Eczema is a common inflammatory condition of the skin.
Many skin diseases cause symptoms similar to those of eczema, so it is important to have the disease properly diagnosed before it is treated
What are the symptoms of eczema?
Eczema is characterized by scaling, thickened patches of skin that can become red and fissured. It may also appear as tiny blisters (called vesicles) that rupture, weep, and crust over. The most troublesome and prevalent symptom of eczema is itching, which may be constant.
Dietary changes that may be helpful for eczema
Eczema can be triggered by allergies.1 2 Most children with eczema have food allergies, according to data from double-blind research.3 A doctor should be consulted to determine whether allergies are a factor. Once the trigger for the allergy has been identified, avoidance of the allergen can lead to significant improvement.4 However, “classical” food allergens (e.g., cows’milk, egg, wheat, soy, and nuts) are often not the cause of eczema in adults. A variety of substances have been shown, in a controlled trial, to trigger eczema reactions in susceptible individuals; avoidance of these substances has similarly been shown to improve the eczema. Triggers included food additives, histamine, salicylates, benzoates, and other compounds (such as aromatic compounds) found in fruits, vegetables, and spices.5 These reactions do not represent true food allergies but are instead a type of food sensitivity reaction. The authors of this study did not identify which substances are the most common triggers.
It has been reported that when heavy coffee drinkers with eczema avoided coffee, eczema symptoms improved.6 In this study, the reaction was to coffee, not caffeine, indicating that some people with eczema may be allergic to coffee. People with eczema who are using a hypoallergenic diet to investigate food allergies should avoid coffee as part of this trial.
Researchers have reported that people with eczema do not have the normal ability to process fatty acids, which can result in a deficiency of gamma-linolenic acid (GLA).7 GLA is found in evening primrose oil (EPO), borage oil, and black currant seed oil. Some,8 9 10 but not all,11 12 13 14 double-blind trials have shown that EPO is useful in the treatment of eczema. An analysis of nine trials reported that the effects for reduced itching were most striking.15 Much of the research uses 12 pills per day; each pill contains 500 mg of EPO, of which 45 mg is GLA. Smaller amounts have been shown to lack efficacy.16
Supplementation with borage oil, another source of GLA, has led to reductions in skin inflammation, dryness, scaliness, and itch in eczema patients in some,17 but not all, preliminary18 or double-blind trials.19
Many years ago, use of large amounts of vegetable oil (containing precursors to GLA) was reported to help treat people with eczema,20 21 but these studies were not controlled and do not meet modern standards of research.
Ten grams of fish oil providing 1.8 grams of EPA (eicosapentaenoic acid) per day were given to a group of eczema sufferers in a double-blind trial. After 12 weeks, those using the fish oil experienced significant improvement.22 23 According to the researchers, fish oil may be effective because it reduces levels of leukotriene B4, a substance that has been linked to eczema.24 The eczema-relieving effects of fish oil may require taking ten pills per day for at least 12 weeks. Smaller amounts of fish oil have been shown to lack efficacy.25
One trial using vegetable oil as the placebo reported that fish oil was barely more effective than the placebo (30% vs. 24% improvement).26 As vegetable oil had previously been reported to have potential therapeutic activity, the apparent negative outcome of this trial should not dissuade people with eczema from considering fish oil.
Although supplementation with 400 IU of vitamin E per day has been reported in anecdotal accounts to alleviate eczema,27 research has not supported this effect.28 Moreover, rare cases of topical vitamin E potentially causing eczema have appeared.29 People with eczema should not expect vitamin E to be helpful with their condition.
A double-blind trial reported that use of a hypoallergenic infant formula plus probiotics (500 million organisms of Lactobacillus GG bacteria per gram of formula, taken for one month) initially led to improvement in eczema symptoms in infants with suspected allergy to cows’milk.30 However, by the end of two months, both the group receiving Lactobacillus GG and the placebo group had improved approximately the same amount. In the same report, a preliminary trial giving 20 billion Lactobacilli twice per day to breast-feeding mothers led to significant improvement of their allergic infants’ eczema after one month. Probiotics may reduce allergic reactions by improving digestion, by helping the intestinal tract control the absorption of food allergens, and/or by changing immune system responses.
In 1989, Medical World News reported that researchers from the University of Texas found that vitamin C, at 50–75 mg per 2.2 pounds of body weight, reduced symptoms of eczema in a double-blind trial.31 In theory, vitamin C might be beneficial in treating eczema by affecting the immune system, but further research has yet to investigate any role for this vitamin in people with eczema.
Are there any side effects or interactions with eczema?
Refer to the individual supplement for information about any side effects or interactions.
Herbs that may be helpful for eczema
The table below summarizes the three categories of herbs used for people with eczema: anti-inflammatories and herbs that affect the immune system (immunomodulators), astringents (herbs that bind fluids and exudates), and herbs that affect the liver (also called alteratives). Alterative herbs are poorly researched. Astringents are only helpful if applied topically when weeping eczema is present; they will not help people with dry eczema.
Zemaphyte®, a traditional Chinese herbal preparation that includes licorice as well as nine other herbs, has been successful in treating childhood and adult eczema in double-blind trials.32 33 34 One or two packets of the combination is mixed in hot water and taken once per day. Because one study included the same amount of licorice in both the placebo and the active medicine, it is unlikely that licorice is the main active component of Zemaphyte®.35
Several Chinese herbal creams for eczema have been found to be adulterated with steroids. The authors of one study found that 8 of 11 Chinese herbal creams purchased without prescription in England contained a powerful steroid drug used to treat inflammatory skin conditions.36
A cream prepared with witch hazel and phosphatidylcholine has been reported to be as effective as 1% hydrocortisone in the topical management of eczema, according to one double-blind trial.37
Topical applications of chamomile have been shown to be moderately effective in the treatment of eczema.38 39 One trial found it to be about 60% as effective as 0.25% hydrocortisone cream.40
Onion injections into the skin and topical onion applications have been shown to inhibit skin inflammation in people with eczema, according to one double-blind trial.41 The quantity or form of onion that might be most effective is unknown.
A Japanese topical ointment called Shiunko has been reported to help improve symptoms of eczema, according to preliminary research.42 The ointment contains sesame oil and four herbs (Lithospermum radix, Angelica radix, Cera alba and Adeps suillus) and was applied twice daily along with petrolatum and 3.5% salt water for three weeks. Clinical improvement was seen in four of the seven people using Shiunko.
Topical preparations containing calendula, chickweed, or oak bark43 have been used traditionally to treat people with eczema but none of these has been studied in scientific research focusing on people with eczema.
Burdock, sarsaparilla, red clover, and wild oats have been used historically to treat people with eczema, but without scientific investigation.
Are there any side effects or interactions with eczema?
Refer to the individual herb for information about any side effects or interactions.
Holistic approaches that may be helpful for eczema
Numerous trials have reported that hypnosis improves eczema in children and adults.44 A preliminary trial emphasizing relaxation, stress management, and direct suggestion in hypnosis showed reduced itching, scratching, and sleep disturbance, as well as reduced requirements for topical corticosteroids. All of the patients studied had been resistant to conventional treatment.45