I don't know if there is already a thread about this somewhere, but I just wanted to point out that hypothyroid often causes constipation, tiredness and weight gain. After the birth of my daughter I developped post-partum thyroiditis. Basically my body attacked my thyroid and sent it skyrocketing (hyperthyroid). I was having panic attack like episodes where I would feel dizzy, my heart would race and I felt like I couldn't breathe. My hair was falling out and I couldn't sleep. Then after 2 or so months of that, I went hypothyroid and was always tired, with NO energy to do anything. I imagine that is what it feels like to be depressed, but I didn't have quite the emotional component that comes with depression. I still felt joy, but was just so tired. Anyways, I have been on Synthroid now since Feb and things are starting to go back to normal.
I just wanted to tell people who have chronic constipation/tiredness etc. to request a thyroid function test. It's a very common test, and is usually one of the first things a Dr. thinks of when I pt. complains of tiredness, but you never know with those docs!
Hope this post helps someone! If you can find the underlying cause of the constipation, hopefully the problem will correct itself without all the meds/laxatives. Don't get me wrong they are TOTALLY necessary when trying to heal a fissure etc, but once that's done maybe they wouldn't be needed anymore! Wouldn't that be nice...oh to be normal again. LOL.

Great advice, thanks for posting!!!