Low TSH, Low FT4 & FT3

[Josiecatgrl]

Hello. I finally got to see an endo in February. He switched me from generic levothyroxine to Synthroid and added Cytomel. This helped a lot at first. The Cytomel is wonderful, but it wears off quickly. Lately I've been having horrible hypo symptoms again. I was diagnosed with hypothyroidism in Oct. 2010. Here are my labs:

10-11-10
TSH: 6.88
FT4 1.3 ((0.8-1.8)
FT3 2.7 (2.3-4.2)

Began treatment w/ 50 mcg levothyroxine

A little better, but still quite symptomatic

12-15-10

TSH 0.93
FT4 1.4 (0.8-1.8)
FT3 2.9 (2.3-4.2)

Increased levo dose, alternating 50 mcg w/ 75 mcg. Helped more, but still having symptoms

2-4-11  New appt. w/ Endo

TSH 1.78
FT4 1.9 (0.8-1.8)
FT3 2.9 (2.3-4.2)

Endo changed levo to brand Synthroid (same dosage 50/75) added Cytomel 5 mcg taken twice daily (total of 10 mcg a day. At first this helped A LOT.
Went back last week for labs. Been feeling bad again for last 3 weeks or so.
TSH 0.05
FT4 1.1 (0.8-1.8)
FT3 2.8 (2.3-4.2)

As you can see, my TSH is almost undetectable, but my FT4 has fallen A LOT & my FT3 fell a tiny bit, even with Cytomel! I am feeling almost as bad as before I was taking any meds at all! Endo is keeping my Synthroid dosage the same, but is increasing the Cytomel to 5 mcg taken 3 times a day. I'm wondering if  my Synthroid dose needs to increase too. I'm guessing that my TSH is almost meaningless at this point. I have NO hyper symptoms at all. I still have a low/normal heart rate, blood pressure, etc. In fact I feel hypo and am achy and want to sleep all the time.
I have no idea why my TSH is sooo low & my Frees haven't come up. Why is my FT3 still so low & why did my FT4 drop so much????
Please, does anyone have any insight as to what is going on??? Has my body gone crazy??

[Josiecatgrl]

Thank you! I didn't know it could take so long for FT3 to rise - that's good to know & now I'll be more patient. I'm also starting to think it might be the Synthroid since I seemed to be okay on the generic. I have some of the generic left and I think I'll go back on it for a few weeks to see if that helps. If so, I'll ask my endo if I can make a permanent switch off of Synthroid. I'll definitely check out the Tirosint!

[Barb135]

I don't think your FT levels dropped because of the addition of cytomel. Not everyone does well on Synthroid; I didn't........... I was started out on Synthroid, but when I started seeing my endo, he said generic levo was fine, and I actually did better on it. In addition, some people have issues with the fillers/binders and may not absorb the med as well as others.

Yes, your symptoms will worsen when your FT levels go down; however, the drop from 2.9 to 2.8 in your FT3 is really very insignificant.  Even though cytomel works fast and is used up quickly, it still takes time for labs to show an increase. I was on it for over a year before my FT3 even got to mid range.  Most people find that FT3 correlates best with symptoms, and with yours being in the low end of the range, it's not surprising that you have symptoms.

As I said earlier, most of us on cytomel, or other T3 med, have suppressed TSH; it's not a concern as long as you don't have hyper symptoms or labs.

I am currently on Tirosint, which is a new T4 gel cap that came out in May of last year.  I've been on it since August 2010, and I love it.  Being a gel cap, Tirosint has no fillers/binders, so it's hypoallergenic, it dissolves more readily and is more easily absorbed.  You might ask your doctor if you can try it.

[Josiecatgrl]

Hi :) I have been tested for B12 deficiency & my levels were actually quite good. I am on an iron supplement for anemia, which was severe back in October because my periods were so long and heavy. My ferritin is still on the low side, but has improved. I have not been tested for deficiencies of Vit. D, calcium, selenium or magnesium. However, I do take supplements for those minerals
I do have Hashimoto's. I'm guessing that over time my own thyroid function will continue to decline.
I'm thinking my symptoms have worsened due to low FT levels. I'm just curious about why the frees dropped with the addition of Cytomel. I also wonder if my Synthroid should be increased as well. I think it may be slightly weaker than the generic levo I was on before. About 6 weeks after the generic levothyroxine-to-Synthroid change is when I started feeling worse, but my tsh still dropped (I guess due to the Cytomel.)
Thank you for responding :)  All this seems so frustrating and complicated.

[Barb135]

You are right that your TSH is  meaningless, at this point.  Most of us on cytomel will have suppressed TSH, which is a pituitary hormone, anyway, and not indicative of your thyroid function, at this point.

Do you know if you have Hashimoto's Thyroiditis?  For those of us with Hashi's, it's not unusual to have to adjust medications as the antibodies destroy thyroid tissue, so it no longer produces hormones.  As the thyroid produces less hormones, you will need to increase your medications.

I'd also wonder if you've been tested for any vitamin deficiencies, such as B12, D, calcium, selenium, iron/ferritin, magnesium.  Deficiencies in any of these can cause symptoms; particularly, B12 deficiency.  Ask to get tested for these vitamins/minerals.  

[Josiecatgrl]

Thanks for the response. I guess I should've made it more clear that I've been taking Cytomel along w/ Synthroid since February & since then my FT3 level still dropped a little & my FT4 dropped a lot (labs as of 4-28-11). I felt pretty good for a few weeks after adding the Cytomel (better mood, more energy, less hair loss), but recently have begun feeling bad again. Im just wondering why this happened. Doesn't FT3 normally rise with Cytomel? I haven't started the new, higher dose yet, but will tomorrow. I also wonder if my Synthroid should be adjusted upward too since my FT4 level dropped so much.
I know I'm lucky to have found this endo (most won't even consider Cytomel.) He really didn't want to change my meds at all after these last lab results, despite the low frees. He relented enough to add a little more Cytomel after I called back and told him I really felt bad & wanted a med increase.

[FTB4]

Most Hypo sufferers feel better and less symptomatic when the T4 is about half way up the ref. range, The Free T3 is about 2/3rds up in its ref range and the TSH is supressed, so I would not be concerned with your TSH, as it is not a thyroid hormone, Your MD is following the right path in adjusting your meds by symptoms and free T3, most do not have this benefit as many MD's treat by TSH and or Free T4 alone, when the most important is Free T3, since that is the hormone your body needs to function. It also takes up to 6 weeks for Free T4 and sometimes four weeks for Free T3 to get into your system.
Regards FTB4