Thirty-five children (aged 1-15 years) with atopic dermatitis due to food allergy were treated with oral cromolyn sodium (also called sodium cromoglycate). The initial dose was 100 mg/day; this was increased progresively to 200-600 mg/day, depending on the response. The treatment improved the skin lesions and prevented reactions to allergenic foods. In most cases, the effects were noticeable after two weeks. The effective dose varied from patient to patient. Cromolyn was ineffective in patients with raised IgG4 levels.

Comment: Cromolyn sodium is a synthetic compound that consists of two molecules of quercetin bound together. It has been shown to inhibit mast cell degranulation, which is one of the mediators of allergic reactions. Both open and controlled trials have found that cromolyn sodium can block food-allergic reactions and ameliorate a wide array of symptoms that result from food allergies. In addition to inhibiting the immune response in the gut wall, cromolyn sodium prevents antigen entry into the circulation. The medication is fairly well tolerated, although in it's most readily available form (Gastrocrom®) it is rather expensive. Less expensive generic versions can be obtained through compounding pharmacists.

While this treatment does not address the cause of food allergies, and while avoidance of allergenic foods is preferable, cromolyn sodium can be considered for people who are unable or unwilling to stop eating their allergens. Moreover, continued use of cromolyn sodium might reduce a person's allergic reactivity, in the same way that avoiding the allergens would. Some practitioners have used quercetin to block food allergies, but there are no published reports on its efficacy.

Molkhou P, Waguet JC. Food allergy and atopic dermatitis in children: treatment with oral sodium cromoglycate. Ann Allergy 1981;47:173-175.