ABSTRACT
Background: Coronavirus pandemic has affected a large population worldwide. Currently, the standard care for individuals who are exposed is supportive care, symptomatic management, and isolation. Objectives: This study aimed to evaluate the effects of the combined use of ethanol and dimethyl sulfoxide (DMSO) as a nasal spray in preventing Coronavirus disease 2019 (COVID-19). Methods: This randomized controlled trial was conducted on volunteer healthcare workers of medical centers who were at the forefront of the fight against COVID-19 in Shahroud, Iran. In total, 232 participants were randomly assigned to intervention and control groups to receive DMSO/ethanol or routine care, respectively. The subjects were followed for four weeks to determine the incidence of COVID-19 infection in each group based on the RT-PCR test. Finally, absolute risk difference and relative risk were calculated to evaluate the effect of DMSO on COVID-19 prevention. Results: The results showed that the incidence rates of COVID-19 were 0.07 and 0.008 in the control and intervention groups, respectively. The relative risk was obtained at 0.12 (0.02-0.97) according to the incidence rate in the two groups. Conclusion: Combined administration of DMSO and ethanol by healthcare providers can considerably prevent COVID-19.