I was, originally, started out on Synthroid and didn't do well on it, but I really believe that had as much (or more) to do with the prescribing doctor as it had to do with the medication. Once I began going to my endo, I was switched over to generic levothyroxine for cost effectiveness. I did fine on levo, but when Tirosint came on the market, I chose to try it (and pay the extra cost), since I do have known absorption issues.