Serum mucoprotein level is a monitor for inflammatory bowel disease activity although its method of measurement is laborious. An easier assay of alpha 1 acid glycoprotein is described. The ability of the two proteins to differentiate active from non-active cases was evaluated and the results compared with acute inflammatory reactants such as alpha 1 antitrypsin and haptoglobin. Amongst 79 patients with inflammatory bowel disease linear discriminant analysis was used to segregate overlapping ranges for patients with and without active disease and thus enabling the evaluation of sensitivity and specificity of each test. Predictive values of 78.6% for mucoprotein and 76.7% for alpha 1 acid glycoprotein were achieved and were due to the fact that there is a very strong linear correlation between these two proteins (r = 0.83, p less than 0.01). Furthermore the mucoprotein fraction is predominantly comprised of alpha 1 acid glycoprotein by as much as 91.5%. alpha 1 antitrypsin and haptoglobin showed poor predictive values. Pairing up all the proteins each with mucoprotein improved the sensitivity, specificity, and predictive value slightly. As a single test alpha 1 acid glycoprotein gave highest specificity, proved easy to assay and was automatable. It was therefore recommended as a substitute for serum mucoprotein in routine assays and as an effective monitor and predictor of inflammatory bowel disease.