Evening primrose oil and borage oil do not help eczema symptoms, finds Cochrane reviewBMJ 2013; 346 doi: http://dx.doi.org/10.1136/bmj.f2712 (Published 29 April 2013) Cite this as: BMJ 2013;346:f2712
Evening primrose oil and borage oil do not improve the symptoms of eczema, a review of the evidence has found. Furthermore, both can cause harm, mainly to the gastrointestinal tract.
The authors, who published their review in the Cochrane Library, concluded that it would be hard to justify further studies on the treatments.1
Some people take evening primrose oil and borage oil because they contain γ linolenic acid, which was once thought to have anti-inflammatory properties. The Cochrane review cites research that found that in 2007 nearly four in 10 adults (38%) and one in 10 children with eczema took some form of complementary treatment.
The Cochrane researchers found 27 randomised controlled trials that looked at the effects of either evening primrose oil (19) or borage oil (8) in 1596 adults or children with eczema. They were treated for between three and 24 weeks.
The researchers were able to do a meta-analysis of some studies of evening primrose oil. They found that patients and doctors did not judge symptoms to have improved in comparison with placebo on a visual analogue scale of 0 to 100 (mean difference for patients −2.2 (95% confidence interval 10.5 to 6); doctors −3.3 (−7 to 0.5)).
Treatment with borage oil also failed to improve symptoms, although the researchers were unable to conduct a meta-analysis because of the different way the results were reported.
The review’s lead author, Joel Bamford, of the University of Minnesota Medical School and Essential Health System in Duluth, Minnesota, said, “There is no evidence that taking either evening primrose or borage oil is of benefit to eczema sufferers. 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.”
Patients taking the complementary treatments and the placebos reported side effects that included headaches, stomach upsets, and diarrhoea. None of the selected studies evaluated or mentioned bleeding or anti-clotting effects, which had 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.
Cite this as: BMJ 2013;346:f2712