【Abstract】Objective To explore the efficacy of Desloratadine combined with Dexamethasone or BCGpolysaccharide nucleic acid (BCGPSN) in the treatment of patients with contact allergic dermatitis and effects on serum inflammatory factors. Methods Eighty-two patients with contact allergic dermatitis were selected as study subjects. The patients were divided into DD group and DB group according to the random number table method, with 41 cases in each group. DD group was given Desloratadine combined with Dexamethasone for treatment while DB group was given Desloratadine combined with BCGPSN for treatment. Before treatment and after 1 week and 1 month of treatment, the levels of serum interferonγ (IFNγ), interleukin4 (IL4), total immunoglobulin E (IgE) and soluble Fc segment highaffinity receptor (sFcεRⅠ) were compared between the two groups, and the treatment effects after 1 month of treatment and the incidence rate of adverse drug reactions within 1 month were analyzed in the two groups. Results After 1 week and 1 month of treatment, the levels of serum IFNγ and sFcεRⅠ in DB group were significantly higher than those before treatment, and were significantly higher than those in DD group (P＜005). The levels of serum IL4 and total IgE in the two groups were significantly lower than those before treatment, and the levels in DB group were significantly lower than those in DD group (P＜005). The treatment effects in DB group were significantly better than those in DD group, and the effective rate of treatment was significantly higher than that in DD group (P＜005). However, there was no significant difference in the incidence rate of adverse drug reactions between the two groups within 1 month (P＞005). ConclusionDesloratadine combined with BCGpolysaccharide nucleic acid has more ideal effects than Desloratadine combined with Dexamethasone in the treatment of contact allergic dermatitis, and it has good drug safety, and it is beneficial to the prognosis and recovery of patients.