Evening Primrose Oil

Health Tips / Evening Primrose Oil

What Is It?

Evening primrose oil is extracted from the evening primrose plant (Oenothera biennis), a wildflower found in North America, Europe and parts of Asia. The plant’s pale yellow flowers open in the evening–hence its common name–and its seeds bear the special fatty oil that is used in healing today.

In another era, Native Americans and the early settlers gathered the plant and its root to treat such ailments as hemorrhoids, stomachaches, sore throat, and bruises. It took modern research to unveil the therapeutic power contained within the seed oil: an essential fatty acid (EFA) called gamma-linolenic acid (GLA). Once processed in the body, GLA, an omega-6 fatty acid, exerts anti-inflammatory and other healing actions.

Evening primrose oil is certainly not the only source of GLA; various foods actually contain small amounts of it and the body produces GLA on its own from a number of dietary fats. But evening primrose oil offers an unusually concentrated source, with 7% to 10% of its fatty acids available in the form of GLA. Interestingly, borage oil features even more GLA (20% to 26%), and black currant oil offers rich stores as well (14% to 19%), but their effectiveness and safety for many ailments has not been as intensively examined as evening primrose oil. Nonetheless, some people prefer borage and black currant oils because they require a lower dose (at less total cost) for the same amount of GLA.

Health Benefits

The remarkably rich stores of GLA in evening primrose oil are what make it so valuable in healing. Taken internally, the body converts GLA into prostaglandins. These hormonelike compounds help regulate various body functions, controlling inflammation in some cases and promoting it in others. The prostaglandins produced from GLA fall into the anti-inflammatory category. Cell membranes also rely on the presence of GLA.

Specifically, evening primrose oil may help to:

Relieve the discomforts of PMS (premenstrual syndrome), menstruation, endometriosis and fibrocystic breasts. By interfering with the production of inflammatory prostaglandins released during menstruation, the GLA in evening primrose oil can help to lessen menstrual cramps. It may also minimize premenstrual breast tenderness, irritable bowel flare-ups, and carbohydrate cravings, and help to control endometriosis-associated inflammation. Many PMS sufferers are found to have unusually low levels of GLA in their systems, which is why supplements might help so much. Although the oil has not been widely used in this country for treating PMS, Europeans have long used it for this condition. In women with fibrocystic breasts, the oil’s essential fatty acids can minimize breast inflammation and promote the absorption of iodine, a mineral that can be present in abnormally low levels in women with this condition.

Ease the joint pain and swelling of rheumatoid arthritis. Supplementation with evening primrose oil and other sources of GLA has been shown to lessen the joint pain and swelling of this crippling disease. A six-month study reported fewer signs of inflammation in rheumatoid arthritis sufferers taking capsules containing GLA than in those taking a placebo. In another trial, the number of tender joints and swollen joints dropped significantly with GLA but not with a placebo.

Prevent diabetes-associated nerve damage. Research indicates that the GLA in evening primrose oil can help prevent–and in some cases even reverse–the nerve damage (neuropathy) so commonly seen with diabetes. In a year-long study, such symptoms as numbness, tingling, and loss of sensation in participants with mild diabetic neuropathy were less marked in those who took evening primrose oil than in those who took a placebo.

Reduce the symptoms of eczema. In some cases, eczema develops when the body has problems converting dietary fats into GLA. Getting supplemental GLA from evening primrose oil may therefore be helpful. Some studies indicate that this oil can outperform a placebo in relieving eczema-related inflammation, as well as the itching, oozing, and flaking associated with this condition. By taking GLA, eczema sufferers may tolerate reduced doses of steroid creams and drugs–many of which cause unpleasant side effects. Not all studies point to such benefits, however, and many conventional doctors remain skeptical.

Help treat acne and rosacea. By working to dilute sebum, a thick oily substance that is oversecreted in some people with acne, the essential fatty acids in evening primrose oil may reduce the risk of pores becoming clogged and lesions developing. The oil’s EFAs help treat rosacea by reducing inflammation, controlling cells’ use of nutrients, and by producing prostaglandins, which stimulate the contraction of blood vessels.

Alleviate inflammation associated with lupus. Inflammation in the kidneys, joints, skin, and other areas of the body caused by this condition may subside as a result of evening primrose oil’s anti-inflammatory actions. Taking the oil may lower elevated cholesterol levels in those suffering from lupus as well.

Lessen numbness and tingling. By helping to keep the myelin sheaths that cover nerve fibers healthy–and communication between the brain and nerve cells functioning smoothly–the essential fatty acids in evening primrose oil may help to reduce or prevent numbness and tingling in the feet, hands or legs.

Combat damage from multiple sclerosis. The abundant supply of essential fatty acids in evening primrose oil may be valuable in minimizing the inflammation associated with this progressive nerve disorder. The fatty acids may also contribute to healthy nerve development when taken over time. It is important to initiate supplement use as soon as possible after diagnosis.

Treat Alzheimer’s-related memory deficiencies. By boosting the transmission of nerve impulses, evening primrose oil may be valuable in treating this progressive brain disorder.

Protect against the effects of aging. As the body ages, it loses its ability to convert dietary fats into GLA. Because this essential fatty acid is involved in so many body processes, taking evening primrose oil can help to compensate for any deficiencies in GLA.

Counter impotence and female infertility. By promoting blood flow, the GLA in evening primrose oil can help treat a primary cause of male impotence–compromised circulation leading to impaired penile blood flow. The oil is often taken with vitamin C and ginkgo biloba for this purpose. In addition, when the oil is taken long term, GLA can help prevent blood vessel narrowing, often a consequence of plaque buildup from high cholesterol. By improving uterine function, GLA may also help those who are unable to conceive.

