IFNB1 and Headache: Comparing the safety profiles of MS-DMTs, headache is surely a known side effect of IFNβ-1 therapy [40,41,42,43], but some metanalysis reported that it was more common also for alemtuzumab as compared with all the other DMTs and placebo and for cladribine versus natalizumab and for fingolimod versus natalizumab, although the prevalence of headache in some high-efficacy DMTs has not been confirmed by other studies [45,46,47].