As epidermal hyperplasia and inflammation are hallmarks of psoriasis, our new findings indicate that alantolactone can not only alleviate these skin lesions by inhibiting inflammation but also relieve epidermal hyperplasia by reducing the expression of TNF-α, IL-6, IL-1β, IL-8, IL-17A, and IL-23. The gene discussed is IL17A; the disease is psoriasis.