Thyroid medication and side effects

[cfromnc2012]

Approximately 1 week ago, I experienced dizziness, head fogginess, eye blurriness, eye pressure, being lethargic, confused and the list goes on.  I thought it was an eye problem.  I had my eyes examined for eye pressure as well as the optic nerve.  All were normal.  I realized that it was possible my thyroid levels could be off.  I scheduled a doctor's appointment on Monday and the results came back that I was at 8.5 and that I should be at 0.4 - 4.5.  The doctor increased my dosage from 0.112 to 0.125 today.  I will start the meds tomorrow morning.  My question is that why did it take so long and happen so quickly to experience these side effects when I've been on Levothyroxine for at least 8 months?  I was diagnosed with Graves Disease in 2002 and even with my dosages changing a little bit over the last 10 years, this is the first time it hit me like this. I thought I was going to have a stroke or a heart attack.  Has this happened to anyone before?

[cfromnc2012]

Thank you so much for your input.  For a while I thought I was going crazy.

[goolarra]

These are not really side effects of the levo.  You were undermedicated, which made you become hypo again.  The symptoms you list are symptoms of hypo.  

There are many reasons why our requirements of thyroid hormone might change...stress, trauma, sickness, surgery, aging, weight changes (big ones), general health, just to name a few.

It probably didn't happen as quickly as you thought it did.  Your FT3 and FT4 levels were probably falling for a while...it takes some time before they get low enough for symptoms to set in.  Does your doctor test FT3 and FT4 as well?  They are much more important than TSH.  If he's been testing those, you might have seen a pattern of falling levels before symptoms set in.