What should i expect when i go in for a colonoscopy? how painful/uncomfortable is it?

Colonoscopy: Colonoscopy may be done in a doctor's office, clinic, or a hospital. The test is most often done by a doctor who works with problems of the digestive system (gastroenterologist). Some family doctors, internists, and surgeons are also trained to do colonoscopy. During the test, you may get a pain medicine and a sedative put in a vein in your arm (iv). You many not remember anything about the test.