By means of immunoinhibition by specific salivary monoclonal antibodies in combination with a chromogenic substrate, assays of serum amylase were performed in control subjects, in chronic alcohol misusers in relapse or remission and in patients with alcoholic liver disease (ALD). There was a selective increase in the salivary isoenzyme in the ALD group. There were no significant changes in either of the alcohol misusing groups, compared with control subjects. It is suggested that the increase in salivary iso-amylase observed in patients with ALD is related to the previously reported functional and histological abnormalities in the parotid glands of this group of patients. It is also suggested that assay of pancreatic iso-amylase may be more discriminatory than total amylase levels in detecting pancreatic disease in patients with alcoholic cirrhosis.