Hello Dr. Rynne. I work at a Drug and Alcohol treatment centre and one of our clients has been sick and vomiting sporadically since about 1 am Tuesday morning. He seemed to be better this morning, able to eat both breakfast and lunch without issue, but suddenly late this afternoon he started vomiting again. He says his stomach is very distended and he feels very bloated. What might be causing this? the pain is central on his abdomen, so I have ruled out appendicitis.