Flower of Evening Primrose - Oenothera Biennis (Onagraceae).

Medicinal Use of Evening Primrose – Oenothera Biennis (Onagraceae)


Biennial herb growing to 8 in (20 cm). Has red blotches on stem, crinkled lances haped leaves, 4-petaled yellow flowers, and elongated seed capsules.

Habitat & Cultivation

Native to North America, evening primrose is now commonly found in many temperate zones around the world. It thrives in open areas, especially in dunes and sandy soil. Evening primrose is grown commercially for its seed oil.

Parts Used

Leaves, stem bark, flowers, seed oil.


Evening primrose oil is rich in essential fatty acids—linoleic (about 70%) and gammalinolenic acid (about 9%) in particular. Its action mostly depends on the gammalinolenic acid (GLA), which is a precursor of prostaglandin E1. The oil is often combined with vitamin E to prevent oxidation.

Medicinal Actions & Uses

The flowers, leaves, and stem bark of evening primrose have astringent and sedative properties. All three parts have been employed in the treatment of whooping cough. Evening primrose has also been taken for digestive problems and asthma, and used as a poultice to ease the discomfort of rheumatic disorders.

The oil, applied externally, is beneficial in the treatment of eczema, certain other itchy skin conditions, and breast tenderness. Taken internally, the oil has an effect in lowering blood pressure, and in preventing the clumping of platelets. The oil is now commonly taken for premenstrual problems, including tension and abdominal bloating, and may prove helpful in conditions as diverse as dry eyes and multiple sclerosis.


Do not take evening primrose oil if suffering from epilepsy.