It basically is slowed emptying of the
stomach (usually due to nerve damage) and it causes
bloating,
pain, nausea and vomiting. The causes of it are many and it is dxd on a gastric emptying scan in nuclear medicine. Sometimes it comes on after a bad viral or bacterial GI infection and is either transient or becomes a permanent condition, and sometimes it is linked to a neurologic and/or autoimmune disease (diabetes, lupus, scleroderma, thyroid disease, etc.).