Topical Application of Aprepitant Inhibits Erlotinib-Induced Facial Dermatitis and Hair Loss

The study investigated the protective effects of topical aprepitant, a substance P receptor blocker, against erlotinib-induced facial dermatitis and hair loss in rats. Erlotinib, an EGFR-TKI used for cancer treatment, caused significant skin toxicity, including facial rash and hair loss, after 6 weeks of administration. Topical aprepitant applied 3 times a week reduced these side effects by up to 70%, comparable to oral doses. The treatment also inhibited neutrophil superoxide and plasma 8-isoprostane levels, and reduced leukocyte infiltration in the skin. The findings suggest that neurogenic inflammation and reactive oxidative species play a critical role in EGFR-TKI-induced skin toxicity, and blocking substance P can significantly mitigate these effects.