SUMMARY.—In patients with atopic dermatitis, eczema and urticaria, systemic treatment with prednisone had no effect on the serum immunoglobulin E level (IgE) but improved their clinical condition. Neither was there any effect on the IgE level after the immunosuppressive, azathioprine. The increased level of IgE found in patients with atopic dermatitis was not seen in those who had been free from symptoms for more than a year even if they had a persistent or recurring eczema of the hands or nummular eczem