Inclusion Criteria:  Adult, hospitalized severe COVID-19 patients; both genders; given informed consent (COVID-19 infection confirmed by PCR, severe illness is defined as patients with SpO2 ≤94% on room air, including patients on supplemental oxygen).  Exclusion Criteria:  patients under 18 years old, pregnant ladies, advanced renal diseases (cr. Clearance < 30 ml/hr), raised liver enzymes> 3 folds of normal, arrhythmia.