after eating pizza is not surprising at all, and though this pain can be termed acid reflux
, heartburn, or indigestion they are not all the same. Acid reflux is caused by the incomplete closure of the muscular connection between the esophagus and the stomach. This allows acid to travel out of the stomach, where it generally does not cause damage thanks to an acid-proof lining, into the esophagus, which does not have this special lining, where it can erode the lining and cause pain. Heartburn or indigestion is generally given the medical term dyspepsia and can result from a stomach or intestinal ulcer.
Though everyone is different, there are a number of foods that are especially prone to causing acid reflux and dyspepsia. Among these the most common are coffee, chocolate and alcohol. However, as you note in your case foods with a high acid content such as tomatoes that are in pizza sauce and citrus fruits can also cause this sensation. In addition, fatty foods help decrease the tone of the muscle that protects the connection between the stomach and esophagus. When you eat a meal with high acid and high fat like pizza this is a perfect combination to cause reflux symptoms as the fat from the cheese in the pizza decreases the tone while the high acid from the sauce combines with high stomach acid and travels back up the esophagus.
Taking antacids can help, but the most important thing you can do is create a small log of the foods that cause your symptoms and then avoid them as much as possible. Talk to your primary care physician
, who can best evaluate your symptoms and discuss your options. Good luck!