The analysis of pharmacokinetic parameters of protease inhibitors. Chemical structures and administration, distribution, metabolism, and elimination (ADME) parameters for famotidine, ribavirin, lopinavir, and nafamostat, drugs that were evaluated as SARS-CoV2 inhibitors, are shown. The colored zone is a suitable physicochemical space for oral bioavailability obtained using the SWISSADME software. The compounds were scored based on the structure and whether these parameters fit into the values established for each indicator related to oral bioavailability. LIPO (lipophility), SIZE (size), POLAR (polarity), INSOLU (insolubility), INSATU (instauration), and FLEX (flexibility). The 2D structures of each drug are shown with the specific atoms represented as follows: carbon in gray, oxygen in red, nitrogen in blue, and sulfur in yellow.