What happens at a colonoscopy?
Last updated September 3, 2026.
You are sedated while a thin flexible camera examines your entire colon - and polyps found along the way are removed in the same session. That removal is how colonoscopy prevents cancer rather than only finding it. The procedure takes well under an hour, you remember little or nothing, and you need a ride home because the sedatives take hours to wear off. The prep the day before is the hard part, not the procedure.
What to do
- Treat the prep instructions as exact. A clear-liquid diet plus the prep solution; a clean colon is what makes the exam accurate.
- Arrange the ride home first. Sedation rules out driving for the rest of the day.
- Review your medications ahead. Blood thinners and diabetes drugs often need adjusted instructions - ask a week out.
- Expect grogginess and bloating after. Both pass within hours; most people eat normally the same day.
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