Evening Primrose Oil a Mixed Bag for Mastalgia.

CHICAGO -- Evening primrose oil has shown some benefit for women whose most prominent symptom of premenstrual syndrome is mastalgia. Chaste tree berry extract may help women whose periods are irregular or too frequent, Dr. Victoria E. Rand said in a literature review at a conference on alternative and complementary medicine sponsored by the University of Chicago.

* Evening primrose oil. Seeds from the native American wildflower Oenothera biennis L. contain high levels of the essential fatty acids linoleic acid and gammalinolenic acid, which are precursors of the anti-inflammatory prostaglandin [E.sub.1]. "Women with PMS often have low levels of gamma-linolenic acid," said Dr. Rand of the University of California, San Francisco. Several clinical trials of evening primrose oil have been conducted in Europe, but most were methodologically flawed and showed inconsistent results. Efforts to conduct a metaanalysis identified only two well-controlled, randomized studies, neither of which showed any overall benefit from the supplement (Control. Clin. Trials 17[1]:60-68, 1996). Breast pain, however, showed significant improvement in some of the studies, Dr. Rand said, referring in particular to one trial in which evening primrose oil was compared with danazol, bromocriptine, progestins, and placebo for the treatment of mastalgia (Lancet 2[8451]:373-77, 1985).

In this study of 291 women with menstruation-associated breast pain, 70% of the women randomized to receive danazol reported that the drug was effective, compared with 47% of those given bromocriptine and 45% of those given evening primrose oil. Adverse effects, however, were reported by 22% of the women in the danazol group and 33% in the bromocriptine group, compared with only 2% in the primrose oil group.

She also noted that there has been one ...