Gastrointestinal Diseases Near Me Holistic Practioner Gastrointestinal Diseases near me in Ferndale, Michigan. Gastrointestinal Diseases (GI) affect the gastrointestinal (GI) tract from the mouth to the anus. There are two types: functional and structural. Some examples include nausea/vomiting, food poisoning, lactose intolerance, and diarrhea.