Gastroesophageal Reflux Disease (GERD): This is a common condition in older adults, characterized by stomach acid frequently flowing back into the tube connecting the mouth and stomach (esophagus). Symptoms include stomach pain, heartburn, and difficulty swallowing.

Peptic Ulcer Disease: This condition involves sores in the lining of the stomach or the first part of the small intestine, often caused by infection with the bacteria Helicobacter pylori or long-term use of anti-inflammatory drugs like ibuprofen. Symptoms include stomach pain, bloating, and nausea.
Gastritis: Inflammation of the stomach lining, which can be caused by infection, alcohol, or medications. Symptoms include stomach pain, nausea, and vomiting.
Functional Dyspepsia: A term for recurring signs and symptoms of indigestion that have no obvious cause. Symptoms include stomach pain, bloating, and early satiety.

Myocardial Infarction: Although more commonly associated with chest pain, myocardial infarction (heart attack) can sometimes present with epigastric discomfort or stomach pain, especially in women and diabetic patients.
Pancreatitis: Inflammation of the pancreas, which can cause severe stomach pain, nausea, and vomiting. It requires immediate medical attention.
Appendicitis: Although the pain typically starts near the navel and then moves to the lower right abdomen, some cases can present with upper abdominal or stomach pain, especially if the appendix is located higher than usual.
Mesenteric Ischemia: A condition where the blood flow to the intestines is blocked, leading to tissue death. It can present with severe stomach pain out of proportion to the physical examination findings.

Gastric Cancer: Although less common, stomach cancer can present with stomach pain, weight loss, and difficulty swallowing. It's more common in certain geographic areas and in individuals with a family history.
Zollinger-Ellison Syndrome: A rare disorder characterized by excessive gastric acid production due to a gastrin-producing tumor. Symptoms include severe stomach pain, diarrhea, and weight loss.
Eosinophilic Gastroenteritis: A rare condition characterized by the presence of eosinophils in the stomach wall, leading to inflammation and symptoms like stomach pain, nausea, and vomiting.