OBJECTIVES: Fradiomycin sulfate - methylprednisolone combination ointment (F/M) is an anti-inflammatory topical drug indicated for ophthalmologic or otorhinolaryngologic diseases marketed in Japan. Contact dermatitis (CD) is one of well-known adverse events provoked by fradiomycin sulfate. The objectives of this study were to investigate the incidence of CD after the prescription of topical drugs containing fradiomycin in clinical practice and to assess background characteristics of the patients who were diagnosed CD by using Japanese healthcare database (HDB). METHODS: The data were extracted from Japanese HDB (MinaCare Co. Ltd) which contained data from people covered by employment-based insurances as of April 2013. We classified the patients into three groups with prescription of F/M, fradiomycin sulfate - betamethasone sodium phosphate combination ointment (F/B, comparable to F/M) or betamethasone sodium phosphate solution (B, as a negative control), respectively. The ICD-10 classification was used to identify CD required medication after the prescription. Background characteristics of the patients who were diagnosed CD after the prescription was also investigated. RESULTS: Out of 1,223,905 patients (male: 531,030, female: 692,875), we have identified the F/M group (20,702 patients), the F/B group (5,540 patients) and the B group (108,810 patients). In the F/M group, CD which was suspected causal relationship with the drug was detected in around 0.25% of patients according to the chronological order of the prescription and diagnosis in claim database. Similar tendency was observed in the F/B group, while lower incidence of CD was observed in the B group. CONCLUSIONS: We utilized MinaCare HDB to assess the incidence of CD required medication after topical drugs prescription in real clinical settings. CD was detected at higher incidence with the drugs containing fradiomycin than steroid alone. While further analysis is needed for more accuracy, our approach designed to diminish limitations’ influences was useful to assess risk and benefit of drugs.