By: Dr. Geoffrey Modest
I ran across an article on the pathophysiology, diagnosis and treatment of excessive belching, which is a pretty common primary care issue, and I have mostly been treating it as a GERD symptom. But, of course, it is more complicated than that…. (see Am J Gastroenterol 2014; 109:1196–1203). It turns out that about 50% of the general population with dyspepsia report excessive belching. Use of manometric testing/impedance monitoring has shown that there are 2 mechanisms: the “gastric belch”, which is a vagally-mediated reflex with a relaxation of the LES (lower esophageal sphincter) and expulsion of gastric air, and a “supragastric belch” in which pharyngeal air is sucked into the esophagus when the diaphragm contracts and causes a negative intrathoracic pressure, then is quickly expelled before it reaches the stomach through relaxation of the UES (upper esophageal sphincter) and a closed glottis.
A few comments:
–Gastric belches: increases with carbonated beverages (no big surprise). happens on average 30 times/24 hours. Air distension in the stomach leads to relaxation of LES, then triggers second reflex relaxation of UES. involved neurotransmitters include GABA and the cannabinoid receptor-1.
–Supragastric belches: patients may be aware this is voluntary or not. the authors differentiate supragastric belching from aerophagia, which is swallowing of air and not usually identified by patients as belching, but abdominal bloating and distension. Supragastric belching is often diagnosed by lack of belching during speaking, is often a repetitive problem (vs gastric belching, where a large amount of air is expelled at one time), and is less frequent when the patient is distracted. Treatment is to explain the mechanism to the patient and the use of behavioral therapy, including speech therapy, practicing conventional breathing and vocal exercises.
–GERD: in setting of known GERD, 40-49% or patients have belching, and most are supragastric. Proton pump inhibitors (PPIs) do seem to help (confirming my experience). No study has looked at behavioral therapy in these patients. There are some patients with GERD where supragastric belches can induce reflux episodes.
So, more than you probably ever wanted to know about belching…. my sense is that if GERD is present, treat with meds (though I would start with calcium antacids, and augment as needed to H2-blockers, then PPIs). Probably also makes sense to try these even without clear GERD. and consider behavioral therapy, especially if nonresponsive to meds and the symptoms really bother the patient.