Gastritis is a condition in which inflammation is caused in the inner lining of the stomach due to the excessive production of HCL and digestive enzymes. Symptoms Some of the commonly observed symptoms include,loss of appetite,nausea,vomiting,etc. In more chronic cases the patient experiences heartburn. Root causes Gastritis may be caused due to the production of excessive amounts of acid in the stomach,a bacterial infection in the stomach or the use of pain killers.In some instances it may also be caused due to stress.