Although the COVID-19 pandemic confers a strong incentive on the medical community to act, we must remain adherent to evidence-based medicine and ethical considerations before changing guidelines from common practice, especially in prophylactic treatment of individuals. Consequently, there is a need for high-quality observational studies to better detail the incidence of VTE and bleeding events in individuals with COVID-19. There is also a need for information on risk factors and development of validated VTE and bleeding risk prediction models to identify those individuals with COVID who might benefit most from thromboprophylaxis. Even more importantly, we need well-conducted clinical trials on thromboprophylaxis in COVID-19 that explore clinically meaningful outcomes including symptomatic VTE, major bleeding events and death. These studies are needed to ensure that we do not harm patients, and may inform physicians and policy-makers of the most efficient use of already heavily strained health-care resources.