Risk of an Immediate-type Allergy to Minocycline Hydrochloride Ointment

<p> Minocycline hydrochloride ointment is applied to periodontal pockets to treat periodontal disease. We encountered a case of an immediate-type allergy to minocycline hydrochloride dental ointment, despite the absence of a history of allergies to antibiotics.</p><p> Case report: The patient was a 72-year-old female, with no significant medical history. Systemic erythema and urticaria developed in June 2017. Similar symptoms occurred again in October and November 2017, for which she consulted for an internal medicine examination. However, the cause remained unknown. Because the symptoms always occurred after she received treatment for periodontal disease, we performed a prick test to diagnose any possible allergy caused by the materials used in her dental treatment. A positive reaction to the allergy test was reported for minocycline hydrochloride ointment. We informed her dentist and requested that periodontal maintenance treatment with minocycline hydrochloride ointment be ceased.</p><p> Course: She has not exhibited any allergic symptoms since the application of minocycline hydrochloride ointment was stopped.</p><p> Discussion: It was suspected that allergic symptoms could have developed during the course of periodontal maintenance treatment. Given that the incidence of allergic reactions is increasing, it is important to consider the possibility of allergic reactions to dental materials and medicaments.</p><p> Conclusion: An incremental application of a small amount of topical dental antibiotics into the periodontal pocket can result in immediate-type allergic reaction.</p>