It gets better and better with proper thyroid treatment. Before treatment, I was so constipated with acid indigestion.
When the T4 started getting into my system, I had several bowel movements in a day at first. This is mostly because it gets quite packed in the intestines for awhile, and it all wants to come out.
Now since being on proper treatment, I have a bowel movement in about 10 minutes from awakening in the morning. It is not a small one either.