The cone and plate rheological viscometry readings of the sterilized hydrogels of hypromellose 4000 (60 g/L) were investigated by using of the three-parameter Herschel and Bulkley power law and the new empirical two-parameter model. To express the influence of the addition of the isotonic concentration of sodium chloride and/or pilocarpine hydrochloride, respectively, on the viscosity of sterilized hydrogels of hypromellose, the area under rheogram (AUR) data was employed as a multi-point rheological characteristic.