Eczema is an itchy and, to some, an embarrassing skin ailment. Typical medial treatments like cortisone are less than ideal.
So some people have turned to evening primrose oil, a remedy made from the seeds of a yellow wildlflower that are rich in the essential fatty acid gamma-linolenic acid.
There's only problem: evening primrose oil doesn't seem to work. A review of studies that tested the effectiveness of evening primrose oil found that it offered no improvement of symptoms compared with placebos like olive oil or paraffin oil. The supplement is taken orally in capsules.
The review looked at 19 studies testing evening primrose oil. Eight others tested borage oil, another plant-based remedy. They involved almost 16,000 adults and children in 12 countries. None of the studies found any benefit from evening primrose oil or borage oil.
While eczema is common, affecting as many as 20 percent of childrenm, most outgrow it. But the itchy, swollen skin can be uncomfortable and unsightly.
The study authors don't hold out much hope that more research will find some benefit, saying that the strength of these studies makes it hard to justify further testing. They also note that evening primrose oil can keep blood from clotting and can be dangerous in people taking blood thinners, and that borage contains a compound that can be toxic to the liver.
The report was published in the Cochrane Database of Systematic Reviews, which is considered the gold standard for evidence-based medicine.
As dietary supplements, alternative remedies like evening primrose oil aren't tested for safety and efficacy with the rigor that's applied to prescription medications.
Since 1998 the National Institutes of Health has put millions of dollars into studying popular alternative remedies — from yoga to chelation — to see if they work. The National Center for Conventional and Alternative Medicine's current budget is $128 million a year.
So, the good news is that we're finally getting the kinds of studies that will help people make informed choices about alternative remedies.
The not-so-good news, at least if you're selling evening primrose oil, is that those kinds of studies may show that it's not all it has been cracked up to be.