you seem to be focusing on the esophagus and not the toxins in the system. If you're throwing up while drinking, its your body trying to reject those toxins because its too much for you too handle. Even if you could find a method that would allow you to "keep it down", you'd just be taking the damage directly to the liver and kidneys instead.

As far as I understand it at least, Birdgirl might be able to toss in some knowledge here, being the med student.

But I'd suggest you listen to her and just not set your heart on drinking to excess. Moderate yourself a little, you'll feel classier when you're not throwing up all over your shoes.