Evening Primrose (Oenothera Biennis)

Medical Uses

Evening primrose is used for circulation problems caused by diabetes, for symptoms of premenstrual syndrome, and for benign breast pain. It may be beneficial in rheumatic conditions and atopic eczema.

Historical Uses

In the past, evening primrose has been used to treat female complaints, skin problems, and respiratory difficulties.

Growth

Evening primrose is a biennial North American plant with a beautiful, fragrant yellow flower that opens in the evening. It prefers sun and dry soil. The seeds are pressed into oil.

Evening Primrose: Part Used

• Seed, pressed into oil

Major Chemical Compound

• Gamma-linolenic acid (GLA)

Evening Primrose: Clinical Uses

Evening primrose is used for diabetic neuropathy, symptoms of premenstrual syndrome, and benign breast pain. It may be beneficial in rheumatic conditions and atopic eczema. In a survey of certified nursing midwives who used herbal preparations, 60 percent stated that they used evening primrose oil to stimulate labor.

Mechanism of Action

GLA is an essential fatty acid. These acids are essential for keeping cells healthy and for preventing cardiovascular disease, depression, infections, sterility, cancer, and dry hair and skin. Anti-inflammatory properties maybe a result of mediation by prostaglandin E1.Evening primrose oil also helps to counter neuropathy by enhancing peripheral blood flow.

Evening Primrose: Dosage

Evening primrose oil is standardized to contain 7 to 10 percent GLA.

Capsules: 1 to 2 capsules three times daily for premenstrual syndrome, 8 to 12 capsules daily (containing 320-480 mg of total GLA) for diabetic neuropathy, and 6 capsules daily for eczema. Take with meals. It may be several months before an effect is evident.

Side Effects

Evening primrose may cause minor stomach upset, nausea, or headache at high doses.

Contraindications

• None are known.

Herb-Drug Interactions

Evening primrose should not be taken with phenothiazines. It may decrease the seizure threshold.

Pregnancy and Breast-Feeding

This herb is safe for pregnant and breast-feeding women when consumed appropriately.

Summary of Studies

Keen, H, et al. (1993). This randomized, double-blind, placebo-controlled study included 84 patients with diabetes and neuropathy who took 12 capsules (480 mg of total GLA) over 1 year. Results: Neurological improvements were statistically significant.

Ford et al. (2001). A 2-week treatment with evening primrose oil showed improvement in blood flow and nerve function in diabetic rats.

Fukushima et al. (2001). Omega-6 and -3 fatty acids, including evening primrose oil, inhibited the increase of serum cholesterol in rats fed a diet with increased cholesterol.

Evening Primrose: Warnings

Evening primrose may cause minor stomach upset, nausea, and headache in large dosages.

• Report side effects to your health-care practitioner.

• Don’t take evening primrose with any anti-nausea medications.

Evening primrose is safe for pregnant and breast-feeding women when consumed appropriately.