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Dietary supplement

Evening Primrose Oil 1000 mg Ingredients & Drug Interactions

by Esmond Natural

Softgel Capsule Category: Fat/fatty Acid
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

Evening Primrose Oil 1000 mg is a dietary supplement by Esmond Natural with 1 active ingredient. Its ingredients are commonly taken for eczema and skin health, pms symptoms, breast pain (mastalgia).Based on those ingredients, 233 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Evening Primrose Oil. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Evening Primrose Oil 1000 mg by Esmond Natural

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

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: evening primrose oil at 1000 mg per softgel capsule. Evening primrose oil is extracted from the seeds of the evening primrose plant and is a rich source of essential fatty acids, particularly linoleic acid and gamma linolenic acid (GLA).

The inactive ingredients are gelatin and vegetable glycerin, which form the softgel capsule.

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 — see Evening Primrose's own graded uses on its monograph.

Why this rating?
  • The label markets this product for: Women's health and PMS support.
  • We looked for evidence on: Premenstrual syndrome (PMS), Mastalgia, Menopausal symptoms, Hormonal balance, Menstrual health.
  • 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 Menopausal symptoms, Premenstrual syndrome (PMS).

The evidence for evening primrose oil is mixed and mostly limited. For asthma, it's rated possibly ineffective.

For breast pain (mastalgia), the evidence suggests it's likely ineffective. For other uses — including acne, ADHD, induced abortion, and hysteroscopy — we don't yet have enough reliable evidence to know whether it works.

If you're considering this supplement for a specific health reason, talk with your pharmacist or doctor about what the current research actually shows for your situation.

The evidence, ingredient by ingredient Evening Primrose

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Evening primrose oil is generally well tolerated in the short term, though long-term safety data are limited. The most common side effects when taken by mouth are mild digestive complaints: abdominal pain, bloating, diarrhea, indigestion, gas, nausea, and vomiting.

Some people have reported skin rash, acne, dizziness, or headache. There's a single case report of seizures in a patient taking evening primrose oil during anesthesia, though other medications the patient was taking made it unclear whether evening primrose was the cause.

For pregnancy, the safety data are uncertain — it's rated possibly safe, but evidence is limited. The data note that concerns have been raised, so it's best to avoid it during pregnancy unless your doctor directs otherwise.

For breastfeeding, it's also rated possibly safe, meaning there isn't enough reliable information to know either way. Talk with your doctor or pharmacist for personalized advice if you're pregnant, planning to become pregnant, or breastfeeding.

Side effects, ingredient by ingredient Evening Primrose

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

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

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Evening Primrose.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; lithium.
  • For scale: 233 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.

Check your exact medications if you take blood thinners (anticoagulants or antiplatelet drugs) — evening primrose oil may increase bleeding risk. Also double-check with your pharmacist if you're on lithium, any psychiatric medication (especially older ones like phenothiazines), the HIV medication lopinavir/ritonavir, or any drug metabolized by your liver's CYP2C9 enzyme.

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 may help some people, but the evidence for most uses is weak or absent. If you take blood thinners, lithium, psychiatric medications, or HIV protease inhibitors, you need to check with your pharmacist before starting this supplement — the interactions are real and potentially important.

Otherwise, it's generally well tolerated for short-term use, though digestive side effects are common.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Jul 25, 2018.

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 1000 mg, straight from the product label.

Brand Esmond Natural
Barcode (UPC) 641399083276
Net contents 60 Softgel(s)
Market status On market
Date entered into DSLD Jul 25, 2018
DSLD ID 178627
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 Evening Primrose Oil 1000 mg by Esmond Natural, 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
641399083276
IngredientAmount% DV
Evening Primrose Oil1000 mg--

Other ingredients: Gelatin, Vegetable Glycerin

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
General Statements

Body Integrated health Naturally driven for long lasting health.

Body

Made in USA

Formula

Evening primose is a natural source of the unsaturated fatty acid, gamma-linolenic acid (GLA), that promotes women's health and helps provide nutritional support for PMS.

