Interactions on record — worth a quick check against your medications. Based on 2 of 4 ingredients. Check your meds →
Dietary supplement

OmegaFactors Ultra Prim Ingredients & Drug Interactions

by Natural Factors

OmegaFactors Ultra Prim label
See full label image
Softgel Capsule Category: Fat/fatty Acid
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 OmegaFactors Ultra Prim 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

OmegaFactors Ultra Prim is a dietary supplement by Natural Factors with 4 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 Oil, Oleic Acid. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against OmegaFactors Ultra Prim by Natural Factors

Ask about any prescription or over-the-counter medication and we check it for interactions with OmegaFactors Ultra Prim by Natural Factors — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of OmegaFactors Ultra Prim by Natural Factors

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 27, 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 4 of its 4 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

OmegaFactors Ultra Prim contains four active ingredients — three fatty acids and an herbal oil. Gamma-linolenic acid, linoleic acid, and oleic acid are fatty compounds that play a role in how your body processes fats and inflammation.

Evening primrose oil, made from the seeds of the evening primrose plant, is a source of gamma-linolenic acid and linoleic acid. The product comes in a softgel capsule, which is the inactive carrier.

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: evening primrose oil for skin and hormonal health.
  • We looked for evidence on: Atopic dermatitis (eczema), Mastalgia, Menopausal symptoms, Premenstrual syndrome (PMS), Dry skin, skin inflammation — and 1 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 here is mixed and limited. Oleic acid is rated possibly effective for high cholesterol and heart disease — the research is preliminary, but it points in a promising direction.

Evening primrose oil, however, shows mostly weak evidence: it's rated likely ineffective for mastalgia (breast pain) and possibly ineffective for asthma. For other uses the facts cover — including ADHD, acne, and a few others — there isn't enough reliable evidence to rate it either way.

If you're considering this supplement for a specific reason, talk with your doctor about whether the evidence supports its use for your situation.

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 long-term safety data are sparse. The most common side effects from oral use are gastrointestinal — abdominal pain, diarrhea, bloating, nausea, and vomiting — plus occasional reports of rash, acne, dizziness, and headache.

Oleic acid in the amounts eaten from foods is safe, but concentrated supplement doses haven't been well studied. For pregnancy, the safety data advise caution.

Evening primrose oil is rated possibly safe during pregnancy and lactation, but the evidence is unclear — some reports raise concerns. Oleic acid from food is considered safe, but supplement-level doses lack good safety data.

If you're pregnant or breastfeeding, talk with your doctor or pharmacist before starting this product.

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, double-check with your doctor or pharmacist if you take blood thinners or antiplatelet drugs like warfarin or aspirin (Moderate risk of bleeding), lithium (Moderate risk of dropped levels), phenothiazines or other antipsychotics (Moderate risk of seizures), the HIV drug lopinavir/ritonavir (Moderate risk of higher drug levels), blood sugar medications (Moderate risk of lower glucose), or any drug broken down by the CYP2C9 liver enzyme (Minor risk of higher drug levels).

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.

OmegaFactors Ultra Prim is a fatty-acid supplement with limited evidence behind it and several important medication interactions to watch for, especially with blood thinners, lithium, antipsychotics, and HIV medications. If you take any prescription drugs, check them against the tool on this page and confirm with your doctor or pharmacist before adding this supplement.

It's generally well tolerated short-term, but long-term safety is less clear.

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

Assessment coverage: 2 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 26, 2014.

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 OmegaFactors Ultra Prim, straight from the product label.

Brand Natural Factors
Barcode (UPC) 068958022031
Net contents 120 Softgel(s); 1300 mg
Market status On market
Date entered into DSLD Aug 26, 2014
DSLD ID 36378
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), Gluten Free, Dairy Free, Sugar 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 OmegaFactors Ultra Prim by Natural Factors, 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)
UPC/BARCODE
068958022031
IngredientAmount% DV
Calories15 {Calories}--
Calories from Fat15 {Calories}--
Gamma-Linolenic Acid125 mg--
Total Fat1.5 Gram(s)2%
Linoleic Acid885 mg--
Oleic Acid80 mg--
Evening Primrose Oil1300 mg--

Other ingredients: Softgel

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

Suggested usage: 1 softgel 2–3 times per day or as directed by a health professional.

Precautions

Keep out of the reach of children.

Sealed for your protection. Do not use if seal is broken.

Formula

Ultra Prim(TM) is made from the highest quality evening primrose oil, a natural source of the omega-6 essential fatty acid GLA.

