In patients who show signs of bleeding and bleeding after polypectomy such as EMR and ESD for polyps with a diameter of 2 cm or more in the lower gastrointestinal tract, the effectiveness and safety of Nexpowder as an endoscopic hemostatic treatment are confirmed.

Total number of target subjects 66 Test group 33 / Control group: 33 If endoscopic polypectomy is performed on polyps of 2cm or more, the probability of bleeding as a complication is 6.5%. This clinical study is an observational study to confirm the safety and effectiveness of Nexpowder, an endoscopic hemostatic powder after colonoscopy polypectomy, and an exploratory evaluation of 60 patients is conducted.

Inclusion Criteria:

1. Adult volunteers aged 19 or older during screening
2. A person who is scheduled to perform polypectomy for polyps with a diameter of 2 cm or more, such as Endoscopic Mucosal Resection (EMR) or Endoscopic Submucosal Dissection (ESD)
3. If the researcher agrees to voluntarily participate in the clinical study and determines that the subject cannot voluntarily consent due to the elderly aged 80 or older or other emergency situations, a written consent of the subject's legal representative is required

Exclusion Criteria:

1. Upper gastrointestinal bleeding
2. If ulcerative bleeding is not caused by the procedure
3. If you are suffering from a blood clotting disorder
4. Aspirin and anticoagulant medications cannot be discontinued
5. Pregnant or lactating
6. Where colonoscopy is prohibited due to comorbid diseases, etc
7. If the bleeding area cannot be identified or the bleeding area cannot be reached with an endoscope
8. If you have participated in a relevant clinical trial that may affect the results of this study within the last one month
9. Those with genetic problems such as galactose intolerance, Lapp lactase deficiency, or glucose galactose malabsorption
10. A person who is hypersensitive to food additive Blue No. 1 or has a history of allergies
11. In the case where the researcher determines that it is inappropriate to participate in clinical trials due to other reasons other than the above selection exclusion criteria