Zollinger-Ellison syndrome is a rare condition characterized by the formation of tumors called gastrinomas, which usually develop in the pancreas or the duodenum. These tumors produce excessive amounts of the hormone gastrin, leading to increased stomach acid production. This can cause severe peptic ulcers and gastrointestinal symptoms like abdominal pain and diarrhea. Diagnosis often involves measuring gastrin levels in the blood and imaging tests to locate the tumors. Treatment may include medications to reduce stomach acid, such as proton pump inhibitors, and surgery to remove the gastrinomas if possible. Early detection and management are crucial for improving outcomes.