Two com. chymopapain [9001-09-6] formulations Chymodiacetin and Discase, when examined by 2 independent assay methods, showed different relative activities. The methods used, active-site titration and a conventional synthetic substrate assay, consistently showed that Chymodiacetin had a higher enzyme activity than Discase. The relative stabilities after reconstitution as direct by the manufacturers were also different between the 2 products. Chymodiacetin retained 95% of its initial potency after 24 h at 22°, but Discase showed only 80% of its initial potency after 2 h, 65% after 4 h, and 13% after 24 h. Chymodiacetin exhibits greater relative activity and reconstituted stability compared with Discase.