Health Benefits of Evening Primrose Oil

Evening primrose oil is a supplement that has been used for hundreds of years. The oil comes from the seeds of evening primrose (Oenothera biennis). 

Evening primrose is a plant native to North and South America that now also grows in Europe and parts of Asia. The plant blooms from June to September, producing large, yellow flowers that only open in the evening.

The oil that comes from evening primrose’s seeds has omega-6 fatty acids. Evening primrose oil is used for a variety of reasons, including in the management of eczema and menopause. Evening primrose oil is also referred to as king’s cure-all and EPO.

Benefits of Evening Primrose Oil

Evening primrose oil is rich in health-promoting compounds such as polyphenols and the omega-6 fatty acids gamma-linolenic acid (9%) and linoleic acid (70%).

These two acids help many of the body’s tissues to function properly. They also have anti-inflammatory properties, which is why evening primrose oil supplements may be helpful in improving symptoms related to inflammatory conditions like eczema.

May Relieve Eczema Symptoms

Taking evening primrose oil supplements may help relieve certain symptoms of inflammatory skin conditions like atopic dermatitis, a type of eczema. 

One study in Korea of 50 people with mild atopic dermatitis found that people who took evening primrose oil capsules for four months had significant improvements in eczema symptom severity. Each capsule contained 450mg of the oil, with children 2 to 12 years taking four a day and everyone else taking eight a day. The participants also had slight improvements in skin hydration.

It’s thought that the fatty acids found in evening primrose oil help restore certain anti-inflammatory substances, including prostaglandin E1, that tend to be low in people with eczema.

However, not all studies have found evening primrose oil to be helpful for eczema symptoms. More research, with larger sample sizes, is needed to determine whether evening primrose oil is a worthwhile natural treatment for people with eczema.

Could Help Minimize Tretinoin Side Effects 

Tretinoin is a medication often used to treat severe forms of acne. It is sold under several brand names, including Altreno and Atralin. Although tretinoin can be effective for reducing acne symptoms, it can lead to side effects like dry skin.

A 2022 study that included 50 people with acne found that when the participants were treated with a combination of oral isotretinoin and 2,040mg of evening primrose oil for nine months, their skin hydration significantly increased. This helped reduce symptoms like dryness, cracked lips, and peeling skin.

Participants who were treated with isotretinoin only experienced significant decreases in skin hydration.  

The fatty acids like gamma-linolenic acid and linoleic acid found in evening primrose oil may help counteract the skin-drying effects of isotretinoin because they work to prevent excessive water loss from the skin and maintain skin hydration.

May Improve Some Menopause Symptoms  

Menopause is the time when you haven’t had a period for 12 months. It’s caused by a natural decrease in reproductive hormones like estrogen and usually occurs between the ages of 45 and 55.

Menopause usually causes a variety of symptoms, including hot flashes and night sweats.

Evening primrose oil is a source of phytoestrogens, or compounds that mimic the effects of estrogen in the body. Because it contains phytoestrogens, evening primrose oil may be helpful for reducing menopause symptoms related to low estrogen. 

A study in 170 women who’d reached menopause found that those who supplemented with 2,000mg of evening primrose oil daily for eight weeks experienced significant reductions in the frequency and severity of night sweats compared to a placebo group.

Other studies have shown that evening primrose oil supplements may be helpful for menopause symptoms like hot flashes and mood changes.

While these results are encouraging, more research is needed to confirm the potential benefits of evening primrose oil supplements for menopause symptoms.

May Improve PMS Symptoms

Premenstrual syndrome (PMS) is a group of symptoms people might get in the week or two leading up to their period. Symptoms can include anxiety, depression, acne, fatigue, and headache.

Evening primrose oil has been shown to reduce PMS symptoms. For one study, 80 women with PMS received 1.5g of evening primrose oil or placebo for three months. After the three months, those who had taken the oil reported significantly less severe symptoms than those who had taken the placebo.

It’s believed that the linoleic acid in evening primrose oil could be behind this effect, linoleic acid is known to alleviate PMS symptoms.

May Minimize Breast Pain

Breast pain, or mastalgia, might happen as your hormones change during your menstrual cycle. While some results looking into the connection have been mixed, most studies have shown that taking evening primrose oil may help in reducing this pain. The dosage and length of supplementation ranged throughout the different studies.

It is known that linoleic acid deficiency makes the breast tissues sensitive to sex hormones, which is associated with breast pain. Evening primrose oil is rich in this type of acid.

May Help Improve Lipid Levels

A review of six studies found that taking four grams or less of evening primrose oil per day significantly reduced triglyceride levels in people with high cholesterol. Triglycerides are a type of fat (lipid) in your blood that can raise your risk of heart disease if levels are too high.

