Scientific name: Biennis oenothera 

Common names:

Ayurvedic names:

Chinese names:

Bangladesh names:

Arabic names:    الأخدرية (al akhdhariyyah)

Rain Forest names:

Family: Onagraceae (willow)

Approximate number of species known: 

Common parts used: Seed, seed oil, leaf, bark

Collection: Late spring to late summer

Annual/Perennial: Annual, biennial

Height: 30 to 150cm

Actions:  Anti-inflammatory, anti-allergic, hypotensive

Known Constituents: Essential Oils including linoleic acid (65%), gamma-linolenic acid (8-10%), Triacylglyerols including trilinolein (linoleic acid   dilinoleoyl-mono-gamma-linolenin (two linoleic acids, one GLA)

Constituents Explained:


It has large leaves and yellow flowers.

Traditional Use:

Sometimes used as a supplement for the skin, and for premenstrual syndome (PMS) sypmtoms.

The seed oil is high in Omega 6.  The seeds have been used as a coffeee substitute.

It has been used in inflammation in the joints and muscles.  The leaf and the bark have been used for the liver, 

Grows best in wasteland on sandy soil.

May act as a blood thinner.

Clinical Studies:

A study evaluated the effectiveness of vitamin E, evening primrose oil (EPO), and the combination of vitamin E and EPO for pain control in women with cyclical mastalgia.

A double-blind, randomized, placebo-controlled trial was conducted at two U.S. academic medical centers. Eighty-five women with premenstrual cyclical breast discomfort were enrolled.

Participants were randomly assigned to one of four six-month oral treatments: vitamin E (1,200 IU per day), EPO (3,000 mg per day), vitamin E (1,200 IU per day) plus EPO (3,000 mg per day), or double placebo. The primary outcome measure was change in breast pain, measured by the modified McGill Pain Questionnaire at enrollment and at six months. 

Forty-one patients completed the study. Intent-to-treat analysis (pretesting and post testing) showed a difference in worst-pain improvement with the treatments EPO, vitamin E, and EPO plus vitamin E, but no difference with placebo.

Results from two-sample t-test showed a nonsignificant decrease in cyclical mastalgia individually for the three treatment groups compared with the placebo group. 

Daily doses of 1,200 IU vitamin E, 3,000 mg EPO, or vitamin E and EPO in combination at these same dosages taken for six months may decrease the severity of cyclical mastalgia.

Atopic dermatitis (AD) is a chronic, relapsing, itchy dermatosis of multifactorial origin, which commonly starts in childhood. Defective metabolism of essential fatty acids leading to relative dominance of pro-inflammatory prostaglandins (PGE2 and PGF2) has been reported as an important factor in the pathogenesis of AD. 

A study evaluated the efficacy and safety of EPO in atopic dermatitis in our patients. Consecutive new out-patient department (OPD) patients of a referral hospital in Kolkata clinically diagnosed as having AD were randomly allocated to two groups. 

To the first group, evening primrose oil was supplied as 500-mg oval clear unmarked capsules, while placebo capsules identical in appearance and containing 300 mg of sunflower oil were given to the other group. 

Treatment continued for a period of 5 months. With pre-designed scoring system (based on four major parameters: extent, intensity, itching, and dryness), clinical evaluation was done at baseline and subsequent monthly visits. Data of the first 25 patients from each group who completed the 5 months of trial were compiled and analyzed.

At the end of the fifth month, 24 (96%) patients of EPO group and 8 (32%) patients of placebo group showed improvement. There was significant difference in outcome of treatment between two groups. 

No significant adverse effect was reported by any patient/guardian at any point of assessment. Evening primrose oil is a safe and effective medicine in management of AD.


Pruthi S, Wahner-Roedler DL, Torkelson CJ, Cha SS, Thickle SL, Hazelton JH, Bauer BA. “Vitamin E And Evening Primrose For Management Of Cyclical Mastalgia: A Randomized Pilot Study.” 2010 April

Senapati S, Banerjee S, Gangopadhyay DN. “Evening Primrose Oil Is Effective In Atopic Dermatitis: A Randomized, Placebo-Controlled Trial.” 2008 September-October