Evening Primrose Oil 1,300 mg Ingredients & Drug Interactions
by Ron Teeguarden Nutraceuticals
What is this page for?
First and foremost: checking Evening Primrose Oil 1,300 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
Evening Primrose Oil 1,300 mg is a dietary supplement by Ron Teeguarden Nutraceuticals with 1 active ingredient. Its ingredients are commonly taken for eczema and skin health, pms symptoms, breast pain (mastalgia).Based on those ingredients, 309 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Evening Primrose seed Oil. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Evening Primrose Oil 1,300 mg by Ron Teeguarden Nutraceuticals
Ask about any prescription or over-the-counter medication and we check it for interactions with Evening Primrose Oil 1,300 mg by Ron Teeguarden Nutraceuticals — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
Ask the Pharmacist
A licensed pharmacist will answer your question by email — free, usually within 24 hours.
Got it — thank you!
A licensed pharmacist will answer within 24 hours. Keep an eye on your email (worth checking spam, just in case).
HelloPharmacist Scorecard of Evening Primrose Oil 1,300 mg by Ron Teeguarden Nutraceuticals
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.
What’s inside
Full disclosure
This softgel contains 1,300 mg of evening primrose oil and its component fatty acids. The four active ingredients are oleic acid, palmitic acid, cis-linoleic acid, and gamma-linoleic acid — the same fats naturally present in evening primrose seed oil.
The capsule itself is made from gelatin, glycerin, and water.
Does it work?
Couldn't assess
Oleic acid, one of the main components in this product, is rated possibly effective for high cholesterol (hypercholesterolemia) and coronary heart disease. The other fatty acids in evening primrose oil — cis-linoleic acid and gamma-linoleic acid — have no effectiveness data on file in our records.
We don't hold information on palmitic acid's effectiveness either.
How safe is it?
Some data gaps
Oleic acid from food sources like olive oil is generally well tolerated and considered safe when consumed in normal dietary amounts. However, concentrated supplements of oleic acid (and by extension, evening primrose oil supplements) haven't been well studied in pregnancy or while breastfeeding.
The safety data available covers only food-level doses, not supplement-level concentrations. If you're pregnant, nursing, or planning to become pregnant, talk with your doctor or pharmacist before taking this product.
Meds to double-check
Moderate interaction found
If you take any antidiabetes drug (medication that lowers blood sugar), double-check with your doctor or pharmacist before adding this supplement — oleic acid may increase how strongly these drugs work and could lower your blood sugar more than intended.
The bottom line
Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and some safety-information gaps remain.
Evening primrose oil may help with cholesterol and heart health based on its oleic acid content, though the evidence is preliminary. The main caution is if you take diabetes medications — this product might strengthen their blood-sugar-lowering effect.
If you're pregnant or breastfeeding, check with your doctor or pharmacist first, since supplement-level doses haven't been studied in those situations. Run your medications through the checker on this page before you start.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 1 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jul 25, 2024.
This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed
General information
Key facts about Evening Primrose Oil 1,300 mg, straight from the product label.
| Brand | Ron Teeguarden Nutraceuticals |
|---|---|
| Net contents | 60 Softgel(s) |
| Market status | On market |
| Date entered into DSLD | Jul 25, 2024 |
| DSLD ID | 316674 |
| Product type | Fat/fatty Acid |
| Supplement form | Softgel Capsule |
| Dietary claims / uses | Nutrient, All Other |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free |
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 1,300 mg by Ron Teeguarden Nutraceuticals, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Calories | 12 Calorie(s) | -- |
| Oleic Acid | 70 mg | -- |
| Total Fat | 1.5 Gram(s) | 2% |
| Palmitic Acid | 78 mg | -- |
| Evening Primrose seed Oil | 1300 mg | -- |
| cis-Linoleic acid | 925 mg | -- |
| gamma-Linoleic acid | 117 mg | -- |
Other ingredients: Gelatin, Glycerin, Water
Tap any ingredient to jump to its full detail below.
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 sugar, salt, dairy, yeast, wheat, gluten, corn, soy, preservatives, artificial colors or flavors.
Hexane free
Suggested/Recommended/Usage/Directions
Suggested use: As a dietary supplement, adults take one (1) softgel capsule, two (2) or three (3) times daily with meals, or as directed by a health care professional.
Storage
Store in a cool, dry place and away from direct light.
Precautions
Keep out of reach of children.
FDA Statement of Identity
Dietary Supplement
Seals/Symbols
Quality and potency guaranteed
Formula
Our Evening Primrose Oil 1,300 mg is 100% pure cold expeller pressed and hexane free. It is derived from the seeds of the Evening Primrose, a high source of Gamma-Linolenic Acid.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Evening Primrose Oil 1,300 mg by Ron Teeguarden Nutraceuticals label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Evening Primrose Oil 1,300 mg by Ron Teeguarden Nutraceuticals
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Softgel Capsule(s) Dosage formSoftgel Capsule Servings per container60 Amounts shown are per serving.
