CALCA and migraine disorder: The olcegepant trial concluded that the worse 72-hour survival rate observed in the treatment group could be explained by unstable hemodynamics.12 In addition, a recent meta-analysis found that patients hospitalized with COVID-19 had better survival if they experienced headache as a symptom.31 Considering the role of CGRP in migraine pathophysiology, the authors hypothesized that an increase in the CGRP level, which triggered headache as 1 of the COVID-19 symptoms, is a host compensatory response against COVID-19.