From what you have written, I understand that you take alcohol on an empty stomach. I would like you to know that alcohol irritates the lining of the stomach, which when severe, leads to bleeding from the stomach lining, manifesting as black stools. If the stomach is empty when alcohol is taken, the damage is more. Smoking
also causes gastritis
. So, the best possible option for you would be to consider quitting both smoking and alcohol, for which you may consult a psychiatrist
. In addition, you can consult a gastroenterologist
for assessment and management of the damage to stomach already done.
Hope this has been of help. Best wishes.