4 mos ago Iad a still-unexplained attack of hives, and same time to have a feeling of obstruction in my throat. Hives disappeared, but felt as though there was gas in my chest I couldn't get rid of. Drinking warm liquids helped temporarily: suddenly I would be able to belch -- felt like BBs coming out of esophagus. One day I regurgitated under this pressure, and spit out about 2 tbsp of dense white foam: no acid taste, no food, no smell -- just foam. Saliva is also full of bubbles; twice even vented gas bubbles from eurethra. Barium Swallow test: found no indication stomach or esophagus abnormality,no hiatal hernia, no indication reflux. Thyroid ultrasound showed only normal polyps. Blood panel normal. Then Sudafed for post nasal drip helped clear the foam by reducing mucus production: made clear that something is being generated IN my stomach or intestinal tract and venting upward (never down): still steadily venting gas (?) under pressure orally. FYI: NOT breath being pressed out of my lungs by extra internal pressure: can exhale completely, keeping mouth shut and not inhaling: within a few seconds there will be tasteless pressure up my throat and into my mouth that literally pops my lips open, & feeling of pressure in thorax/chest region diminishing. Doctor currently has me trying a PPI on assumption this all is somehow acid reflux anyway ... I am not seeing any good change at all. Whatever this is has no taste & no smell; can trigger regurgitation of foam or sometimes residue from upper stomach, but is not vomiting and usually doesn't include any food at all. Regularly in regurgitated foam or mucus a scatter of small mushy particles light tannish pink in color --- even when haven't eaten solid material for hours or days (often warm latte chai and yoghurt and soups are all I eat). Now lower abdomen is very tender two days now. WHAT OTHER POSSIBILITIES SHOULD I BE ASKING --- INSISTING --- MY DOCTOR LOOK INTO? Thankyou for your time.