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252327 tn?1250187576

my doctor added cytomel / synthriod

I have been taking 112mcg synthroid for 3 yrs now, I have pretty much crossed over to hyper, my tsh is 0.037,  T4 13.1
my t3 free  is  low 2.7,   free t 4  1.83 . Seems like my body isn't converting my t4 into t3,  So today my doctor added cytomel 25mcg, should he have lowered my dose of synthroid? Is it ok to take the same dose with cytomel? I have hypothyroidsim and hashimotos.
49 Responses
590177 tn?1288429454
My doctor lowered my dose of T4 when he added T3. From what I've read, it should be lowered.
280485 tn?1249017444
I can't remember the exact conversion but I think the conversion rate is something like 25mcg of T4 to 5mcg's of T3.  If it's not that, it something close.  And yes he should have lowered your T4 if you're somewhat hyper right now.  25mcg's of cytomel is a lot to add to your existing dosage.  

I take 10mcgs every morning, but in addition to 175 of Levothyroxine that I take at night.  Just to give you an idea, I was taking 200mcg of T4 when I took just T4 on it's own.  Please call and double check b4 taking this combo.

I will say that I don't now, nor have I ever, had Hashimotos, so it's not my area of expertise.  But this dosage of meds would definately make you more hyper than you currently are.
393685 tn?1425816122
He may not be looking at the TSH right now and tweeking your meds to adjust the Free T3's

When are you testing again? Is he spreading out the Cytomel through the day?

I believe your doctor is looking at to see if your conversion values are messed up. Are you still symptomatic of hypothyroidism symptoms with that low of a TSH?

252327 tn?1250187576
I am going to take my labs tomorrow so I get a definate baseline. those labs were done mid december. I was still having symptoms fatique, brain fog and terrible joint pain., plus palpuations.At one point they had boosted me up to 125mcg and it caused shortness of breath probably because it was took much t4 and my body was not converting it.
I took 100mcg of synthroid this at 6am this morning. At 9 am I took cytomel BUT I cut the pill in quarters and only took one quarter. It has only been about a hour, I seem to have more energy already but maybe its in my head.
451191 tn?1264436490
Dr. Lupo said yesterday to reduce Synthroid or Levo by 25 for every 25 of Cytomel that you add.  You are lucky.  My Endo won't prescribe it.  Says it's not good for cancer management :(
280485 tn?1249017444
I have to strongly disagree with your (ok, supposedly from Dr. Lupo's statement) conversion of T3 to T4 dosage as 1 to 1 (or 25mcg Cytomel to 25mcg of Levo/Synthroid). Maybe this was a typo or perhaps a misunderstanding on your part??  I went back and looked for where he could have possibly said such a crazy thing (as I missed this thread live), and the only referance I found was this:


I've been all over the map on my Cytomel to T4 dosage, so I've had some experience with this topic.  I stated earlier on this thread that I thought my doc had said it was something like 25 to 5, Levo to Cytomel.  Also for an alternate resource, here's the URL for the Armour site where they give a conversion table, albeit an approximation.  

http:// www .armourthyroid.com/con_faqs.aspx

I know everyone is effected differently by Cytomel as it is a function of how their specific body converts T4 into T3 and whether or not there is a conversion problem in that individual to begin with.  However... I don't think ANY website or doctor would give a 1 to 1 ratio of T4 to T3 as a conversion table.  

Case in point, After my TT, I was put on 25mcg's of Cytomel per day which was insufficient for me to function correctly.  I was changed to 50mcg per day which was a little high, but worked.  After RAI and trying several combo dosages (which I've since gone back to) I did try T4 alone and my dosage was 200mcg's.  If I went on 200mcg's of Cytomel, I'd be DEAD!  I was taking 137 of Levothyroxine when I was taking 25 of Cytomel.  It reduces your dosage by that much!

Also Shannon, did your doctor add anything to that "It's not good for Cancer management" statement?  I've never heard of that.  I can't imagine a senario where it would be a negative, as any combo suppresses TSH which is the necessary component in the equation.

How are you feeling?  Did you call the doctor?  Do you have lab reference ranges for your free T's?  At a TSH of .037, 25mcg's of Cytomel is TOO MUCH to "just add" to your existing dosage of T4!  Please call back and check with your doc as some of your symptoms can reflect a hyper-thyroid state as well as hypo.
451191 tn?1264436490
Whoooopsie, I misread Dr. Lupo's comment, that is the one I was referring to.  Sorry Charlie :)

My Endo basically told me that Cytomel messes with the TSH readings (which can effect the Tg readings) so that you are not getting an accurate number.  I wish he believed otherwise BELIEVE ME.  Obviously, he was referring to those that CAN convert the T4 in Synthroid into T3.  Since I'm so early on in my case, we don't believe that I am having trouble converting, it's just a matter of me being able to tolerate being hyperthyroid which makes me tired, irritable, etc. etc.

