases fasting blood glucose levels when compared to eating a diet rich in linoleic acid from sunflower oil. It is unknown if taking oleic acid supplements would have this effect or if this change is clinically significant. Until more is known, use caution. Dose adjustment may be necessary. Some antidiabetes drugs include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, metformin (Glucophage), pioglitazone (Actos), rosiglitazone (Avandia), and others.

Likelihood Possible Evidence B
Oleic Acid full monograph & interactions
The maker

Brand information

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

Vitabase

See all Vitabase products
Name
Vitabase.com
City
Monroe
State
GA
ZipCode
30656
Pharmacist Counseling Corner

Evening Primrose Oil 500 mg by Vitabase: Common Questions

Does Evening Primrose Oil 500 mg by Vitabase interact with any medications?
Yes. Based on its ingredients, Evening Primrose Oil 500 mg has a known interaction with 308 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 contains 5 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 evening primrose oil help my arthritis or rheumatoid arthritis?
The product facts don't include any evidence rating for arthritis or rheumatoid arthritis, so we can't say from the data we hold whether it works for that. Your doctor or pharmacist can point you to the latest research or suggest other options.
What's the most common side effect if I take this?
Digestive upset is most common—abdominal pain, bloating, diarrhea, indigestion, gas, nausea, or vomiting. A smaller number of people report skin rash, acne, dizziness, or headache.
Can I take evening primrose oil if I'm pregnant?
It's rated possibly safe in pregnancy, but supplement-level doses haven't been well studied. The facts advise that concentrated forms are best avoided unless your doctor directs you to use one, so talk with your doctor before starting it.
Is it safe to breastfeed while taking this?
Evening primrose oil is rated possibly safe during breastfeeding, but long-term safety data are limited. Since the facts note that caution and medical advice are advised, check with your doctor or pharmacist before using it while nursing.
What's oleic acid and why is it in this product?
Oleic acid is a natural fatty acid found in evening primrose seeds. It's rated possibly effective for high cholesterol and heart disease, which is why it's part of this product's profile.

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

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

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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 label
Go deeper

The Full Monographs Behind 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

Oleic Acid

Interacts with 86 drugs

Oleic acid is a heart-healthy monounsaturated fat found mainly in olive oil, canola oil, avocados, and nuts. As part of a Mediterranean-style diet, it is widely viewed as a healthier replace...

Read the full Oleic Acid 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'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 52 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.

Oleic Acid 19 references
  1. Madigan C, Ryan M, Owens D, et al. Dietary unsaturated fatty acids in type 2 diabetes: higher levels of postprandial lipoprotein on a linoleic acid-rich sunflower oil diet compared with an oleic acid-rich olive oil diet. Diabetes Care 2000;23:1472-7. PubMed
  2. Gillingham, L. G., Gustafson, J. A., Han, S. Y., Jassal, D. S., and Jones, P. J. High-oleic rapeseed (canola) and flaxseed oils modulate serum lipids and inflammatory biomarkers in hypercholesterolaemic subjects. Br J Nutr 2011;105(3):417-427. PubMed
  3. Jones PJ, Senanayake VK, Pu S, Jenkins DJ, Connelly PW, Lamarche B, Couture P, Charest A, Baril-Gravel L, West SG, Liu X, Fleming JA, McCrea CE, Kris-Etherton PM. DHA-enriched high-oleic acid canola oil improves lipid profile and lowers predicted cardiova
  4. Cater, N. B., Heller, H. J., and Denke, M. A. Comparison of the effects of medium-chain triacylglycerols, palm oil, and high oleic acid sunflower oil on plasma triacylglycerol fatty acids and lipid and lipoprotein concentrations in humans. Am.J Clin.Nutr PubMed
  5. Mozaffarian D, Clarke R. Quantitative effects on cardiovascular risk factors and coronary heart disease risk of replacing partially hydrogenated vegetable oils with other fats and oils. Eur J Clin Nutr. 2009;63(Suppl 2):S22-33. PubMed
  6. Cao Y, Hou L, Wang W. Dietary total fat and fatty acids intake, serum fatty acids and risk of breast cancer: A meta-analysis of prospective cohort studies. Int J Cancer. 2016;138(8):1894-904. doi: 10.1002/ijc.29938. PubMed
  7. FDA completes review of qualified health claim petition for oleic acid and the risk of coronary heart disease. November 2018. Available at: www.fda.gov/Food/NewsEvents/ConstituentUpdates/ucm624758.htm. Accessed January 25, 2019.
  8. Liu X, Kris-Etherton PM, West SG, et al. Effects of canola and high-oleic-acid canola oils on abdominal fat mass in individuals with central obesity. Obesity. 2016;24(11):2261-2268. PubMed
  9. Bowen KJ, Kris-Etherton PM, West SG, et al. Diets enriched with conventional or high-oleic acid canola oils lower atherogenic lipids and lipoproteins compared to a diet with a western fatty acid profile in adults with central adiposity. J Nutr. 2019;149(3 PubMed
  10. Steffen BT, Duprez D, Szklo M, Guan W, Tsai MY. Circulating oleic acid levels are related to greater risks of cardiovascular events and all-cause mortality: The Multi-Ethnic Study of Atherosclerosis. J Clin Lipidol. 2018;12(6):1404-1412. PubMed
  11. Banim PJ, Luben R, Khaw KT, Hart AR. Dietary oleic acid is inversely associated with pancreatic cancer - Data from food diaries in a cohort study. Pancreatology. 2018;18(6):655-660. PubMed
  12. Morin SJ, Gaziano JM, Djoussé L. Relation between plasma phospholipid oleic acid and risk of heart failure. Eur J Nutr. 2018;57(8):2937-2942. PubMed
  13. Samieri C, Féart C, Proust-Lima C, et al. Olive oil consumption, plasma oleic acid, and stroke incidence: the Three-City Study. Neurology. 2011;77(5):418-25. PubMed
  14. Compher CW, Kinosian BP, Rubesin SE, Ratcliffe SJ, Metz DC. Energy absorption is reduced with oleic acid supplements in human short bowel syndrome. JPEN J Parenter Enteral Nutr. 2009;33(1):102-8. PubMed
  15. Ben Fradj MK, Ouanes Y, Hadj-Taieb S, et al. Decreased oleic acid and marine n?-?3 polyunsaturated fatty acids in Tunisian patients with urothelial bladder cancer. Nutr Cancer. 2018;70(7):1043-1050.
  16. de Silva PS, Luben R, Shrestha SS, Khaw KT, Hart AR. Dietary arachidonic and oleic acid intake in ulcerative colitis etiology: a prospective cohort study using 7-day food diaries. Eur J Gastroenterol Hepatol. 2014;26(1):11-8. PubMed
  17. Higashi K, Shige H, Ito T, et al. Effect of a low-fat diet enriched with oleic acid on postprandial lipemia in patients with type 2 diabetes mellitus. Lipids. 2001;36(1):1-6. PubMed
  18. Lin HC, van Citters GW, Heimer F, Bonorris G. Slowing of gastrointestinal transit by oleic acid: a preliminary report of a novel, nutrient-based treatment in humans. Dig Dis Sci. 2001;46(2):223-9. PubMed
  19. Li D, Tong Y, Li Y. Associations between dietary oleic acid and linoleic acid and depressive symptoms in perimenopausal women: The Study of Women's Health Across the Nation. Nutrition. 2020 Mar;71:110602. PubMed

See these in context on the Oleic Acid 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
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  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 →

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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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