[Changes in serum immunoglobulins in allergic rhinitis induced by histamine H2 antagonists]

The authors discuss their double-blind experiments on 40 allergic rhinitis affected patients, aged 15 to 50 years. Twenty were treated with H2 antagonists (Cimetidine) and twenty with placebo. The clinical assessment of the effectiveness of the treatment was carried out on a range of subjective and objective parameters taken before and after treatment. The IgE, IgA, IgG and IgM serum rate was measured. An improvement in the symptomatology was noted in 15 of the 20 Cimetidine treated patients and none in the placebo group. The results have shown a significant percentage decrease in the total serum IgE values after treatment, compared to initial ones, while no significant change was observed in the values of IgA, IgG and IgM. This decrease in IgE is thus a specific class. As it has been demonstrated that a subpopulation of lymphocyte T suppressors acts selectively on IgE producing B cells, the authors believe that only on these elements, carriers of H2 membrane receptors, can Cimetidine act to induce a decrease in total serum IgE levels and therefore a reduction in degranulation processes.