This study investigates the efficacy of tocilizumab, an IL-6 receptor inhibitor, in treating severe and critical cases of COVID-19. The researchers analyzed 21 patients who were treated with tocilizumab in addition to routine therapy between February 5 and 14, 2020. The results showed that fever returned to normal on the first day, and other symptoms improved significantly within a few days. Within five days after treatment, 75% of the patients had reduced their oxygen intake, and one patient no longer needed oxygen therapy. CT scans indicated that lung lesions absorbed in 90.5% of the patients. The percentage of lymphocytes in peripheral blood, which was decreased in 85% of the patients before treatment, returned to normal in 52.6% of the patients on the fifth day after treatment. C-reactive protein levels significantly decreased in 84.2% of the patients. No serious adverse reactions were observed. On average, all patients were discharged 15.1 days after receiving tocilizumab. The study concludes that tocilizumab is an effective treatment for severe and critical COVID-19 patients, potentially reducing mortality by curbing the inflammatory storm caused by high levels of IL-6.This study investigates the efficacy of tocilizumab, an IL-6 receptor inhibitor, in treating severe and critical cases of COVID-19. The researchers analyzed 21 patients who were treated with tocilizumab in addition to routine therapy between February 5 and 14, 2020. The results showed that fever returned to normal on the first day, and other symptoms improved significantly within a few days. Within five days after treatment, 75% of the patients had reduced their oxygen intake, and one patient no longer needed oxygen therapy. CT scans indicated that lung lesions absorbed in 90.5% of the patients. The percentage of lymphocytes in peripheral blood, which was decreased in 85% of the patients before treatment, returned to normal in 52.6% of the patients on the fifth day after treatment. C-reactive protein levels significantly decreased in 84.2% of the patients. No serious adverse reactions were observed. On average, all patients were discharged 15.1 days after receiving tocilizumab. The study concludes that tocilizumab is an effective treatment for severe and critical COVID-19 patients, potentially reducing mortality by curbing the inflammatory storm caused by high levels of IL-6.