 [ Symptoms ] what is the difference between liothyronine and levothyroxine  i have just completed a thyroid removal and a radiation treatment prior to the radiation i was on liothyronine and now i have been put on levothyroxine this new med makes me nauseous [ Disease ] hi have a good read through this link from webmd covers your problem <link> as for the nausea its a side effect hope this helps you good luck