Delay of endoscopic submucosal dissection-induced gastric ulcer healing by methotrexate.

We report a case of methotrexate (MTX) delaying the healing of an endoscopic submucosal dissection (ESD)-induced gastric ulcer. The patient, who had been taking MTX for rheumatoid arthritis, underwent ESD for early gastric carcinoma. Despite taking vonoprazan after ESD, abdominal pain and anorexia continued, and the gastric ulcer did not heal after the ESD. After discontinuing MTX, the patient's symptoms improved and the ulcer healed. Patients taking MTX require careful follow-up after ESD, considering that ulcers can be difficult to heal. Discontinuation of MTX should be considered if delayed healing of an ulcer is observed.