Standardized GLA 9% Providing 90 mg GLA(9%)

Promotes women's health Natural support for women with PMS

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease.

Formulation

No artificial color, flavor or sweetener, no preservatives, no sugar, no starch, no milk, no lactose, no soy, no gluten, no wheat, no yeast, no fish. Sodium free.

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Directions: For adults, take one (1) softgel three times daily, preferably with a meal.

Precautions

Warning: If your are pregnant, nursing, taking any medications or planning any medical procedure, consult your doctor if any adverse reactions occur.

Keep out of reach of children.

Tamper resistant: Do not use if imprinted seal under cap is broken or missing.

Storage

Store in a dry place and avoid excessive heat.

See for yourself

Evening Primrose Oil 1000 mg by Esmond Natural label

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

What’s inside

The Ingredients in Evening Primrose Oil 1000 mg by Esmond Natural

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Softgel(s) Dosage formSoftgel Capsule Amounts shown are per serving.

Evening Primrose Oil

Interacts with
233 drugs
1000 mg per serving Form: Gamma-Linolenic Acid, Cold-Pressed

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

Evening Primrose Oil monograph & interactions

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

Interaction report

Evening Primrose Oil 1000 mg by Esmond Natural Drug Interactions

Want to check YOUR meds against Evening Primrose Oil 1000 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
233Drugs
148 Moderate 85 Minor

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in Evening Primrose Oil 1000 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 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
The maker

Brand information

Manufacturer and brand details for Evening Primrose Oil 1000 mg, from the product label.

Esmond Natural

See all Esmond Natural products
Name
Esmond Natural Inc.
City
Irwindale
State
CA
ZipCode
91706
Phone Number
1-800-814-6866
Web Address
www.esmondnatural.com
Pharmacist Counseling Corner

Evening Primrose Oil 1000 mg by Esmond Natural: Common Questions

Does Evening Primrose Oil 1000 mg by Esmond Natural interact with any medications?
Yes. Based on its ingredients, Evening Primrose Oil 1000 mg has a known interaction with 233 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 1000 mg contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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 and where does it come from?
Evening primrose oil comes from the seeds of the evening primrose plant. It's rich in essential omega-6 fatty acids, including gamma linolenic acid (GLA). This product gives you 1000 mg per softgel capsule.
Can I take this if I'm pregnant or breastfeeding?
The safety data for both pregnancy and breastfeeding are uncertain — it's rated possibly safe, but there isn't enough reliable information either way. The data do note some concerns were raised about pregnancy use. Talk with your doctor or pharmacist before taking it if you're pregnant, trying to conceive, or breastfeeding.
What are the most common side effects?
Most side effects are digestive: abdominal pain, bloating, diarrhea, indigestion, gas, nausea, and vomiting. Some people have reported dizziness, headache, skin rash, or acne. These tend to be mild, though long-term safety data are limited.
Does evening primrose oil actually work for asthma or other conditions?
The evidence is weak. For asthma, it's rated possibly ineffective. For breast pain, it's likely ineffective. For acne and ADHD, we don't have enough reliable evidence yet to know if it works. Talk with your pharmacist about whether it makes sense for your specific use.
Why do I need to check my blood thinners before taking this?
Evening primrose oil contains gamma linolenic acid, which may reduce blood clotting. If you're on a blood thinner like warfarin or aspirin, combining them could increase your bleeding risk. Your pharmacist can tell you whether it's safe in your situation.
Is there anything else in this product besides evening primrose oil?
No active ingredients besides the 1000 mg of evening primrose oil. The softgel capsule itself is made from gelatin and vegetable glycerin — those are inactive ingredients that hold the oil together.

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

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Ask a pharmacist

Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Evening Primrose Oil 1000 mg label
Go deeper

The Full Monographs Behind Evening Primrose Oil 1000 mg’s Ingredients

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

Sources

Sources & How We Checked

Evening Primrose Oil 1000 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 33 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.

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

See these in context on the Evening Primrose monograph →

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

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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