Gastritis is an acute and chronic inflammation of the gastric mucosa caused by various reasons. The most common types of gastritis are acute gastritis and chronic gastritis. The common symptoms of acute gastritis include upper abdominal pain, bloating, nausea, vomiting, and loss of appetite. Severe cases may experience vomiting blood, fever, dehydration, and even shock. Symptoms of chronic gastritis are not specific; many cases are asymptomatic. Those with symptoms may experience upper abdominal pain or discomfort, loss of appetite, belching, acid reflux, and nausea. Symptoms are often related to food intake, and a significant number of patients may not show any symptoms at all. Patients with gastric erosion may experience minor or major bleeding, and chronic minor bleeding can lead to iron deficiency anemia.