IL17A and psoriasis: However, some studies evidenced that some biologics (e.g., anti-IL17 and the anti-TNF molecules) used for the treatment of psoriasis increased the risk of IBD [35,36,37,38,39], whereas the use of other biological drugs for psoriasis, such as the anti-IL23/IL39 antibodies (guselkumab, tildrakizumab, risankizumab) and anti-IL12/IL-23 inhibitor (ustekinumab), were not associated with the development of IBD [40].