Hypo for 4 years and now Hyper?

[ThyroidMania]

My doctor first noticed my enlarged thyroid around 4 years ago.  I saw an endo and she started doing bloodwork and also noticed I had hypothyroidism.  I started off taking .25 mcg of levo, and I have steadily increased my dosage until about 9 months ago to 100 mcg. 3 months ago I got bloodwork done and my thryoid levels were finally back to normal.  I went in for a check up with more bloodwork done, and got the results today.  All of a sudden, my levels have DOUBLED, and I now have symptoms of hyperthyroidism.  I have lost 7 pounds in three months, and I was even given medicine to slow down my heart.  My doctor told me I must stop taking my levo all together.  I am nervous about doing this as I have been on some dosage for several years now.  Has anyone ever had this happen to them?  If so, why would this happen?  Even though I have been on the 100 mcg dosage for less than a year, before that I was on 75, so it isn't too much of a difference.  I am going to start getting bloodwork done weekly, but I am wondering what the likelihood is that this is the result of having too high a dose of hormone, or if my thyroid is just going crazy.  Any thoughts?

[helen1207]

do you know the cause of being hypo? did you check anti-body? if you have hashimoto's, then you might experience the swing in between hypo and hyper, it might not necessarily because of the dose. that's what i learn from my own experience. i am still trying to figure out how to deal with that. but i think you should at least try to find out why you are hypo?

[chigirl29]

Probably a dosing issue.  I think that is my problem right now.  

[blitzerdog]

Same problem as you. I have been on synthroid stopped that after 2 years and then I was on proplythiour and stopped that after 2 years. Both times I was at fixed doses. Now I'm going to do the RAI 131 and knock out the thyroid and get it over with. It's been a tough time for me, I feel depressed and what not but you just have to be strong about it. My mom and aunt take synthroid and so it's very common in my family.