Hi Dear, Welcome to Health Care Magic Team. Understanding concern about your health. Back pain as per your query after alcohol consumption occur only if a you have alcohol dependency or it could be after alcohol abuse. Otherwise mainly stomach pain occurs because of a condition called pancreatitis. Drinking small quantity of alcohol does not effect kidney much but when large amount is taken kidneys are forced to work out quiet harder as compare to normal one which start causing too much urination and leads to dehydration. It in turn affect liver as well. I would suggest you to avoid large quantity of alcohol at a single stretch. Whenever you are taking alcohol take it with large amount of water or fruit juices so that body remain re hydrated. If your symptoms keeps on persisting and your feel pressure in lungs along with back or too much pain then visit gastroenterlogist nearby you as that could be because of certain systemic diseases like Hodgkins Lymphoma. Hope your concern has been resolved. Get Well Soon. Best Wishes, Dr. Harry Maheshwari