Plasma concentrations of interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and tumour necrosis factor alpha (TNFalpha) were measured in 10 elderly women with major depressive disorder (MDD) and in two groups of controls, one consisting of 10 age-matched healthy female volunteers and one consisting of 10 young healthy female volunteers. The cytokine concentrations were measured in MDD patients before and after 30 days of treatment with phosphatidylserine (BC-PS), 600 mg daily p.o. The plasma IL-Ibeta, IL-6 and TNFalpha concentrations did not differ significantly in young controls, elderly controls and MDD patients. BC-PS therapy, while significantly improving the depressive symptoms, did not alter the cytokine concentrations.