In the initial stage of sepsis, a large amount of IFN‐γ is released, which can promote the activation of GTP‐cyclohydrolase 1 and increase the production of 5,6,7,8‐tetrahydrobiopterin (BH4), a cofactor for phenylalanine hydroxylase (PAH), tyrosine hydroxylase (TH), and tryptophan hydroxylase (TPH), thus affecting the metabolic pathways of phenylalanine, tyrosine, and tryptophan biosynthesis (Hu et al. Here, TPH1 is linked to Sepsis.