An open, controlled study was carried out in young patients with atopic dermatitis, who during one month received oral anti-psoriatic drug, anapsos (n = 46), or antihistamines (n = 30), simultaneously with topic applications. The activity and extension of the cutaneous lesions improved under both treatments, but more markedly with anapsos in spite of the fact that topical applications did not contain steroids in the group treated with anapsos, and the effect was still appreciable several months after interruption of medication. Anapsos, which was well tolerated, considerably relieved the respiratory symptoms of all patients with asthma. Studies performed on patients with atopic dermatitis have shown high IgE levels, eosinophils and T4 counts, and a marked decrease in T8 suppressor cells in peripheral blood. Our data also show a slight decrease in T8 cells (%), a significant increase in T4 sub-sets (%) and a high T4/T8 ratio as a previously reported by several authors. Such an imbalance between helper and suppresor cells may cause alterations in the response to extrinsic and intrinsic antigens, as shown in particular by the abnormally high IgE levels observed in atopic dermatitis. Anapsos was associated with a correction in T lymphocytes imbalances, specifically through the increase of the initially low T8 cells levels and subsequent normalization of the mean T4/T8 index. The tolerance and promising therapeutic activity of this antipsoriatic drug deserve further research in other conditions characterized by a deficit of suppressor cells.