Pizuglanstat hydrate (TAS-205) is a hematopoietic prostaglandin D synthase (HPGDS) inhibitor. TAS-205 selectively inhibits the synthesis of prostaglandin D2 (PGD2) in cell-based enzymatic tests and in vivo models, and effectively reduces the entry of eosinophils into the nasal cavity and late-stage nasal congestion. When used in combination with montelukast , TAS-205 showed a significant synergistic inhibitory effect; when used in combination with fexofenadine , it also had a certain inhibitory effect on early and late nasal congestion.