Evening Primrose seed Oil
Interacts with234 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 bre...
Evening Primrose seed Oil monograph & interactions- › Oleic Acid
- › Palmitic Acid
- › Cis-Linoleic acid
- › Gamma-Linoleic acid
Other (inactive) ingredients: Gelatin, Glycerin, Water. These complete the product’s ingredient list but are not active constituents.
Evening Primrose Oil 1,300 mg by Ron Teeguarden Nutraceuticals Drug Interactions
HelloPharmacist Interaction Report
Evening Primrose Oil 1,300 mg by Ron Teeguarden Nutraceuticals contains oleic acid, which has documented interactions with one class of medications.
The main concern is with antidiabetes drugs (medications that lower blood sugar): oleic acid may increase their effects, potentially lowering your blood sugar more than expected. This is based on research showing that diets rich in oleic acid from olive oil decrease fasting blood sugar levels compared to other fat sources.
Read the full breakdown — every affected drug type, severity by severity
Altogethe, these interactions span 86 individual medications. We were not able to check several other ingredients in this product — palmitic acid, cis-linoleic acid, and gamma-linoleic acid — so we can't rule out additional interactions from those components.
Evening primrose seed oil itself is listed as a blend of its component parts above.
If you take any antidiabetes medication, run your exact drugs through the checker below before starting this supplement. Your doctor or pharmacist can help you decide whether the combination is safe for you and whether your blood sugar levels need monitoring.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Evening Primrose Oil 1,300 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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Evening Primrose Oil 1,300 mg interact with 309 drugs. Click any drug to see the details.
1 of the 1 ingredient in Evening Primrose Oil 1,300 mg interact with drugs. Each result below shows which ingredient is responsible. Evening Primrose seed Oil
AbciximabReoPro
How Abciximab interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Abciximab interactionAbrocitinibCibinqo
How Abrocitinib interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilCytochrome P450 2c9 (cyp2c9) Substrates, Anticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose may increase the levels and clinical effects of CYP2C9 substrates.
Read the full Evening Primrose Seed Oil + Abrocitinib interactionAcarboseGlucobay, Prandase, Precose
How Acarbose interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Oleic AcidAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oleic acid might increase the effects of antidiabetes drugs.
Read the full Oleic Acid + Acarbose interactionAcenocoumarolSintrom
How Acenocoumarol interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Acenocoumarol interactionAcepromazineAtravet
How Acepromazine interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilPhenothiazines Moderate
Interaction Summary
Theoretically, taking evening primrose oil with phenothiazines might increase the risk of convulsions.
Read the full Evening Primrose Seed Oil + Acepromazine interactionAcetaminophen, AspirinGemnisyn
How Acetaminophen, Aspirin interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Acetaminophen, Aspirin interactionAcetaminophen, Aspirin, CaffeineExcedrin, Excedrin Extra Strength, Excedrin Migraine
How Acetaminophen, Aspirin, Caffeine interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Acetaminophen, Aspirin, Caffeine interactionAcetaminophen, IbuprofenCombogesic
How Acetaminophen, Ibuprofen interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilCytochrome P450 2c9 (cyp2c9) Substrates, Anticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose may increase the levels and clinical effects of CYP2C9 substrates.
Read the full Evening Primrose Seed Oil + Acetaminophen, Ibuprofen interactionAcetohexamideDymelor
How Acetohexamide interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Oleic AcidAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oleic acid might increase the effects of antidiabetes drugs.
Read the full Oleic Acid + Acetohexamide interactionAcetylsalicylic AcidEntrophen
How Acetylsalicylic Acid interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Acetylsalicylic Acid interactionAlbiglutideTanzeum
How Albiglutide interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Oleic AcidAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oleic acid might increase the effects of antidiabetes drugs.
Read the full Oleic Acid + Albiglutide interactionAlogliptinNesina
How Alogliptin interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Oleic AcidAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oleic acid might increase the effects of antidiabetes drugs.
Read the full Oleic Acid + Alogliptin interactionAlogliptin, MetforminKazano
How Alogliptin, Metformin interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Oleic AcidAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oleic acid might increase the effects of antidiabetes drugs.
Read the full Oleic Acid + Alogliptin, Metformin interactionAlogliptin, PioglitazoneOseni
How Alogliptin, Pioglitazone interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Oleic AcidAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oleic acid might increase the effects of antidiabetes drugs.
