Causes of an upset stomach include smoking, anxiety, too much caffeine and overeating, especially fatty or spicy foods, states Mayo Clinic. Other causes include an inability to digest dairy products, stomach ulcers, swallowed air and stomach cancer, notes WebMD.
An upset stomach is discomfort in the upper abdomen and involves symptoms of abdominal pain and a feeling of fullness after a person starts eating, explains Mayo Clinic. Food, drinks or medication may trigger this condition, such as eating too quickly, drinking alcohol or carbonated beverages, and consuming pain relievers and iron supplements. Conditions such as peptic ulcers, gallstones, constipation and insufficient flow of blood to the intestine can also cause an upset stomach.
Symptoms of an upset stomach include nausea, bloating in the upper abdomen, a fullness that lasts longer than it should, heartburn and severe pain in the area between the navel and the bottom of the breastbone, reports Mayo Clinic. Patients with severe abdominal pain accompanied by loss of appetite, tarry stools, weakness or trouble swallowing should seek medical attention.
During diagnosis, doctors ask patients about the symptoms and medical history, and examine the stomach and chest, explains Medicine News Today. Tests include endoscopy to examine the abdomen in details, X-rays, abdominal computed tomography and abdominal ultrasound, which involves viewing the inside of the abdomen on a monitor.