This work aimed to evaluate the effects of drug therapies for coronavirus infections. Rapid systematic review with search in the MEDLINE, EMBASE, Cochrane, BVS, Global Index Medicus, Medrix, bioRxiv, Clinicaltrials.gov and International Clinical Trials Registry Platform databases. Thirty-six studies evaluating alternative drugs against SARS, SARS-CoV-2 and MERS were included. Most of the included studies were conducted in China with an observational design for the treatment of COVID-19. The most studied treatments were with antimalarials and antivirals. In antimalarial, the meta-analysis of two studies with 180 participants did not identify the benefit of hydroxychloroquine concerning the negative viral load via real-time polymerase chain reaction, and the use of antivirals compared to standard care was similar regarding outcomes. The available scientific evidence is preliminary and of low methodological quality, which suggests caution when interpreting its results. Research that evaluates comparative efficacy in randomized, controlled clinical trials, with adequate follow-up time and with the methods properly disclosed and subject to scientific peer review is required. A periodic update of this review is recommended.