Information on Evening Primrose

Latin NameOenothera biennis
Part UsedSeed Oil
Herb FormsCapsule.
AffectsBlood, Immune system
CautionsNone noted.
Botanical InfoA tall biennial weed with large yellow flowers in the Evening Primrose family, turning into short spike-like capsules that produce numerous small brown seeds.
DescriptionEvening primrose oil is used quite successfully for psoriasis and eczema. It is widely used for PMS and arthritis, though the studies are less convincing for these two uses. It is often effective for reducing breast tenderness associated with the menstrual cycle. Other uses, which include lowering serum cholesterol and reducing hyperactivity in children, are not fully substantiated. The oil is rich in essential fatty acids, including GLA (gamma linolenic acid), which is an intermediary in prostaglandin synthesis. Prostaglandins are local-acting hormone-like substances that control inflammation among other functions.

Evening Primrose has a taste of BITTER and a temperature of COOL.


Capsules250 to 500 mg daily

Ailments Treated by Evening Primrose

AilmentTreatment SupportApplication
PMS [Premenstrual Syndrome]anti-inflammatorycapsule
Breasts, soreprostaglanding-blockeroil in capsules
Eczemaprostaglanding-inhibitoroil in capsules


Newall, C. et al.. 1996. Herbal Medicines: A Guide for Health-care Professionals. London: The Pharmaceutical Press.
Leung, A. and S. Foster. 1996. Encyclopedia of Common Natural Ingredients. New York: J. Wiley & Sons.
McGuffin, M. et al. 1997. Botanical Safety Handbook. Boca Raton: CRC Press.
Felter, H.W. and J.U. Lloyd. 1983. (1898). King's Dispensatory. Portland, OR: Eclectic Medical Publications.
Weiss, R. 1988. Herbal Medicine. Beaconsfield, England: Beaconsfield Publishers.
Wren, R.C. 1988. Potter's New Cyclopaedia of Botanical Drugs. Essex: C.W. Daniel Co. Ltd.
Reynolds, J., ed. 1993. Martindale, The Extra Pharmacopoeia. London: The Pharmaceutical Press.