Having a Colonoscopy is a very important thing to do to check for colon cancer and if caught soon enough the colon cancer can be removed and cured which will prevent death from the colon cancer.
The patient is sedated when a colonoscopy is performed but sometimes it can be painful if you're not sedated enough.
When I went into have a colonoscopy I did experience a little bit of pain during the colonoscopy procedure but the pain I went through wasn't very much and didn't last long and was well worth it to check for colon cancer which I thankfully didn't have.