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Evening Primrose Oil

Natural plant oil rich in gamma-linolenic acid (GLA), traditionally used for women's health, skin conditions, and inflammatory support

Scientific nameOenothera biennis oil FormulaMixed fatty acid complex containing GLA Molecular weightVariable - oil complex g/mol CAS90028-66-3
80 absorption score
8 safety / 10
30 USD per month
6 documented interactions

Check it against something

Evidence level B

Evening Primrose Oil with:

Compatibility score 78 out of 100
78 out of 100
Works better together Compatible. Timing differs, so follow each supplement's own window.

Check it against your whole stack →

What it does

mechanism and evidence for each claim

Women's hormonal health and PMS relief

May help reduce PMS symptoms and support hormonal balance

GLA converts to anti-inflammatory prostaglandins that regulate hormonal function Evidence B-grade 6-12 weeks for hormonal benefits

Skin health and eczema management

Improves skin barrier function and may help with atopic dermatitis

GLA is essential for skin lipid barrier formation and anti-inflammatory effects Evidence B-grade 8-16 weeks for skin improvements

Anti-inflammatory support

Provides anti-inflammatory effects through GLA conversion to beneficial prostaglandins

GLA produces anti-inflammatory PGE1 instead of inflammatory mediators Evidence B-grade 4-8 weeks for anti-inflammatory effects

Menopause symptom relief

May help reduce hot flashes and other menopausal symptoms

Hormonal modulation through prostaglandin balance Evidence C-grade 8-12 weeks for menopause benefits

Joint health and rheumatoid arthritis support

May help reduce joint inflammation and improve mobility

Anti-inflammatory prostaglandins reduce joint inflammation and pain Evidence C-grade 12-24 weeks for joint benefits

Every pair we checked

12 combinations scored by the engine
Evening Primrose Oil + Caffeine No documented interaction either way No known interaction 70
Evening Primrose Oil + Creatine Monohydrate No documented interaction either way No known interaction 70
Evening Primrose Oil + Calcium Carbonate No documented interaction either way No known interaction 70
Evening Primrose Oil + Whey Protein No documented interaction either way No known interaction 70
Evening Primrose Oil + Lactase No documented interaction either way No known interaction 70
Evening Primrose Oil + Bovine Collagen No documented interaction either way No known interaction 70
Evening Primrose Oil + DHA No documented interaction either way No known interaction 70
Evening Primrose Oil + Turmeric No documented interaction either way No known interaction 70
Evening Primrose Oil + Fish Oil (EPA/DHA) No documented interaction either way No known interaction 70
Evening Primrose Oil + Vitamin D3 Protects oil from oxidation and enhances stability Works better together 78
Evening Primrose Oil + Magnesium Oxide Supports hormonal balance and PMS relief Works better together 78
Evening Primrose Oil + Omega-3 + Curcumin + Vitamin D Triple Anti-Inflammatory Formula Essential for balanced inflammatory response and optimal GLA benefits Works better together 82

Dosage

With meals for absorption
Daily1,000-3,000 mg oil
General womens health1,000-2,000 mg oil daily
Pms relief1,000-3,000 mg oil daily
Skin health2,000-4,000 mg oil daily
Menopause support1,000-2,000 mg oil daily

When to expect it

First Effects4-6 weeks for initial hormonal and skin benefits
Peak Benefits12-16 weeks for maximum women's health and skin benefits
Deficiency DevelopmentGLA deficiency common due to impaired enzyme function
Toxicity OnsetGenerally safe - monitor for seizure risk in predisposed individuals

How to measure it

$200-400
MarkerGLA levels, omega-6/omega-3 ratio, inflammatory markers, hormone levels
OptimalAdequate GLA levels, balanced fatty acid ratios, stable hormones
Deficient belowLow GLA levels, hormonal imbalances
FrequencyMonitor every 3-6 months during supplementation

What people actually reported to the FDA

CAERS, 31 reports naming it as the suspect

Most reported effects

Hypersensitivity 5
Pruritus 5
Malaise 4
Headache 4
Alanine aminotransferase increased 3
Named as the suspect 31 reports of 58 that mention it at all
Serious outcome 75% hospitalisation, emergency room or worse
Other Serious or Important Medical Event20
Hospitalization10
Visited a Health Care Provider8

Reports are voluntary and unverified — they record what someone experienced while taking something, not what the compound caused. Counts skew towards products people take a lot of, and a serious outcome is more likely to be reported than a mild one, so these are not rates. How we filter them →

What actually reaches you

The label counts the carrier, your body does not
Absorption Very high 80 of 100 · best absorbed form of this compound
Delivered daily 1600 mg
Cost per 100 mg delivered $0.06 comparative — uses the absorption score, not a measured percentage

Works better with

3 documented
+
Omega 3 Fatty Acids

Essential for balanced inflammatory response and optimal GLA benefits

Omega-3s prevent GLA from becoming pro-inflammatory · level A
+
Vitamin E

Protects oil from oxidation and enhances stability

Vitamin E acts as antioxidant protecting fatty acids · level B
+
Magnesium

Supports hormonal balance and PMS relief

Magnesium works synergistically for women's hormonal health · level B

What not to take with Evening Primrose Oil

3 documented
!
Phenothiazines

Evening primrose oil may increase seizure risk with these drugs

May lower seizure threshold in predisposed individuals · high significance
!
Trans Fats

Trans fats interfere with GLA metabolism and benefits

Disrupts fatty acid metabolism and enzyme function · moderate significance
!
Excessive Omega 6 Oils

