I have had gastric bypass surgery. Is it safe to have a colonoscopy?

I have had gastric bypass surgery. Is it safe to have a colonoscopy?
Usually, gastric bypass involves decreasing the stomach size and then diverting food past the first portion of the small intestine.
In a colonoscopy, the scope is passed into the rectum and directed through the large intestine until it reaches the junction between large and small intestines. It will never reach to the point of the bypass.
So, it is likely quite safe for you to have the colonoscopy, but the doctor performing it will probably want to confirm the exact anatomy of your bypass before hand just to make sure.
I would think that would be something to ask the doctor before he performs the colonoscopy