Key message: Oral evening primrose oil and borage oil are not effective treatments for eczema
Anyone who suffers from eczema, or is close to someone who has it, knows that this common skin condition can be a real misery. In the developed world it’s on the increase. Treatments can be very time-consuming and many people struggle to find effective relief from the itching and help for sore, weeping, cracked or bleeding skin. Some people use complementary therapies, including evening primrose oil (EPO) and borage oil (BO) taken by mouth, but to date it has been unclear whether these are effective and safe.
Back in 2003, the Cochrane Skin Group‘s Co-ordinating Editor Hywel Williams, who is Professor of Dermato-Epidemiology at the University of Nottingham, wrote in the BMJ that it was time to say goodnight to evening primrose oil for eczema. I would urge you to read this short article, freely available from the link below, which tells the chequered history of the development of EPO, which has been “marred by lack of data in the public domain”. Clearly this is still a problem, as it is in all areas of medicine; if you aren’t aware of the All Trials campaign then please click here to find out why we need to demand that all trials are registered and all results reported and what you can do to help.
The Cochrane Skin Group has just published a new review which brings together evidence from 27 randomized trials involving almost 1600 children and adults with eczema; 11 studies were unpublished drug company studies. 19 assessed EPO and 8 BO. Participants took EPO or BO or a placebo (a ‘dummy’ oil such as olive oil) for between 3 and 24 weeks.
What did they find?
- EPO and BO were no better than placebo oils in improving eczema symptoms
- Mild side effects, such as stomach upsets, were experienced in both treatment and placebo groups, with no difference between them
How good was the evidence and what are the gaps?
- The evidence was pretty good quality in that most of the studies were judged to be at low risk of bias
- Studies consistently showed no benefit of EPO or BO over placebo oils
- Differences between the studies and the ways in which results were reported limited the extent to which results could be combined. The results from 8 EPO studies could be combined in a meta-analysis
- Missing data was a problem and attempts to get this missing data were unsuccessful
- Trials were small; in some as few as 12 people took part and the largest involved only 160
- Only two studies of EPO measured improvement in quality of life and only one gave the results for this outcome, finding no benefit of EPO. No firm conclusions can be drawn
- None of the studies evaluated bleeding or anti-clotting effects, which have previously been associated with EPO and which is listed as a known cause of increased bleeding for people taking the medicine warfarin
- None of the studies reported costs
- All but one study took place in developed countries so results may not be generalizable elsewhere
Lead researcher Joel Bamford said
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.
On the evidence of this review, EPO and BO represent a waste of money for eczema sufferers looking for relief from their symptoms. What’s more, previous research has shown that for anyone taking warfarin there’s an increased risk of bleeding when taking EPO. Both EPO and BO are commercially advertised on the internet as treatments for eczema – surely it’s time that changed?
Bamford JTM, Ray S, Musekiwa A, van Gool C, Humphreys R, Ernst E. Oral evening primrose oil and borage oil for eczema. Cochrane Database of Systematic Reviews 2013, Issue 4. Art. No.: CD004416. DOI: 10.1002/14651858.CD004416.pub2.
Williams HC. Evening primrose oil for atopic dermatitis. Time to say goodnight. BMJ. 2003 December 13; 327(7428): 1358–1359. doi: 10.1136/bmj.327.7428.1358