Tirosint is a newer thyroid medication which is similar but much different than levothyroxine. While both medications may contain the same active ingredient they differ in their inactive ingredients and this may make all the difference! There have been many reported case studies of people who switch from levothyroxine to Tirosint who suddenly feel much better. In this article, you will learn exactly why this happens and why Tirosint may be the best T4 only thyroid medication on the market.