For banded patients:The reason you are not to drink is the following: You have swallowed something that is stuck on top of the band. It is effectively covering up the hole that it needs to go in to get to the bottom part of the stomach. Once food you eat gets to the bottom part of your stomach, you have no pain, are not stuck, do not PB or slime and although you may eventually feel full like you did when you ate too much pre banding, it will not make you feel pain. This is how you can "eat around the band". If you eat chocolate, shakes, etc, the melted/liquid will slip down past the band, go into the bottom of the stomach, you won't feel like you need to stop and you could absorb a lot of calories that way.
Okay, so you ate something that covered this hole, or the hole is too small for much of any food to go through (as in a too tight fill). (this especially happens if you do not cut your food into eraser sized pieces, mixed it with something wet, not chewed 20-30 times until it is like baby food in your mouth, swallowed too big a wad of baby food (which is why you cut it up into little pieces so that you won't have too much in your mouth when you go to swallow). You can not swallow, cannot burp. The food is now acting like a cork in a bottle. IF YOU DRINK ANYTHING you just make what is stuck pack down over the hole, therefore making it worse. If you stop trying to eat or drink anything the minute you feel anything different than no feeling, DO NOT TAKE ANOTHER BITE, do not chew another bite thinking the one that is starting to struggle getting through will go through, and DO NOT drink ANYTHING, because it probably will not go through in time and the small feeling of discomfort will only become worse the more bites you take. STOP eating and WAIT. Wait until you feel back to normal. This can take a lot of minutes. Wait.