Sorry to get you all riled up :)
280485 tn?1249017444
K, so not really "riled up", but I was and am very concerned about Blondiee028.  I didn't want her to be mislead and think the additional 25 of Cytomel was A-OK and gulp it down...  then feel like cr@p.  I truely think this needs further investigation by her and doc.  I think he may just have had other things on his mind and forgotten to lower her dosage of T4.  Any way you slice it, she will be "hyper" as a kite if she swallows that script.  I don't think I would have gotten so "riled up" if she'd been perscribed a 5mcg dose to gulp down with that TSH, but 25mcg's is A LOT!  And a typo like that one to one conversion rate, could have her in the hospital lickity-split.  Thus the "riled up" clerification.

As for the cancer supression thing, I'd get another opinion if I were you and you still feel bad.  I go to what I consider, the top endo in Seattle.  Ever since my TT, he's almost pushed the Cytomel on me.  I mentioned above that I did try T4 alone... That was at my request!  After trying several combos of T4/T3, I just wanted to try T4 alone and see what would happen.  I didn't like it.  He would have never perscribed T4 by itself if I hadn't pushed him into it.  I have subsequently reverted to his way of thinking and accepted the Cytomel back into the equation.  At a reduced (for me) Cytomel dosage.  Good luck.
451191 tn?1264436490
My apologies to you and to Blondie :(  I thought I was helping and I just typed too fast.  It sounds like she has some really good advice from you since you have so much experience with this topic.

As for my Endo, I trust him implicitly.  If it gets to a point where I have to tell him that I want/need the Cytomel and he won't prescribe it, then I won't hesitate to find someone else.  At this point we are still dealing with my detectable Tg and I want to get that all squared away before I start adding any additional medication.  I definitely felt better on Cyto (I was on it after my TT) but I also had quite a bit of remnant thyroid tissue at the time, so it's hard for me to know what was the Cyto and what was regular old Thyroid hormone from my actual thyroid, you know?

Anyway, thank you for your experience, strength and hope.  I apologize if my comment seemed flippant, was just trying to make light...
280485 tn?1249017444
I just have to say that in re-reading my answer to you... I re-iterated "riled up" no less than three times!  Ugh!  Sorry.  I didn't mean to make you uncomfortable, nor did I take offense to or consider anything you said, flippant.  You usually have great advice and I am by no means, the expert here.  I've just tried all ranges of Cytomel and consider myself pretty well versed.  I knew it was a typo, but wanted to clerify for Blondee's sake.

But I do wonder about the Tg you're still getting...  Have you had that second scan yet or still on LID?  And if you see your doc soon could you ask for a clerification about the Tg and Cytomel thing?  I'd love to have more info on it.  After my last scan (which was clean btw...), as it has always been, my Tg was <0.1.  But I've almost always been on some dosage of Cytomel.  It'd be great to have some more info as I don't see my doc for another couple of months with that clean scan under my belt.
252327 tn?1250187576
I really appreciate all your help today,
I took the 100 mcg ,( at 6am) which was 12 mcg less than what I was taking. I took the 25mcg cytomel and cut it in quarters . I took the tiniest quarter at 9am.  I felt of kinda had a boost of energy for a few hours and it made my mind sharper. no palputations, no shortness of breath and not fatigued at all. I am going to take my blood in the morning and will have the results early the next morning. I am only going to take the quater of pill for a while.  My doc was out of town when he called this in for me , I have to touch base with him and recheck this dosage. Thanks to you guys here because I was going to take the whole dose in the am synthroid something told me to check online first.
Its 4;30 pm here and I am fine. I will probably do the same thing tomorrow. I will keep you posted. The board is the greatest!
252327 tn?1250187576
I did my labs today and will get results tomorrow. BUT I did go over the phone message with my doctor. He sent me a text message, I told him that he knew my t4's were running high  ( hyper now) but it seems like my body is not converting it into t3's. (still low) Therefore I am hyper and hypo at the same time.  I told him I read about cytomel and asked him what he thought about it. HE SAID HE TAKES IT HIMSELF . He told me to lower my dosage to 100 mcg.and add the 25 mcg of cytomel Then I asked him again do I stop the synthroid ? he said NO you take them together! Maybe cytomel is only t3? I am still scared and taking only 1/4 of the pill.  Advise is appreciated
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