Rectal bleeding is never normal and should always be medically investigated. For possible causes google rectal bleeding and click on to one of the many websites. The Medicinenet pages are particularly informative.
regards
Morecambe
No I haven't eaten anything red.
I have been taking it on and off for a few months now.
and no hemmorhoids that I am aware of.
Welcome to the gastroenterology community! Did you just start taking prevacid? Have you eaten anything red recently? Are you constipated? Do you have hemmorhoids?