Penn Herb Wellness Guide
Evening Primrose OilFind Products
Evening primrose oil (EPO), comes from the seeds of the evening primrose plant. Like black currant seed oil and borage oil, EPO contains gamma linolenic acid (GLA), a fatty acid that the body converts to a hormone-like substance called prostaglandin E1 (PGE1).
- Reliable and relatively consistent scientific data showing a substantial health benefit.
- Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
- For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement,little scientific support.
Our proprietary “Star-Rating” system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by the medical community, and whether studies have found them to be effective for other people.
For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.
This supplement has been used in connection with the following health conditions:
| Used for | Amount | Why |
|---|---|---|
Eczema | Adults: 500 to 1,000 mg a day of GLA; children: proportionately less, according to body weight |  [2 stars] Supplementing with evening primrose oil can supply anti-inflammatory fatty acids that are missing in many people with eczema. |
Fibrocystic Breast Disease | 3 grams daily | [2 stars] Taking evening primrose oil may help alleviate symptoms. |
Osteoporosis (Fish Oil) | 6 grams daily | [2 stars] Fish oil combined with evening primrose oil (EPO) may improve calcium absorption and promote bone formation. |
Premenstrual Syndrome | 3 to 4 grams daily | [2 stars] Women with PMS may have impaired conversion of linoleic acid to gamma linolenic acid (GLA). Evening primrose oil contains GLA and may reduce PMS symptoms. |
Rheumatoid Arthritis | 540 to 1,100 mg daily of GLA | [2 stars] Evening primrose oil appears to be an effective treatment for people with rheumatoid arthritis. It contains gamma linolenic acid, which is converted in part to an anti-inflammatory substance. |
Skin Ulcers | 1,500 mg with each meal | [2 stars] A preliminary report suggested that evening primrose oil improves blood flow to the legs and heals or reduces the size of venous leg ulcers. |
Alcohol Withdrawal | Refer to label instructions |  [1 star] In a double-blind study of alcoholics in a detox program, supplementing with EPO led to greater improvement than did placebo in some parameters of liver function. |
Atherosclerosis | Refer to label instructions | [1 star] Taking evening primrose oil has been shown to lower cholesterol in double-blind research. Lowering cholesterol levels should in turn reduce the risk of atherosclerosis. |
Attention DeficitHyperactivity Disorder | Refer to label instructions | [1 star] A deficiency of several essential fatty acids has been observed in some children with ADHD. In one study, children who received evening primrose oil showed minor improvements. |
Chronic Obstructive Pulmonary Disease | Refer to label instructions | [1 star] Evening primrose oil contains gamma-linolenic acid, a type of omega-3 fatty acid that has been linked to reduced risk of COPD. |
Intermittent Claudication | Refer to label instructions | [1 star] In a preliminary trial, supplementing with evening primrose oil led to a 10% increase in exercise tolerance in people with intermittent claudication. |
Irritable Bowel Syndrome and PMS | Refer to label instructions | [1 star] In one trial, women with IBS who experienced worsening symptoms before and during their menstrual period were helped by taking evening primrose oil. |
Multiple Sclerosis | Refer to label instructions | [1 star] The omega-6 fatty acids found in such oils as evening primrose oil (EPO) may be beneficial. When people with MS were given EPO, their hand grip improved in one study. |
Raynaud’s Disease | Refer to label instructions | [1 star] Fatty acids in evening primrose oil (EPO) inhibit the formation of prostaglandins, which promote blood vessel constriction. One study found that supplementing with EPO reduced the number and severity of attacks. |
Scleroderma | Refer to label instructions | [1 star] People with scleroderma can have a metabolic block that interferes with the body’s ability to make GLA, the main constituent of evening primrose oil. In preliminary research, supplementing with EPO has helped people with several skin conditions. |
Sjogren’s Syndrome | Refer to label instructions | [1 star] People with Sjogren’s syndrome can have a metabolic block that interferes with the body’s ability to make GLA, the main constituent of evening primrose oil. In preliminary research, supplementing with EPO has helped people with several skin conditions. |
Tardive Dyskinesia | Refer to label instructions | [1 star] Several people have experienced improvement while taking evening primrose oil. |
Type 1 Diabetes | Refer to label instructions | [1 star] Evening primrose oil may relieve nerve pain in those with type 1 diabetes. |
Type 2 Diabetes | 4 grams daily | [1 star] Preliminary research suggests evening primrose oil may be helpful for preventing and treating diabetic neuropathy. |
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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.