Evening Primrose Oil
10 benefits mapped to clinical evidence across supplements.
Dose per serving from products
334 products in our catalogue print how much Evening Primrose Oil a serving holds.
Most common: 250 mg to 500 mg, 31% of 334 products.
| Dose per serving | Products |
|---|---|
| 25 mg or less | 11 |
| 25 mg to 50 mg | 20 |
| 50 mg to 100 mg | 20 |
| 100 mg to 250 mg | 15 |
| 250 mg to 500 mg | 102 |
| 500 mg to 1 g | 66 |
| 1 g to 2.5 g | 100 |
Dose per serving from research
17 study groups in 13 studies say how much Evening Primrose Oil participants took a day.
These are the doses the studies gave. They are not a recommendation.
Most common: 1 g to 2.5 g, 35% of 17 study groups.
| Daily dose | Study groups |
|---|---|
| 500 mg or less | 1 |
| 500 mg to 1 g | 4 |
| 1 g to 2.5 g | 6 |
| 2.5 g to 5 g | 4 |
| 5 g to 10 g | 2 |
Benefit Evidence
Hot flashes/sweating â
Irritability, CRP â
Hot flash severity -42%
Research sources
Skin hydration (4)
- Effect of topically applied evening primrose oil on epidermal barrier function in atopic dermatitis as a function of vehicle
PubMed ID: 10442214
Topical EPO in an appropriate vehicle increased stratum corneum hydration and reduced TEWLâdirect, strong evidence for increased skin hydration.
- Oral omega-6 essential fatty acid treatment in contact lens associated dry eye
PubMed ID: 18313350
Contactâlens related dryâeye trial: EPO improved dryness symptoms and increased tear meniscus height.
- Evening primrose oil is effective in atopic dermatitis: a randomized placebo-controlled trial
PubMed ID: 19052401
EPO produced large improvements in atopic dermatitis signs, including dryness.
- Effect of Evening Primrose Oil Supplementation on Selected Parameters of Skin Condition in a Group of Patients Treated with Isotretinoin-A Randomized Double-Blind Trial
PubMed ID: 35889936
Randomized trial adding EPO to isotretinoin prevented isotretinoin-induced decrease in skin hydration (large, clinically meaningful effect on hydration).
Hormone balance (3)
- Efficacy and Safety of Nutraceutical on Menopausal Symptoms in Post-Menopausal Women: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial
PubMed ID: 33331798
Multi-ingredient nutraceutical including EPO reduced hot flashes and irritability vs placeboâsuggestive of hormonal/vasomotor symptom benefit but not attributable to EPO alone.
- The effect of oral evening primrose oil on menopausal hot flashes: a randomized clinical trial
PubMed ID: 23625331
Menopausal trial found modest reductions in hotâflash severity and QoL improvements, consistent with some endocrine symptom relief.
- Effectiveness of a herbal formula in women with menopausal syndrome
PubMed ID: 22105039
Herbal 4-ingredient product including EPO improved menopausal symptom scores vs placebo; EPO was one component so attribution uncertain.
Inflammation (3)
- Supplementation with omega-3 or omega-6 fatty acids attenuates platelet reactivity in postmenopausal women
PubMed ID: 35791734
Strong evidence: crossover trial showed durable reductions in platelet aggregation, integrin activation, and dense granule secretionâconsistent with reduced activation/inflammatory potential.
- Clinical Benefits of n-3 PUFA and ɤ-Linolenic Acid in Patients with Rheumatoid Arthritis
PubMed ID: 28346333
RA trial: fish oil and fish oil+EPO reduced disease activity and pain (inflammatory disease); although fish oil is major active agent, combination showed lower inflammatory outcomes.
- Alteration of delta-6-desaturase (FADS2), secretory phospholipase-A2 (sPLA2) enzymes by Hot-nature diet with co-supplemented hemp seed, evening primrose oils intervention in multiple sclerosis patients
PubMed ID: 26365444
RRMS co-supplementation produced clinical and membrane-enzyme changes consistent with anti-inflammatory/immunomodulatory effects (EPO combined with hemp seed oil and diet).
Nerve health (3)
- Alteration of delta-6-desaturase (FADS2), secretory phospholipase-A2 (sPLA2) enzymes by Hot-nature diet with co-supplemented hemp seed, evening primrose oils intervention in multiple sclerosis patients
PubMed ID: 26365444
RRMS co-supplementation improved disability/functional scores â suggestive of neurologic benefit though EPO was combined with other interventions.
