Cimetidine does not influence immunological parameters in man

Abstract The influence of cimetidine on several immunological parameters was studied over a 3-week period in 9 patients with peptic disease, before, during, and 2 days after treatment with 1.6 g cimetidine daily. No change was observed in the reaction to skin tests with candida albicans, mumps, trichophyton, intermediate-strength purified protein derivative, and varidase (streptokinase + streptodornase) in patients as compared to 11 controls. There was no change in total lymphocyte counts, nor in the results of lymphocyte transformation tests stimulated by phytohemagglutinin, pokeweed mitogen, or a cocktail of the antigens as used for skin testing. Results of mixed lymphocyte cultures were not altered and the stimulating and responding capacity of lymphocytes in one-way MLC remained unchanged. No difference was observed in IgG, IgA, or IgM levels, and all were in the normal range.