The same review found that evening primrose oil could also help boost levels of “good” HDL cholesterol. HDL, or high-density lipoprotein, helps remove cholesterol from your arteries.

Larger studies—that use higher doses and that last longer—are needed to say for certain what effect evening primrose oil has on lipid profile.

May Improve Rheumatoid Arthritis Symptoms

One older review of past studies showed that supplements containing gamma-linolenic acid, including evening primrose oil, may be helpful for improving rheumatoid arthritis symptoms like joint pain. Still, there is not enough research to say for sure.

May Help Reduce Diabetic Neuropathy Pain

Some findings suggest that taking evening primrose oil supplements could help reduce pain associated with diabetic neuropathy, which is nerve damage caused by high blood sugar.

For the study, a small group of people with diabetic neuropathy took four 450mg-capsules of evening primrose oil twice a day—four 30 minutes before breakfast and four 30 minutes before dinner—for 12 weeks.

This is thought to be due to the gamma-linolenic acid evening primrose oil has.

How to Take Evening Primrose Oil

Evening primrose oil can be taken during the day or at night and is usually taken in divided doses. The directions might instruct you to take the supplement with a meal. 

Evening primrose oil is available as capsules, softgels, and liquids. It can also be applied topically and can be found in lotions, creams, and patches.

Dosage 

Evening primrose dosing recommendations vary, but the supplement is typically used in doses of 2-6 grams a day for three to 12 months.

If you have questions about evening primrose oil dosing, reach out to your healthcare provider for advice. 

Is Evening Primrose Oil Safe?

Evening primrose oil, in both its topical and oral form, is considered safe for adults. In oral form, it has been shown to be safe at up to 6 grams a day for up to a year.

When taken in its oral form, the oil may even be safe for people who are breastfeeding or pregnant, as well as children. Since less research has been done in these populations, it is best that these groups use caution if taking the supplement.

Potential Drug Interactions

Evening primrose oil may interact with more than 200 medications. Most of these interactions are mild, such as headache or gastrointestinal effects.

Some interactions may be more concerning. Taking evening primrose oil with the following medications could result in adverse effects:

• Blood thinners: Taking evening primrose oil with anticoagulants and antiplatelets, which prevent blood clots from forming, could increase the risk of bleeding.
• Lithium: Taking evening primrose oil with lithium, which is used in the management of bipolar disorder, might decrease lithium levels and effects.
• Kaletra (lopinavir/ritonavir): The effects of this combination medicine for HIV may increase when taken alongside evening primrose oil.
• Phenothiazines: Your risk of seizure might increase if you take evening primrose oil supplement with medications in this class of antipsychotics.

If you’re taking any medications, talk with your healthcare provider first. 

What to Look For

When shopping for an evening primrose oil, it’s important to purchase a high-quality supplement from a trusted company. 

Many supplement companies—such as those certified by organizations like NSF, UL, and USP—use third-party labs to test their products for quality and purity. This helps ensure supplements are free from harmful adulterants and contain appropriate forms and doses of ingredients. 

You’ll also want to consider your budget. Evening primrose supplements are available at different price points. Shop around until you find an evening primrose supplement that fits within your budget.  

Can You Take Too Much Evening Primrose?

Evening primrose oil is safe for most people to take, even at higher doses of six grams. 

However, it is possible to overdo it when it comes to any supplement, including evening primrose oil. Talk with a healthcare provider to find out what your limit should be.

Side Effects of Evening Primrose Oil

Evening primrose oil supplements aren’t associated with many serious side effects, but they may cause mild reactions.

Gastrointestinal-related side effects from evening primrose oil can include:

• Abdominal pain
• Diarrhea
• Indigestion (fullness or general discomfort in your abdomen)
• Gas
• Nausea
• Vomiting 

These side effects will usually go away with continued use of the supplement.

Other potential side effects include:

• Headache
• Dizziness 
• Skin rash
• Acne

Evening primrose oil might also have negative effects relating to blood, potentially decreasing platelet aggregation (how well platelets can clump to one another) and prolonging bleeding time. However, such an adverse effect is rare. Evening primrose is usually well-tolerated. 

A Quick Review

Evening primrose oil is derived from the seeds of the evening primrose plant. The seed oil is rich in beneficial compounds like omega-6 fatty acids, specifically gamma-linolenic acid and linoleic acid.

When taken as a supplement, evening primrose oil may help reduce side effects related to the medication tretinoin and may ease some menopause symptoms. It could also be helpful for certain health conditions like eczema, diabetic retinopathy, and PMS. 

If you’re interested in trying out evening primrose oil, be sure to clear it with your healthcare provider first. Even though it’s not associated with many dangerous side effects, it’s known to interfere with a number of medications and may not be a safe choice for everyone.