SB-203580 is widely used in biomedical research as a selective inhibitor of p38 mitogen-activated protein (MAP) kinase, particularly the alpha and beta isoforms. It is employed to study inflammatory processes, as p38 MAPK plays a key role in the production of pro-inflammatory cytokines such as TNF-α and IL-1β. Researchers use SB-203580 to investigate signaling pathways involved in cellular responses to stress, apoptosis, and differentiation. It has been applied in studies related to autoimmune diseases, neurodegenerative conditions, and cancer to understand how blocking p38 activity affects disease progression. Due to its ability to suppress cytokine production, it has also been explored in models of sepsis and rheumatoid arthritis. However, it is primarily a research tool and not used therapeutically. Its application is limited to in vitro and preclinical in vivo studies to dissect the role of p38 in various cellular functions.