Thank you for the query.
It all depends of how old are you. If you are older than 50, colon cancer
should be ruled out at first. If you are younger person, hemorrhoids are most probable reason of bright red blood in the stool. With hemorrhoids, blood is always on the surface of the stool. If your blood is mixed with the stool, the reason is much more serious than hemorrhoids.Weight loss
and loss of appetite are very concerning symptoms. That is why I suggest you to visit your doctor, have rectal examination
, blood work and colonoscopy
Hope this will help.