Thirty-two children and two adults with chronic atopic dermatitis related to food allergy entered this double-blind crossover study comparing oral sodium cromoglycate (200-1600 mg/24 h) with placebo. Each treatment period comprised 6 weeks: 4 weeks on elimination diet, and 2 weeks on a normal, i.e. unrestricted diet. The diagnosis of food allergy was made after clinical improvement with elimination diet and relapse after challenge. Overall analysis of skin symptoms evaluated by means of clinical assessments and diary cards, opinions of treatment, and use of concomitant medication gave no evidence of any difference between sodium cromoglycate and placebo. Unusual symptoms were reported by 18 patients. In one case the patient was withdrawn during the sodium cromoglycate period because of side effects. The majority of symptoms with both treatments were stomach problems. Overall analysis of the laboratory data gave no significant differences between treatments.