Evening primrose (Oenothera biennis) is a herb that’s native to Europe and North America. Evening primrose oil is the oil from the seed of the evening primrose plant. Evening Primrose Oil (EPO) contains a high concentration of a fatty acid called gamma-linolenic acid (GLA) and it is this fatty acid that is largely responsible for the healing effects of the plant. (EPO contains 2–15% GLA and 70% linolenic acid, which are types of polyunsaturated omega-6 essential fatty acids). In addition to evening primrose oil, gamma-linolenic acid is found in black currant oil and borage oil.
Evening Primrose Oil Medicinal Uses
Evening primrose oil (EPO) is used usually to relieve the itchiness causes by certain skin problems, such as eczema and dermatitis. A study of 1,207 participants found that evening primrose oil helped alleviate symptoms from skin conditions, including itching, crusting, edema and redness.
PMS and Mastalgia
Women use EPO for premenstrual syndrome, breast pain, endometriosis, and symptoms of menopause such as hot flashes. Women with premenstrual syndrome may have impaired conversion of linoleic acid to GLA. Some studies have showed that supplementing with GLA in the form of evening primrose oil has a important effect on the symptoms of premenstrual syndrome (PMS). GLA relieves premenstrual breast pain and tenderness and other premenstrual syndrome symptoms including painful periods, headaches, irritability and bloating,
In Helsinki, in a clinical study, participants were treated with Efamol (primrose oil as a source of gammalinolenic acid) for four cycles. These participants had not been treated with drugs before the experiment. Efamol demonstrated a 40% average improvement in parameters tested, particularly in irritability and depression. A study at St. Thomas Hospital in London found that when PMS suffers were given EPO three times daily, 67% of the participants were symptom-free and 22% achieved partial relief. In open studies performed at the Cardiff Mastalgia Clinic, Evening Primrose Oil has been found to produce favorable effects in 44% of women with cyclical mastalgia. Evening primrose oil is licensed for the treatment of breast pain (mastalgia) in the United Kingdom.
Diabetic neuropathy is a type of nerve damage that can occur if you have diabetes. Studies have discovered that evening primrose oil could help safeguard individuals from diabetic neuropathy. A review of 3 randomized, controlled studies showed EPO might improve symptoms of diabetic neuropathy. Supplementing with 4 grams of EPO per day for 6 months has been found in double-blind research to improve nerve function and to relieve pain symptoms of diabetic neuropathy
Some studies suggest that supplements that contain GLA, including evening primrose oil, may be of benefit to individuals with rheumatoid arthritis. A study was carried out for 24 weeks with 37 arthritis patients treated with 1.4 g/day GLA or placebo. Joint tenderness and swelling, morning stiffness, grip strength, and ability to perform daily activities were examined. Treatment with GLA reduced the signs and symptoms of the disease significantly in all four parameters, while patients receiving placebo had no significant improvement. Arthritis Research UK4 reported that a clinical study involving 49 patients found that 94% of patients who got primrose oil alone and 93% who received primrose oil combined with fish oil reported a significant improvement of disease-related symptoms, including pain and morning stiffness, compared to just 30% in the placebo group. Evening primrose oil was also significantly effective in reducing the use of non-steroidal anti-inflammatory drugs (NSAIDs) during the trial period.
Studies have used 2 – 8 grams of EPO daily. The typical content of gamma-linolenic acid (GLA) in the oil is 8% to 10%. Being a fatty acid, it is best taken with meals to enhance digestion and absorption. Evening primrose oil products should be stored out of direct sunlight in light-resistant containers in a refrigerator to prevent rancidity.
EPO may lower the seizure threshold and precipitate seizures in individuals taking phenothiazines. The use of evening primrose oil during pregnancy is not supported in the literature.