- Immunomodulatory and therapeutic effects of Hot-nature diet and co-supplemented hemp seed, evening primrose oils intervention in multiple sclerosis patients
PubMed ID: 24050582
Hemp seed + EPO + diet in MS improved EDSS and relapse rateâclinically relevant neurologic benefit in a demyelinating disease, though intervention was multi-component.
- Effects of evening primrose oil on treating painful diabetic neuropathy: a randomized, double-blind, clinical trial
PubMed ID: 40418820
Randomized double-blind trial showed significant reductions in pain intensity and neuropathic symptom scores in painful diabetic neuropathy â direct, high-quality evidence for nerve comfort.
Skin health (3)
- Effect of topically applied evening primrose oil on epidermal barrier function in atopic dermatitis as a function of vehicle
PubMed ID: 10442214
Topical EPO in a water-in-oil emulsion improved skin barrier (lower TEWL, higher hydration) in atopic dermatitisâdirect, high-relevance evidence for skin health.
- Evening primrose oil is effective in atopic dermatitis: a randomized placebo-controlled trial
PubMed ID: 19052401
Randomized trial showed marked clinical improvement in atopic dermatitis signs/symptoms with EPO.
- Effect of Evening Primrose Oil Supplementation on Selected Parameters of Skin Condition in a Group of Patients Treated with Isotretinoin-A Randomized Double-Blind Trial
PubMed ID: 35889936
As adjunct to isotretinoin, EPO increased skin hydration versus isotretinoin alone (clinically relevant adjunct effect).
Immune support (2)
- Alteration of delta-6-desaturase (FADS2), secretory phospholipase-A2 (sPLA2) enzymes by Hot-nature diet with co-supplemented hemp seed, evening primrose oils intervention in multiple sclerosis patients
PubMed ID: 26365444
RRMS trial with clinical and membrane enzyme improvements suggests immunomodulatory effects with EPO+hemp seed oil and diet.
- Erythrocyte membrane fatty acids in multiple sclerosis patients and hot-nature dietary intervention with co-supplemented hemp-seed and evening-primrose oils
PubMed ID: 24311880
Coâsupplementation trial in RRMS reported improved erythrocyte PUFAs and favourable immunologic/EDSS changes, though EPO's isolated effect is unclear.
Joint comfort (2)
- Evening primrose oil in patients with rheumatoid arthritis and side-effects of non-steroidal anti-inflammatory drugs
PubMed ID: 1913008
Small RA trial showed a modest early reduction in morning stiffness with GLA (EPO source).
- Clinical Benefits of n-3 PUFA and ɤ-Linolenic Acid in Patients with Rheumatoid Arthritis
PubMed ID: 28346333
RA trial: fish oil and fish oil+EPO both reduced DAS28 and painâmeaningful reduction in joint symptoms though fish oil likely major contributor.
Skin soothing (2)
- Evening primrose oil is effective in atopic dermatitis: a randomized placebo-controlled trial
PubMed ID: 19052401
Large responder difference in atopic dermatitis (96% vs 32% improved) implies fewer flares/clinical activity with EPO in this study.
- Effect of topically applied evening primrose oil on epidermal barrier function in atopic dermatitis as a function of vehicle
PubMed ID: 10442214
Topical EPO improved barrier metrics in atopic dermatitis, which can reduce flare risk; study measured barrier rather than flare frequency.
Mood balance (1)
- Impact of evening primrose oil consumption on psychological symptoms of postmenopausal women: a randomized double-blinded placebo-controlled clinical trial
PubMed ID: 31738736
Large RCT in postmenopausal women showed clear, statistically significant reduction in psychological symptom scores.
Eye health (1)
- Oral omega-6 essential fatty acid treatment in contact lens associated dry eye
PubMed ID: 18313350
Randomized trial in contact lens wearers: EPO improved dryness symptoms, lens comfort and increased tear meniscus height.
Similar by evidence
Supplements the same benefits carry qualifying findings for â a fact about the evidence graph, not a recommendation to swap.
Products with Evening Primrose Oil
Search all431 products whose verified label declares Evening Primrose Oil â not every bottle that mentions it in a title.
Being studied right now
Recruiting clinical trials registered on ClinicalTrials.gov. A trial in progress has no result yet â this is what the field is asking, not what it found.