An anesthesiologist is someone who anesthetizes patients. They can help sedate patients and put them under for surgeries or other medical procedures. They help prepare their patients for procedures and make sure they are not experiencing any pain or fear associated with the treatment or procedure they are undergoing. They work closely with other doctors, surgeons, and specialists to ensure that patients are being treated properly.

A gastroenterologist is a healthcare professional who has been educated and trained to treat patients who are experiencing health problems or have diseases that affect the gastrointestinal tract and liver. They also diagnose and treat diseases that affect the esophagus, stomach, small intestine, colon, rectum, pancreas, gallbladder, bile ducts, and liver.

An internist or Internal Medicine doctor is someone who specializes in diagnosing and treating illnesses, diseases, and health problems. Most internists are also primary care doctors and treat patients on a regular basis. They can diagnose and treat common illnesses or more serious problems. Most people see an internist regularly. Those with chronic illnesses may do so on a monthly or even weekly basis. Internists are the most common types of doctors.