IL13 and pulmonary fibrosis: Studies have indicated that eucalyptol can alleviate bleomycin-induced pulmonary fibrosis, suppressing the expression of arginase-1, Ym-1, IL-13, and transforming growth factor (TGF)-β1, as well as reducing the production of IL-13, IL-6, and TNF-α, which inhibits M2 macrophage polarization [213].