This is a question on behalf of my friend. She was diagnosed hypo just over a year ago. After trying Levo, then went on to levo/T3, then T3 - but only a low dose, 20mcg twice a day. Now she thinks the T3 has caused weak muscles and ligaments because she's got a bad back (has aggravated an old injury.) Personally, I don't think it does, but what do I know! Oh, she has a low ferritin of 28, folate is 10, B12 386. She's taking a 5mg Spatone sachet a day but 'thinks' it's causing an uncomfortable feeling and bloating around her middle... The B12 supplement is apparently giving her the runs so on those days she doesn't take one.