Question: What is the cause of and how can I treat uncontrollable belching?
Dr. Hibberd's Answer:

Belching (called eructation in medical lingo) usually occurs from swallowed air. Carbonated gas drinks are the most common cause. Some of us have excessive salivation, and as a result, swallow more air than usual. Most of our swallowed air does not pass though the bowel, but is belched up (eructated).
Poorly fitting dentures, gum chewing, nausea, and GERD, are common causes of increased salivation, resulting in "burps." Antacids may also cause belching. Of course, smoking while eating or drinking will also produce swallowed air. Belching is rarely a sign of major disease, but when persistent should be investigated. Older patients may merit a cardiac as well as gastro-intestinal evaluation if belching is not corrected by dietary changes.