An outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which began in Wuhan, China in December 2019, has rapidly spread all over the world. The World Health Organization characterized the disease caused by SARS-CoV-2 (COVID-19) as a pandemic in March 2020. In the absence of specific treatments for the virus, treatment options are being examined. Drug repurposing is a process of identifying new therapeutic uses for approved drugs. It is an effective strategy to discover drug molecules with new therapeutic indications. This strategy is time-saving, low-cost, and has a minimal risk of failure. Several existing approved drugs such as chloroquine, hydroxychloroquine, doxycycline, azithromycin, and ivermectin are currently in use because of their efficacy in inhibiting COVID-19. Multidrug therapy, such as a combination of hydroxychloroquine and azithromycin, a combination of doxycycline and ivermectin, or a combination of ivermectin, doxycycline, and azithromycin, has been successfully administered. Multidrug therapy is efficacious because the mechanisms of action of these drugs differ. Moreover, multidrug therapy may prevent the emergence of drug-resistant SARS-CoV-2.
Keywords: COVID-19; azithromycin; doxycycline; hydroxychloroquine; ivermectin.