The present disclosure provides, inter alia, methods of treating generalized pustular psoriasis (GPP) by administering an effective amount of a Chemokine Receptor 6 (CCR6) antagonist and/or a C-X-C motif chemokine receptor 2 (CXCR2) antagonist. Also provided herein are methods of modulating dysregulated IL-36 signaling in a subject in need thereof and methods of reducing neutrophil, inflammatory dendritic cell (iDC), and/or CD4 T cell accumulation in a subject in need thereof, said methods, include dministering an effective amount of a Chemokine Receptor 6 (CCR6) antagonist and/or a C-X-C motif chemokine receptor 2 (CXCR2) antagonist. In some embodiments, the CCR6 and/or CXCR2 antagonist has the formula (A):