Read the full Oleic Acid + Alogliptin, Pioglitazone interactionAlteplase, TpaActilyse, Activase
How Alteplase, Tpa interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Alteplase, Tpa interactionAluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #2
How Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interactionAluminum Hydroxide, Aspirin, Magnesium HydroxideAscriptin
How Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interactionAmitriptyline, PerphenazineEtrafon, Etrafon-A, Etrafon-Forte, Triavil
How Amitriptyline, Perphenazine interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilCytochrome P450 2c9 (cyp2c9) Substrates, Phenothiazines Moderate
Interaction Summary
Theoretically, evening primrose may increase the levels and clinical effects of CYP2C9 substrates.
Read the full Evening Primrose Seed Oil + Amitriptyline, Perphenazine interactionAnacaulase-bcdbNexoBrid
How Anacaulase-bcdb interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Anacaulase-bcdb interactionAnagrelideAgrylin
How Anagrelide interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Anagrelide interactionAnisindioneMiradon
How Anisindione interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Anisindione interactionAntidiabetes, Dipeptidyl Peptidase-4 (dpp-iv) InhibitorGlyxambi
How Antidiabetes, Dipeptidyl Peptidase-4 (dpp-iv) Inhibitor interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Oleic AcidAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oleic acid might increase the effects of antidiabetes drugs.
Read the full Oleic Acid + Antidiabetes, Dipeptidyl Peptidase-4 (dpp-iv) Inhibitor interactionAntithrombin IiiThrombate III
How Antithrombin Iii interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Antithrombin Iii interactionApixabanEliquis
How Apixaban interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Apixaban interactionArgatrobanArgatroban
How Argatroban interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Argatroban interactionAspirinAngettes 75, ASA, Asaphen, Aspirin, Caprin, Cartia +8 more
How Aspirin interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Aspirin interactionAspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #3
How Aspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium Hydroxide interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Aspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium Hydroxide interactionAspirin, ButalbitalAxotal
How Aspirin, Butalbital interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Aspirin, Butalbital interactionAspirin, Butalbital, CaffeineFiorinal
How Aspirin, Butalbital, Caffeine interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Aspirin, Butalbital, Caffeine interactionAspirin, Butalbital, Caffeine, Codeine PhosphateFiorinal w/ Codeine
How Aspirin, Butalbital, Caffeine, Codeine Phosphate interacts with Evening Primrose Oil 1,300 mg — through 1 ingredient. Tap an ingredient for the detail:
Evening Primrose Seed OilAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full Evening Primrose Seed Oil + Aspirin, Butalbital, Caffeine, Codeine Phosphate interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Evening Primrose Oil 1,300 mg with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.
Evening Primrose seed Oil
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.
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.
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.
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.
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.
Brand information
Manufacturer and brand details for Evening Primrose Oil 1,300 mg, from the product label.
Ron Teeguarden Nutraceuticals
See all Ron Teeguarden Nutraceuticals products- Name
- Ron Teeguarden Nutraceuticals
Evening Primrose Oil 1,300 mg by Ron Teeguarden Nutraceuticals: Common Questions
Does Evening Primrose Oil 1,300 mg by Ron Teeguarden Nutraceuticals interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does evening primrose oil actually help with cholesterol or heart health?
Is this safe to take while pregnant or breastfeeding?
What exactly is in this product?
Can I take this if I'm on diabetes medication?
Are there any side effects I should know about?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Evening Primrose Oil 1,300 mg is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind Evening Primrose Oil 1,300 mg’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Evening Primrose
Interacts with 234 drugsEvening 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 → Herb & supplement monographOleic Acid
Interacts with 86 drugsOleic 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 →Sources & How We Checked
Evening Primrose Oil 1,300 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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 34 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 1 reference
- 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
Evening Primrose 33 references
- 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.
- 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
- 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
- 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
- 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
- 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.
- 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
- 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..
- Das UN. The lipids that matter from infant nutrition to insulin resistance. Prostaglandins Leukot Essent Fatty Acids 2002;67:1-12. PubMed
- 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
- 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.
- 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
- Tong M. [Treatment of hyperlipemia with evening primrose oil capsules]. Zhong Xi Yi Jie He Za Zhi. 1988;8:469-71, 452-3.
- Holman CP and Bell AF. A trial of evening primrose oil in the treatment of chronic schizophrenia. J Orhtomolecular Psych 1983;12:302-304.
- 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
- 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
- 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
- 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.
- 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.
- 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.
- 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.
- 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
- 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
- Puri BK. The safety of evening primrose oil in epilepsy. Prostaglandins Leukotrienes Essential Fatty Acids 2007;77:101-3. PubMed
- 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
- Osman M, Badawi E. Evening primrose oil reducing serum lithium concentration. Ther Adv Psychopharmacol. 2016 Oct;6(5):343-44. PubMed
- 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.
- 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
- 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
- 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
- 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.
- 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
- 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
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