A 65-year-old male patient with type 2 diabetes developed who took linagliptin tablets for 6 months stomatitis liquid. After two weeks of treatment with triamcinolone oral ointment and Kangfuxin liquid, the symptoms did not improve. Clinical pharmacist consultation considered it to be caused by linagliptin tablets and advised the patient to discontinue linagliptin tablets, which was adopted by doctor. And, the patient was referred to the endocrinology department to adjust the glucose-lowering regimen. The oral lesions began to improve three days after discontinuation of the medication, and were completely healed at the third week of follow-up. The Naranjo’s Assessment Scale was used to evaluate the association between linagliptin and stomatitis, with the result indicating ‘possibly related’. Stomatitis is a rare adverse reaction of linagliptin. Conventional local use of corticosteroids and mouthwashes may be ineffective, and timely discontinuation or reduction of the medication is necessary. This article may serve as a reference for clinical management of similar events.

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