Evening Primrose Oil: 7 Facts on Eczema, PMS, Breast Pain and Safety
Evening Primrose Oil: What Is It Exactly?
Evening primrose oil is pressed from the seeds of Oenothera biennis, a wild North American plant whose yellow flowers open in the evening. The oil is rich in omega-6 fatty acids, mainly gamma-linolenic acid (GLA), which makes up about 8-10% of it. Evening primrose oil is heavily marketed for women’s health and skin, but modern research is much weaker than the advertising. Here are 7 facts to help you make an informed decision before you buy.
1. What Is GLA and Why Does It Matter?
In the body, GLA is converted into hormone-like compounds called prostaglandins that help regulate inflammation and skin health. An older theory held that some women with premenstrual symptoms or breast pain could not convert fatty acids properly, and that evening primrose oil would correct this. Later trials did not clearly support that idea. GLA is also found in borage oil and blackcurrant seed oil, while most people already get plenty of omega-6 fats from ordinary food.
2. Evening Primrose Oil and Eczema
Atopic eczema is the best-known traditional use. However, a 2013 Cochrane systematic review that pooled dozens of trials concluded that taking the oil by mouth does not improve eczema symptoms more than a placebo. Regular moisturisers, avoiding irritants and the creams your dermatologist prescribes remain the real treatment. Never replace a child’s prescribed eczema treatment with a supplement.
3. Cyclical Breast Pain
Evening primrose oil was once commonly recommended for breast pain linked to the menstrual cycle, but newer and better-designed trials found no clear difference from placebo, and many guidelines no longer list it as a first choice. A well-fitting supportive bra and cutting back on caffeine are simple first steps. Any breast lump, one-sided pain unrelated to your cycle, nipple discharge or skin change needs a prompt medical examination, not a supplement.
4. PMS and Menopause Hot Flashes
Most premenstrual syndrome trials of evening primrose oil showed no clear benefit; you will find better-supported options such as calcium and vitamin B6 in our guide to PMS supplements. For menopausal hot flashes, one small trial reported a modest reduction in severity but not in frequency, which is not enough for a recommendation. For options at that stage of life, read menopause herbs.
| Common use | What the evidence says |
|---|---|
| Eczema | No difference from placebo in systematic reviews |
| Cyclical breast pain | Mixed results; newer trials mostly negative |
| PMS | No clear benefit in most trials |
| Hot flashes | Small drop in severity in one small trial |
5. Evening Primrose Oil Safety: Bleeding, Surgery and Medicines
- Mild side effects: upset stomach, soft stools or headache in some people; taking it with food helps.
- Blood thinners: it may increase bleeding risk with warfarin, aspirin, clopidogrel or newer anticoagulants, so do not combine them without your doctor.
- Surgery: stop it at least two weeks before any operation or tooth extraction.
- Seizures: older reports described seizures in people taking phenothiazine antipsychotics, so anyone with a seizure history or on these medicines should ask a doctor first.
- If you take regular medicines or live with a chronic illness, check with your doctor or pharmacist before starting.
6. Evening Primrose Oil, Pregnancy and the Labour Myth
A popular tip suggests taking evening primrose oil, or inserting capsules vaginally, in late pregnancy to ripen the cervix and speed up labour. The available studies have not shown that it shortens labour or reduces interventions, and one older study linked it to more birth complications. Do not use evening primrose oil during pregnancy or breastfeeding unless your obstetrician decides so; the label itself says adults only, and to consult a physician if pregnant or nursing.
7. How to Take It Correctly
| Item | Detail |
|---|---|
| Per softgel | 1,300 mg cold-pressed oil, about 104-130 mg GLA |
| Bottle | 60 softgels (bovine gelatin), 60 servings |
| How to take | 1 softgel 1 to 2 times daily with food |
| Who for | Adults only; ask a doctor if pregnant, nursing or on medication |
These are the details of NOW Super Primrose 1300 mg. If you try it for a specific goal, note your symptoms before you start and review the difference after about three months; if nothing has changed, there is no reason to continue. Store it in a cool, dry place out of reach of children.
Evening Primrose Oil and Other Women’s Health Products
Each product has a different purpose, so avoid stacking supplements without a clear reason. Inositol, for example, is mainly studied in polycystic ovary syndrome and fertility; read inositol for fertility. Products available at No Style Like:
- NOW Super Primrose 1300 mg: 1,300 mg of cold-pressed, hexane-free oil from Oenothera biennis seed per softgel (bovine gelatin), typically providing 8-10% GLA, about 104-130 mg; 60 softgels. Take 1 softgel 1 to 2 times daily with food. For adults only.
- Solaray Female Hormone Blend SP-7C: a 910 mg proprietary herbal blend per 2-VegCap serving with black cohosh, dong quai, passion flower, red raspberry leaf, fenugreek, licorice root, cramp bark, chamomile, saw palmetto, wild yam, butternut bark and kelp; 100 VegCaps. Take 2 VegCaps three times daily with a meal or a glass of water. Do not use if pregnant or nursing, or if you have high blood pressure (it contains licorice).
- Solaray Inositol 500 mg: 500 mg of inositol per VegCap, 100 VegCaps; 1 VegCap daily with a meal or a glass of water. PCOS studies mostly used 2-4 g of myo-inositol a day, so this is a much lower dose, and it is not a PCOS or fertility treatment on its own.
Frequently Asked Questions
Does evening primrose oil enlarge the breasts or help weight loss?
There is no evidence for either; these are marketing claims.
Can I apply it to my skin?
It appears in some cosmetics as a moisturiser, but that does not treat eczema. Patch-test a small area first.
Does it interact with the contraceptive pill?
No important interaction is known, but always tell your doctor about everything you take.
How long can I take evening primrose oil?
Studies usually lasted a few months. Reassess after three months, and stop if you see no benefit.
Conclusion
Evening primrose oil is a source of GLA, but its evidence for eczema, PMS, breast pain and hot flashes is weak or mixed. Use evening primrose oil only at the label dose, stop it before surgery, be careful with blood thinners, and never use it to induce labour. Find NOW Super Primrose at No Style Like Pharmacy.
This article was reviewed by the No Style Like pharmacy content team. It is for general awareness only and does not replace advice from your doctor or pharmacist.
Supplements are not a treatment for eczema, breast pain or menstrual disorders, and should not be used in pregnancy without your doctor. For more information see the NCCIH evening primrose oil fact sheet.