How Often Should I Have a Colonoscopy? Colon cancer screening is a vital part of colon cancer prevention. In this video, Dr. Mark Kozloff explains when a person should first start getting colonoscopies and how often they should have them thereafter. Colon Cancer Answers is a social media show where viewers submit a question and get the answer from an expert. Submit your question now at, This information should not be relied upon as a substitute for personal medical advice, diagnosis or treatment. Use the information provided on this site solely at your own risk.