Sanmark's organic evening primrose oil is obtained from the seeds of Oenothera Biennis L. by cold expression and filtration only. The oil contains gamma-linolenic acid (GLA), an Omega-6 fatty acid that has both anti-inflammatory and analgesic (pain-relieving) properties. Sanmark's Evening Primrose Capsules are used for premenstrual syndrome (PMS), symptoms of menopause, arthritis, swelling, and other conditions, but there is no good scientific evidence to support its use. In foods, Sanmark's Evening Primrose Capsules are used as a source of essential fatty acids. In manufacturing, Sanmark's Evening Primrose Capsules is used in soaps and cosmetics.