Capsule endoscopy is primarily used to investigate the cause of unexplained gastrointestinal bleeding and to diagnose inflammatory bowel diseases affecting the small intestine, such as Crohn's disease. Furthermore, it is an effective method for investigating conditions accompanied by symptoms like unexplained iron deficiency anemia, chronic diarrhea, abdominal pain, and weight loss, and for the diagnosis of polyps or tumors in the small intestine.