The researchers analysed the benefits and side effects associated with evening primrose oil and borage oil in 27 studies involving a total of 1,596 people (adults and children) in 27 countries. Participants took evening primrose oil or borage oil, or a placebo, for between 3-24 weeks. Overall, the researchers found that taking evening primrose or borage oil offered no clear improvement of eczema symptoms over placebos. Commonly used placebos included olive oil and paraffin oil. There was also no improvement in quality of life with the complementary therapies, although only two studies considered this measure.
"There is no evidence that taking either evening primrose or borage oil is of benefit to eczema sufferers," said lead researcher Joel Bamford of the University of Minnesota Medical School and Essentia Health System in Duluth, Minnesota, US. "Given the strength of the evidence in our review, we think further studies on the use of these complementary therapies to treat eczema would be hard to justify."
Some participants in the studies experienced mild side effects such as headaches and stomach upsets or diarrhoea as they also did while taking placebos. However, none of the selected studies evaluated or mentioned bleeding or anti-clotting effects, which have previously been associated with evening primrose oil. "Consumers need to be warned that oral evening primrose oil is listed as a known cause of increased bleeding for those taking Coumadin or warfarin, a very common medication," said Bamford.
Source: Eurekalert
