Therapeutic monoclonal antibodies are henceforth commonly used in the management of psoriasis but have been also used more recently in chronic spontaneous urticaria and atopic dermatitis. Three examples are developed herein: dupilumab, omalizumab and lanadelumab. The specificity of their mechanism of action results from a better understanding of the inflammatory pathways in these chronic diseases, which previously shared either the same targeted topical or systemic treatments. However, their high costs should be put into perspective with the epidemiology, the precise evaluation of the severity, the optimization of first line treatments and the long-term benefit/risk ratio.