I'm not sure if this helps, but I was the same- they'd increase then reduce it. So the last visit to the hospital (years ago) I refused to reduce it. Had a lot of consultants coming into the room, when finally a lady consultant said how often do you miss taking it each week. I said a couple of days, especially when it's on the lower dose because I fall asleep before I get chance to take it i'm so tired. She left me on the higher dose.
Then 2 babies later (I now have 4!) I have seeked help from this brilliant site and all the lovely people here.
I've taken ferritin, folate, b12 and increased my dose further until I have felt well. I have now been on 200 mcg for 2 years and can honestly say I have just started to feel like I don't have anything wrong with me. My last bloods were 0.01 and T4 16. The doctors have no idea i've upped the dose, and say i'm on the correct amount! I don't bother to tell them, worry a little each time I have to have my routine bloods done in case they tell me there prescribed dose is too high but i'd just tell them i've been on a higher dose and i'll reduce that a little.
I'm not advising self medication. But i've suffered for 12 years, and only the last 2 have I felt normal.