Evening Primrose Oil

A SOURCE OF OMEGA-6 GLA

Brand IP Statement(s)

Ultra Prim(TM) uses an exclusive extraction process that gently crushes the seed to release its nutritional oil without the application of external heat or harmful solvents like alcohol, hexane, and organic chlorines.

General Statements

Manufactured by Natural Factors to ensure safety and potency in accordance with Good Manufacturing Practices (GMP) of the FDA and Health Canada.

PRODUCT OF CANADA

Recyclable container and label.

Formulation

Contains no artificial colors, preservatives, or sweeteners; no dairy, starch, sugar, wheat, gluten, yeast, soy, corn, egg, fish, shellfish, salt, tree nuts, or GMOs.

HEXANE FREE - CHEMICAL FREE

Storage

For freshness, store in a cool, dry place.

Seals/Symbols

Purity&Potency Guaranteed

FDA Statement of Identity

DIETARY SUPPLEMENT

General

R0

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

See for yourself

OmegaFactors Ultra Prim by Natural Factors label

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

OmegaFactors Ultra Prim 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 OmegaFactors Ultra Prim by Natural Factors

These are the 4 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

125 mg per serving

Linoleic Acid

885 mg per serving

Oleic Acid

Interacts with
86 drugs
80 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

Evening Primrose Oil

Interacts with
233 drugs
1300 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 Oil monograph & interactions

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

Interaction report

OmegaFactors Ultra Prim by Natural Factors Drug Interactions

Want to check YOUR meds against OmegaFactors Ultra Prim?

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 Oil 233
Oleic Acid 86

Individual Drug Interactions

The ingredients in OmegaFactors Ultra Prim interact with 308 drugs. Click any drug to see the details.

2 of the 4 ingredients in OmegaFactors Ultra Prim interact with drugs. Each result below shows which ingredient is responsible. Evening Primrose Oil Oleic Acid

Each ingredient & the kinds of drugs it affects

For each ingredient in OmegaFactors Ultra Prim 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 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

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 OmegaFactors Ultra Prim, from the product label.

Natural Factors

See all Natural Factors products
Name
Natural Factors Canada
Pharmacist Counseling Corner

OmegaFactors Ultra Prim by Natural Factors: Common Questions

Does OmegaFactors Ultra Prim by Natural Factors interact with any medications?
Yes. Based on its ingredients, OmegaFactors Ultra Prim 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?
OmegaFactors Ultra Prim contains 4 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.
What is evening primrose oil for?
Evening primrose oil is made from seeds of the evening primrose plant and contains fatty acids including gamma-linolenic acid. In this product it's combined with other plant-derived fatty acids. The research supports only limited uses — it's possibly effective for high cholesterol and heart disease (via the oleic acid), but the evidence for other conditions it's sometimes marketed for, like asthma or breast pain, is weak or absent.
Can I take this if I'm on a blood thinner?
No — you need to talk with your doctor first. Evening primrose oil in this product carries a Moderate risk of increasing bleeding when combined with blood thinners like warfarin or antiplatelet drugs like aspirin, because it may reduce platelet clumping. Your doctor may advise you to skip it or to monitor you closely.
What are the most common side effects?
Evening primrose oil most often causes gastrointestinal side effects: abdominal pain, diarrhea, bloating, nausea, and vomiting. Some people report dizziness, headache, rash, or acne. Serious side effects are rare, but the long-term safety profile isn't well studied.
Is it safe to take while pregnant?
Evening primrose oil is rated possibly safe during pregnancy, but the evidence is unclear and some reports raise concerns, so safety data are limited. Oleic acid from food is fine, but concentrated supplement doses haven't been well studied in pregnancy. Talk with your doctor or pharmacist before taking this if you're pregnant.
Can I take this with my diabetes medication?
You should check with your doctor first. The oleic acid in this product theoretically increases the effects of blood sugar medications, which could lower your glucose more than expected. Your doctor may want to monitor your levels or adjust your dose.
Does this product actually lower cholesterol?
The oleic acid in OmegaFactors Ultra Prim is rated possibly effective for high cholesterol and heart disease, but the evidence is preliminary — it's not a proven treatment. If you're interested in it for cholesterol, talk with your doctor about whether the evidence supports it for your situation and how it fits into your overall plan.

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.

OmegaFactors Ultra Prim label
Go deeper

The Full Monographs Behind OmegaFactors Ultra Prim’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

OmegaFactors Ultra Prim'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
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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

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