Levothyroxine, Levoxyl, Synthroid, Levothroid, Unithroid... They're all the exact same chemical agent. Only the name on the label and the tablet binders/fillers are different. Which one works best for you is a matter of trial and error. Maybe the levoT "sent you to the moon", but it appears the Levoxyl isn't doing enough. How long have you been taking it, and in what dose? It could be you're expecting too much too soon. It takes time for a dose to reach full effectiveness ... at least 6 weeks. And it generally takes several dose increases over the course of 6 months or more before you feel totally yourself. Doctors never tell you these things, but it's a matter of general agreement among us in the trenches.

Educate yourself about the best ways to treat hypoT. Make yourself understand what a thyroid gland's job is and what happens to your body when it can't do it. If you understand these things and learn all the terminology involved so that you can ask the right questions, you're almost guaranteed to have a better outcome than if you leave the whole business up to the MD's discretion.