T3 and t4 may remain normal. Tsh being high indicates a signal that your thyroid gland is under stress. Especially so if your tsh is beyond 10. Free t3 and free t4 have higher significance in this regard then just total t3 and total t4. It is highly recommended that you keep on taking the medicines if you're already taking or you get tested for anti tpo to get the full picture before we start medicines.