High linoleic acid intake may reduce evening primrose oil effectiveness

Competes for enzymes and may promote inflammation · moderate significance

Medication interactions

Discuss these with a pharmacist before combining
anticonvulsants Moderate

May lower seizure threshold and reduce drug effectiveness

What to do: Avoid in epileptic patients or use with careful monitoring

anticoagulants Minor

May enhance blood-thinning effects

What to do: Monitor bleeding time if using high doses

Available forms

bioavailability compared
Cold-pressed evening primrose oil (8-10% GLA) 80

Cold-pressed evening primrose oil (8-10% GLA): Natural GLA source, Traditional use, Well-researched, Good safety profile

Food sources

before you supplement
Evening primrose oil supplements 8-10% GLA (80-100 mg GLA per 1000mg oil) · 80
Evening primrose seeds Natural source but not practical for consumption · 75
Borage oil (higher GLA alternative) 20-24% GLA (200-240 mg GLA per 1000mg oil) · 85
Black currant oil (GLA alternative) 15-18% GLA (150-180 mg GLA per 1000mg oil) · 80

Too little

deficiency signs
  • GLA deficiency symptoms (evening primrose oil addresses):
  • Severe PMS symptoms including mood swings and cramping
  • Skin problems including eczema and poor barrier function
  • Hormonal imbalances and menstrual irregularities
  • Chronic inflammation despite adequate omega-3 intake
  • Joint pain and stiffness from inflammatory conditions
  • Poor reproductive health and fertility issues

Too much

toxicity signs
  • Generally safe with potential for mild adverse effects:
  • Increased seizure risk in epileptic individuals
  • Digestive discomfort including nausea and loose stools
  • Headaches with high doses in sensitive individuals
  • Safe for long-term use in most healthy individuals

Who benefits most

pms-menstrual-issues

Traditional use and research support for PMS symptom relief

1,000-3,000 mg oil daily (80-240 mg GLA)
skin-health-eczema

GLA essential for skin barrier function and eczema management

2,000-4,000 mg oil daily (160-320 mg GLA)
menopause-symptoms

May help with hot flashes and hormonal transition

1,000-2,000 mg oil daily (80-160 mg GLA)
inflammatory-conditions

Anti-inflammatory GLA for chronic inflammatory conditions

2,000-4,000 mg oil daily (160-320 mg GLA)
women-hormonal-balance

General hormonal support and women's wellness

1,000-2,000 mg oil daily (80-160 mg GLA)

Where to buy it

compare forms first

Look for Evening Primrose Oil at 1,000-3,000 mg oil per serving. The form that matters here is Cold-pressed evening primrose oil (8-10% GLA).

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What else affects it

Beyond other supplements
!
Trans fats

Trans fats interfere with GLA metabolism and benefits

Disrupts fatty acid metabolism and enzyme function
!
Excessive omega 6 oils

High linoleic acid intake may reduce evening primrose oil effectiveness

Competes for enzymes and may promote inflammation

How it works

  • Provides gamma-linolenic acid (GLA) which converts to beneficial prostaglandins
  • GLA bypasses rate-limiting delta-6-desaturase enzyme
  • Produces anti-inflammatory prostaglandin E1 (PGE1)
  • Essential for skin ceramide synthesis and barrier function
  • Modulates hormonal signaling through prostaglandin pathways
  • Supports healthy inflammatory balance in reproductive tissues

Key findings

what the evidence supports
  • Mixed evidence for PMS relief with some positive studies
  • Limited but promising evidence for atopic dermatitis
  • Good safety profile with minimal adverse effects
  • Quality and GLA content vary significantly between products

Sources: NIH Examine.com · data reviewed 2026-08-02

Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →

Common questions

What are the benefits of Evening Primrose Oil?

Documented effects: Women's hormonal health and PMS relief; Skin health and eczema management; Anti-inflammatory support; Menopause symptom relief. May help reduce PMS symptoms and support hormonal balance

How much Evening Primrose Oil should you take per day?

The common daily range is 1,000-3,000 mg oil. By goal — general womens health: 1,000-2,000 mg oil daily; pms relief: 1,000-3,000 mg oil daily; skin health: 2,000-4,000 mg oil daily; menopause support: 1,000-2,000 mg oil daily.

When is the best time to take Evening Primrose Oil?

With meals for absorption. First effects are typically reported within 4-6 weeks for initial hormonal and skin benefits.

What are the side effects of Evening Primrose Oil?

At excessive doses: Generally safe with potential for mild adverse effects:, Increased seizure risk in epileptic individuals, Digestive discomfort including nausea and loose stools, Headaches with high doses in sensitive individuals, Safe for long-term use in most healthy individuals. Safety rating at normal doses is 8 out of 10.

What should you not take with Evening Primrose Oil?

Separate it from Phenothiazines, Trans Fats, Excessive Omega 6 Oils by two to four hours. Evening primrose oil may increase seizure risk with these drugs

Does Evening Primrose Oil interact with medications?

Documented interactions with anticonvulsants, anticoagulants. Discuss these with a pharmacist before combining.

How do you know if you need Evening Primrose Oil?

The marker is GLA levels, omega-6/omega-3 ratio, inflammatory markers, hormone levels, optimal range Adequate GLA levels, balanced fatty acid ratios, stable hormones. Common deficiency signs: GLA deficiency symptoms (evening primrose oil addresses):, Severe PMS symptoms including mood swings and cramping, Skin problems including eczema and poor barrier function, Hormonal imbalances and menstrual irregularities.