Contact Dermatitis after Prescription of an Ophthalmic Ointment Containing Fradiomycin Sulfate: A Retrospective Database Study Using Japanese Health Insurance Claims Data

BACKGROUND: Topical ointments containing fradiomycin sulfate, such as fradiomycin sulfate/methylprednisolone (F/M) and fradiomycin sulfate/betamethasone sodium phosphate (F/B), are known to cause allergic contact dermatitis (CD) in some patients, especially when used for the periocular region. F/M is commonly prescribed to patients for various conditions; however, there are no reports with respect to the incidence of CD caused by F/M in actual practice. OBJECTIVE: The aim was to investigate the incidence of CD using a data-based retrospective cohort study. METHODS: Using a Japanese health insurance claims database [MinaCare Co. Ltd. healthcare database (MinaCare HDB)], a comparative assessment was conducted of F/M and another combination drug (F/B) and two single-drug treatments (ophthalmic ointments with either an antibiotic or a steroid). The total data set consisted of 1,176,082 individuals in the MinaCare HDB, with 54,016 having received prescriptions for one of the four investigational drug regimens. RESULTS: Overall, the incidences of CD were similar in three of the four groups in this study (F/M 0.091; F/B 0.092; steroids 0.102), while being lower in the fourth group (antibiotics 0.060). Even after confirmation of a diagnosis of CD, prescriptions for the investigational drugs were repeatedly filled for some patients. CONCLUSION: This study demonstrated that there was no clear difference in the incidence of CD after filling prescriptions for F/M, F/B, and ophthalmic ointment containing a steroid, while the incidence with antibiotics was lower by 0.03–0.04 compared with the other groups. Considering the observation that the investigational drugs were repeatedly prescribed even after the diagnosis of CD, it is critical that the risk of CD with these prescribed topical ointments is better understood by primary care physicians in order to take appropriate countermeasures.