IL17A and ulcerative colitis: The association between IL-17 inhibitors treatment and the onset of IBD was confirmed in a study conducted by Petitpain et al. who analysed 1129 gastrointetinal Individual Case Safety Reports from Vigibase concerning the side effects of IL-17 inhibitors, among which 850 cases of IBD (42.5% Crohn’s disease, 31.9% ulcerative colitis, and 25.6% undifferentiated IBD) were identified [47].