Since abnormal concentrations of immunoglobulins have previously been found in saliva of patients with Crohn's disease, we measured the concentrations of IgA, IgM, and IgG in whole and parotid saliva with the ELISA technique in 20 patients with ulcerative colitis (UC) and 19 healthy control subjects. IgA predominated in whole and parotid saliva in both patients and controls, and in both groups whole saliva had higher levels of IgA, IgM, and IgG than did parotid saliva. IgA and IgG levels were significantly (p less than 0.05) elevated in the whole saliva of UC patients as compared with the controls. IgM was also increased, but the difference did not reach statistical significance. No correlation was found between immunoglobulin levels and age, sex, duration of the disease, and extent of colitis. A significant negative correlation was found between the activity of the disease and the concentration of IgA in whole saliva. The present study therefore suggests that the previously reported abnormalities in the saliva of patients with Crohn's disease and presented as possible evidence for a disease affecting the whole of the gastrointestinal tract, are not specific, since similar findings are observed in UC.