A trace element preparation (Béres Drops Plus, BDP) elevates the number of glucocorticoid receptors (gcR) in peripheral lymphocytes isolated both from healthy blood donors and rheumatoid arthritis patients. This enhancement by BDP was found either for constitutive expression of gcRs or in experiments when the lymphocytes were stimulated by interleukin (IL)-6. There was no significant effect of BDP on IL-1 and tumour necrosis factor alpha (TNF alpha)-induced changes of gcRs. The effect of BDP was greatly dependent on the presence of Zn++ ions in the preparation, since the augmenting effect was abolished if BDP did not contain zinc.