Objective To investigate the acute toxicology and intervention effect of Panacis Majoris Rhizoma on rats with chronic pharyngitis.Methods A single,maximum dose of Panacis Majoris Rhizoma(74.4 g·kg-1)was administered to Kunming mice to evaluate its toxicity,involving the assessment of the survival status of the mice,organ indices,morphological changes in major organs,blood routine,and biochemical indicators.SD rats were randomly divided into the control group,model group,prednisone group(6.25 mg·kg-1),and low-,medium-,and high-dose Panacis Majoris Rhizoma groups(0.58,1.16,and 2.32 g·kg-1).All rats received the corresponding drugs(or normal saline)via intragastric administration once daily for a duration of 30 days.Except the control group,chronic pharyngitis was induced in rats of the other groups by using β-hemolytic streptococcus.Following euthanasia,serum inflammatory levels of interleukin-6(IL-6),cyclooxygenase-2(COX-2),interleukin-1β(IL-1β),intercellular adhesion molecule-1(ICAM-1),C-reactive protein(CRP),tumor necrosis factor(TNF-α),monocyte chemoattractant protein-1(MCP-1),and prostaglandin E2(PGE2)were measured.Additionally,pharyngeal tissues were stained with HE and pathological characteristics were observed.Results Toxicological studies have demonstrated that the administration of Panacis Majoris Rhizoma resulted in significant increase in plasma alanine transaminase levels and spleen index of mice,along with corresponding tissue pathological alterations.Nevertheless,no noteworthy pathological changes were observed in other organs,and there were no notable changes in blood routine and plasma biochemical indicators.Pharmacodynamic investigations have revealed that Panacis Maioris Rhizoma effectively reduces the serum levels of inflammatory factors and improves pathological changes in pharyngeal tissues.Conclusion Panacis Maioris Rhizoma alleviated β-hemolytic streptococcus-induced CP by inhibiting inflammatory responses,and may show potential toxicity to the spleen.