Definitive antiviral properties are evidenced for niacin, i.e., nicotinic acid (NA), as coronavirus disease 2019 (COVID-19) therapy for both health restoration and prevention, to the level that progression of COVID-19 pathology may follow as an intrinsic function of NA supply. This detailed investigation proposes thorough disentanglement of how the downstream inflammatory propagation of ensuing severe acute respiratory virus 2 (SARS-CoV-2) infection can either be prohibited or reversed upstream out the body to expeditiously restore health with well-tolerated dynamic supplementation of sufficient NA (i.e., ~1-3 grams per day). Culmination of this research leads to realization of the potentially ubiquitous therapeutic and preventive powers of NA against inflammatory disease, in general.