OBJECTIVE Cinnamomum cassia has been used in traditional medicine in East Asian countries to treatallergic disease.Previous studies have demonstrated that C.cassiainhibits the development of mite antigen-induced skin lesions in NC/Nga mice by suppressing the Thelper 2cell response.The objective of this study is to investigate whether C.cassia has an efficient inhibition on systemic anaphylaxis and contact hypersensitivity in mice.METHODS To induce systemic anaphylaxis,mice were injected intraperitoneally with compound 48/80.Mortality was monitored for 1h after the injection.Contact hypersensitivity reaction was induced by topical application of 2,4-dinitrofluorobenzene(DNFB)to the ears of mice.After DNFBchallenge,ear thickness was measured 0,24 and 48h.RESULTS We discovered that C.cassia significantly inhibited compound 48/80-induced anaphylaxis and DNFB-induced ear swelling.Compound 48/80-induced anaphylaxiswas completely inhibited at the dose of 60mg·kg-1 body weight.Ear swelling at 24 h after DNFB-challenge was significantly less than that in the control group(0.16±0.03 vs.0.32±0.03 mm,P<0.01),while C.cassia was administered at the dose of 200mg·kg-1.CONCLUSION These findings indicate that C.cassiasuppresses allergic reactions,thus has potential value for mitigation of atopic dermatitis. OBJECTIVE Cinnamomum cassia has been used in traditional medicine in East Asian countries to treatallergic disease. Previous studies have demonstrated that C. cassia inhibits the development of mite antigen-induced skin lesions in NC / Nga mice by suppressing the Thelper 2 cell response. Objective of this study is to investigate whether C. cassia has an efficient inhibition on systemic anaphylaxis and contact hypersensitivity in mice. METHODS To induce systemic anaphylaxis, mice were injected intraperitoneally with compound 48/80. MORTITY was monitored for 1 h after the injection. Contact hypersensitivity reaction was induced by topical application of 2,4-dinitrofluorobenzene (DNFB) to the ears of mice. After DNFB challenge, ear thickness was measured 0,24 and 48h. RESULTS We discovered that C. cassia significantly inhibited compound 48/80-induced anaphylaxis and DNFB -induced ear swelling. Compound 48/80-induced anaphylaxis was completely inhibited at the dose of 60 mg · kg -1 body weight. Ear swelling at 24 h after DNFB-challenge was significantly less than that in the control group (0.16 ± 0.03 vs.0.32 ± 0.03 mm, P <0.01) while C. cassia was administered at the dose of 200 mg · kg-1.CONCLUSION These findings indicate that C.cassiasuppresses allergic reactions, thus has potential value for mitigation of atopic dermatitis.