Which concern would prompt the nurse to contact the health care provider when a client with gastric ulcers receives a prescription for ranitidine 150 mg twice a day? A. Ranitidine can increase the risk for gastrointestinal bleeding. B. An administration route is not specified. C. Ranitidine is contraindicated for gastric ulcers. D. Ranitidine should be given with an adjuvant.