Background: Preprints are preliminary reports that have not been peer-reviewed. On Dec 2019, a novel coronavirus appeared in China, and since then, scientific production, including preprints, has drastically increased. In this study, we intend to evaluate how often preprints regarding pharmacological interventions against COVID-19 were cited, in spite of the fact that some of these preprints remained unpublished.Methods: We conducted a search on medRxiv and bioRxiv to identify preprints related to pharmacological interventions against SARS-CoV-2 from Jan 1st to Mar 31, 2020. We gathered metadata on included preprints and identified if they had been published in a peer-reviewed journal. We performed Mann-Whitney U tests to evaluate if published articles had differences in citation numbers or usage, as defined by PDF downloads and abstract views, when compared to preprints that were not published.Results: Our sample included 97 preprints, of which only 14 were published on peer-reviewed journals and 83 remained unpublished. The most common study designs we found among preprints were basic science research and case series. Published articles had a significantly higher number of citations and metrics (PDF and abstract downloads) when compared to unpublished preprints.Conclusions: The use of preprints during this pandemic has been higher than in previous outbreaks, however, the publication rate in peer-reviewed journals in our sample was low. Preprints should be used as a mean to display preliminary data rapidly in order to obtain feedback by the scientific community, or to guide further research. However, due to the lack of peer-review, and potentially flawed data analysis, preprints alone should not be used to guide clinical practice, as the risk of unwarranted modifications to management is concerning.