Hey Dany...I know this is an old forum but I just found this by googling synthroid and dizziness. I just wanted to see how you were doing or if you stopped the synthroid and started the armour? Our stories are very much the same...but all my numbers are normal but my B12 is always high 1200 or more, so they sent me for an ultra sound and found 2 small non active nodules one on each side of my thyroid so they put me on levothyroxine 25mcg after a week I started feeling great then I started getting hyper they switched me to armour 30 and I got very sick again so endo changed it to armour 15 after 2 days of taking it I was sicker!So they stopped it for 6 weeks now im on brand synthroid 12.5 mcg and again in dizzy fatigued depressed I cry all the time I cant go out hardly anywhere like shopping I get so dizzy I have to leave!I cant drive red lights make me feel like im on a boat then I have severe anxiety and panic attacks.All this started in January 2013 here it is October and im still suffering I have no life!I had to quit my job that I loved I worked as a pharmacy technician at the same place for 9 years but my drive was 45 minutes each way and lots of stop lights I couldn't function at work with all the panic attacks I took a 3 month leave and tried to go back even cut back to part time I just couldn't do it .I feel my life is over ill never get better ive been to over 20 doctors and the er twice with no help they send me home saying its just a panic attack!My body is trying to tell me something the DR.s here cant figure it out.Its not my ears ive been to vestibular testing they did lots of test all negative mri and ct scan of brain clear,hyda scan clear,i had sctratch test allergy testing all negative, eeg was negative,sleep study negative said they suspect nocturnal panic attacks.I go this week for asthma test since my sister has it bad I don't think I have it tho I don't wheeze I just have shortness of breath and next week I go to gastro dr I had a blood test done that exposed glutin intolerance and egg white allergy ?Ive been gluten free for 4 days so far im trying so hard to get my life back,sorry to be so long im just trying to reach out to someone who has been through this and may have some advice.Thank you.Sheila PS. antibodies are negative