I think Synthroid brought on AF!

wina · 09-07-2004, 03:20 PM

This is too weird, after a year of having hypo symptoms but lab results leaning toward the hyper end of normal, a few weeks ago my free T3 tested low and doc put me on Synthroid 25 mcg. 3 days later I had a full AF that lasted 4 days (first time in 2 years!!) The strange thing is I was on week 3 of BCP. I think it's got to be the Synthroid because nothing else has changed. Other than that though I still feel like crap and gaining weight fast. Today doc upped my dosage to 50 mcg, maybe that will help. I'm so tired of feeling lousy.

Also, a question...

If free T4 and TSH are normal and free T3 is low, does that indicate that my body isn't converting T4 into T3 as it should? If i understand correctly, Synthroid is T4 and has to be converted into T3. So if I'm not converting my own T4 into T3 what good does adding more T4 (Synthroid) do? Maybe I'm oversimplifying but this doesn't make sense to me.

Here are my lab results from a few weeks ago:

Free T4: 1.1 mg/dl
TSH: 1.48 miu/l
Free T3: 169 pg/dl

Wiggleynose · 09-08-2004, 07:59 PM

Well hypothyroid does affect our AF so it's possible that synthroid did it but it could also be the BCP. The first two months I was on bcp I had early AF.

You are on the right track with the T4/T3 conversion. If your T3 is low and your T4 is high/normal you might not be converting it properly to t3.

I think if you get a raise in dose of synthroid again and still don't feel better you might want to talk to your doctor about getting a T3 supplement or taking something like Armour Thyroid that has T4 and T3 in it.

I'm currently taking Armour and was feeling better almost immediately. Just recently did he give me a little boost in my dose to compensate for my increase in my workout regimine.

Good luck and I hope you feel better with this new, higher dose!

bectaz · 09-26-2004, 06:27 PM

I have very little nice to say about Synthroid (other than their drug reps do a very good job promoting the product)

I lost half my hair and felt absolutely horrible on that drug.

I did a lot of research and found a doc that would RX Armour - - i feel better than I have in ten years.

If you haven't checked out the about.com thyroid forum - it's excellent.

And yes - i think you're right on in terms of your body not converting to T3.

at a minimum, I'd say you need a new drug added like Cytomel.

I'm really impressed with Armour though - and my new doc - - who had never RX'd it before - is pretty sold on it too - - it has truly been a miracle for me.