Alleviate Raynaud’s disease symptoms. One study found a benefit in gently rubbing evening primrose oil directly into fingertips numbed by this circulatory disorder. The oil’s GLA content is thought to be responsible for the improvement. The toes may benefit from this treatment as well, although the oil’s effect on toes was not examined in the study.

Nourish nails, scalp, and hair. The rich stores of essential fatty acids in evening primrose oil not only prevent nails from cracking but also help to keep them generally healthy. In addition, the essential fatty acids nourish the scalp, making the supplement potentially valuable in treating a variety of hair problems.

Prevent alcohol withdrawal symptoms. GLA prompts the brain to produce a specific type of prostaglandin called prostaglandin E, which works to prevent withdrawal symptoms such as depression and seizures by indirectly protecting the liver and nervous system. Note: Evening primrose oil has also been found to be useful for a number of other disorders. For information on these additional ailments, see our Dosage Recommendations Chart for Evening Primrose Oil.



Dosage Information

Special tip:

–Equivalent amounts of GLA (240 mg a day) can be obtained from daily dosages of 1,000 mg of borage oil or 1,500 mg of black currant oil.

For most of the ailments mentioned: Take 1,000 mg evening primrose oil three times a day. This provides 240 mg of GLA over the course of a day.

For diabetes: Take 1,000 mg evening primrose oil three times a day, along with 1,000 mg of fish oils twice a day.

For Raynaud’s disease: Massage the oil from one or two opened capsules into the fingertips or toes. Or take 1,000 mg evening primrose oil three times a day. Be sure to check out our Dosage Recommendations Chart for Evening Primrose Oil, which lists therapeutic dosages for specific ailments at a glance.

Guidelines for Use

By taking evening primrose oil (or other GLA sources) with food, you will not only help ensure good absorption of GLA but possibly minimize any unpleasant side effects.

Be sure to buy evening primrose oil from a reliable manufacturer; cheap substitutes such as soy and safflower oils have been found in some commercial products.

Particularly when treating PMS and related discomforts, it’s important to ensure proper conversion of evening primrose oil into GLA by taking it with a high-quality multimineral (it should contain zinc, vitamin C, vitamin B-complex vitamins and magnesium).

A small amount of vitamin E added to evening primrose oil products reportedly slows the rather rapid breakdown of important fatty acids; opt for vitamin E-enhanced products when possible.

It may take two to six months to see effects for skin, hair and nail problems.

General Interaction

Evening primrose oil may increase the risk of temporal lobe epilepsy in schizophrenic patients taking phenothiazine epileptogenic drugs.

There are no other known drug or nutrient interactions associated with evening primrose oil or its contained essential fatty acids. Note: For information on interactions with specific generic drugs, see our WholeHealth Chicago Drug/Nutrient Interactions Chart.

Possible Side Effects

Bloating or abdominal upset develop in a small percentage (about 2%) of those participating in evening primrose oil studies.


Data to support the safety of long-term use of evening primrose oil are not available. There have been few or no reports of toxic reactions to evening primrose oil over nearly two decades of widespread use as a supplement, however.


Acne 1,300 mg twice a day
Aging 1,000 mg 3 times a day
Alcoholism 1,000 mg 3 times a day
Alzheimer’s Disease 1,300 mg twice a day
Diabetes 1,000 mg 3 times a day
Eczema 1,300 mg twice a day
Endometriosis 1,300 mg twice a day
Fibrocystic Breast Changes 1,300 mg twice a day
Hair Problems 1,300 mg twice a day
Impotence 1,300 mg twice a day
Infertility, Female 1,300 mg twice a day
Lupus 1,300 mg twice a day
Multiple Sclerosis 1,300 mg twice a day
Perimenopause 1,300 mg twice a day; use as alternative to borage oil PMS 1,000 mg 3 times a day
Psoriasis 1,300 mg twice a day

Raynaud’s disease 1,300 mg in capsules twice a day. As alternative to borage oil, apply primrose oil to the affected portion of skin every day.

Rosacea 1,300 mg twice a day

Doctor Recommendations
David Edelberg, M.D.

With pale yellow flowers that open at dusk, the poetically named evening primrose flower (Oenothera biennis) was long used in traditional healing by Native Americans and early settlers. Today, it’s the special fatty acid extracted from its seed oil that attracts all the attention–and rightly so. The oil boasts high concentrations of gamma linolenic acid (GLA), an omega-6 essential fatty acid. The body converts GLA into prostaglandins, hormonelike compounds that fight inflammation and help the body to heal.


Many women entering perimenopause suffer from lingering menstrual discomforts such as breast tenderness, irritability, bloating, and cramping. Some complain of heavy or scant flow and generally irregular periods. Evening primrose oil, with its high concentrations of GLA, may ease these discomforts by fighting inflammation and stabilizing hormonal shifts.


Other GLA sources, such as borage oil and black currant oil, will work equally well. They even contain more GLA: Evening primrose oil has only 7% to 10% GLA, while borage oil offers 20% to 26% and black currant oil 14% to 19%. On the other hand, evening primrose oil has been the most intensively studied for safety and effectiveness.


Evening primrose oil comes in various forms, including: Softgel capsules and liquids to be taken orally. The capsules can even be opened to release the oil, which you can then directly apply to the affected area. Cream to be rubbed directly onto an area of dry skin or other skin irritation. Shopping tip: Not long ago, evening primrose oil was the most expensive source of GLA, but the price has dropped recently. Look for products enhanced with vitamin E, which reportedly slows down GLA breakdown. Stick with a manufacturer whose products you trust; cheap substitutes such as soy and safflower oils have been found in some commercial products.


Take evening primrose oil with food to prevent side effects and boost absorption.

Be well,
David Edelberg, MD