I have been taking Levo now for over 20 years and always had symptoms. Begged my doctor for combo meds which I tried for 3 months but didn't feel any different. I cut out T4 altogether and just started taking 20mg of T3 daily. All the irritating symptoms disappeared and I've never felt better (the fibromyalgia went away as well!!!!) - but!! My cholesterol has gone up again to 5.84 (I have arterschlerosis so doctor prescribed Repatha). My TSH has gone up to 6.42 Free T4 down to 7.4, Free T3 is 3.76 and thyroglobulin AK up to 126. I don't understand any of these numbers but am still feeling great. If I don't take or only take half of the T3 I go back to how I was before.