Bisphosphonates (BPs) are widely used as effective anti-resorptive agents in the treatment of osteoporosis. Although BP-related osteonecrosis of the jaws (BRONJ) is a well-known adverse effect, BP-related oral ulcers are not common. Here we report such a case of BP-related oral ulceration probably caused by an error in how to take the drug. A 91-year-old woman was referred to our department because of oral ulcerations. Her medical history revealed articular rheumatism, dementia, dermatomyositis, and osteoporosis. Clinical examination revealed several ulcerations on the left buccal mucosa, upper lip, soft palate, and tongue. She had been receiving treatment for osteoporosis with alendronate for approximately 10 years and suffered from recurrent oral ulcerations. It was revealed that the patient was inhaling the tablet or placing it in the mouth for an extended period, rather than immediately swallowing the tablet with water. We suspected BPs-related oral ulcerations, so we contacted her prescriber to change the medication. Three weeks after alendronate treatment cessation, the ulcerations had completely epithelialized. In addition, the patient exhibited no clinical evidence of recurrence 4 months after withdrawing alendronate treatment. This outcome confirmed that other forms of treatment may be more suitable for patients who have difficulty in swallowing BP tablets.
