- For patients not receiving protease inhibitor therapy: bilirubin less than or equal to 1.5 times the upper limit of normal (ULN). For patients receiving protease inhibitor therapy and for whom the elevated bilirubin is felt to be related to this therapy total bilirubin should be less than or equal to 3.7 mg/dl with a direct fraction less than or equal to 0.2 mg/dl.