Admitted patients with COVID-19 Moderate to severe disease Stable patients Patients should not have bleeding disorders Patients do not have a history of heart attack and stroke Patients without history of ocular or cerebral hemorrhage No pregnancy or breastfeeding Patients without history of intolerance to PTX or other xanthines such as caffeine, theophylline and tobromine Patients without gastric ulcers Patient without history of porphyria Patients with no prominent renal or hepatic or cardiac dysfunction Patients without history of major surgery in the past 2 weeks Patients without history of cancer Patients without need to use any therapeutic blood thinners, including aspirin and warfarin

Admitted patients with COVID-19 Moderate to severe disease Stable patients Patients should not have bleeding disorders Patients do not have a history of heart attack and stroke Patients without history of ocular or cerebral hemorrhage No pregnancy or breastfeeding Patients without history of intolerance to PTX or other xanthines such as caffeine, theophylline and tobromine Patients without gastric ulcers Patient without history of porphyria Patients with no prominent renal or hepatic or cardiac dysfunction Patients without history of major surgery in the past 2 weeks Patients without history of cancer Patients without need to use any therapeutic blood thinners, including aspirin and warfarin