Alternating Synthroid Doses

[suzymartin0505]

I have been taking Synthroid for 17 years now but my dose has changed after having children. (My last child was born 4 years ago.) I was taking 125 mcg but my TSH levels fluctuated between 3.5 and 4.9. I would often times feel sluggish and depressed. The doctor increased my dose to 137 mcg and after about 2 weeks of taking that dose my chest started to feel tight and I have felt jittery. It's only been 3 weeks now but I'm definitely more nervous and my chest still feels different. I'm not sluggish or feeling down anymore. Do you think I might need to alternate between 125 mcg and 137 mcg or should I go back down to 125 mcg? I take the actual Synthroid, not the generic. I have not been feeling hot, my hands are not shaking and and my pulse isn't speeding up, I just feel it in my chest and I can feel a little more nervous than normal. I'm afraid it will only get worse as the weeks go on. Thank you for your help.

[gimel]

Ranges depend on the units of measure.  For example, many labs use for FT3, a range that is around 2.3 - 4.2 Pg/ml, or 3.5 - 7.7 P mol/L.  for FT4 I frequently see ranges like .60 - 1.50 ng/dl, or 10.2 - 19.2 P mol/L.  Ranges differ a bit from lab to lab, because they tend to use their own test results and use statistical limits (reference ranges) to include 95% of the total data base.  I would be a bit suspicious of motivation when a lab has much broader ranges than the lab used by the Endo, unless you are talking about TSH.   The old TSH range was .5 - 5.0.  Over 8 years ago the AACE recommended that it should be revised to .3 - 3.0.  Many labs and doctors still do not use the new range.

The ranges should really be used as guidelines within which to adjust the levels as necessary to relieve hypo symptoms, without being constrained by resultant TSH levels.  This is my definition of clinical treatment, which is the most effective approach.  TSH becomes irrelevant when taking thyroid meds, regardless of what many doctors would have you believe.  TSH is often suppressed when taking thyroid meds.





  

Whatever range is used,

[suzymartin0505]

Thank you!!

One more question... what are the FT4 and FT3 ranges? I've found that the ranges my HMO's lab relies on are much broader than an endocrinologist's ranges.

Thanks again!

[flyingfool]

ABSOLUTELY you need to focus more on the FREE T3 and FREE T4.  Not and I repeat NOT on the total T3 & Total T4.  The Totals are an outdated test.

It is nearly impossible to adjust your medication dosage based upon TSH.  Especially once you start taking thyroid meds which can suppress TSH rendering it almost useless.

Everyone is different but as a general rule people tend to feel symptom relief when their Free T4 (FT4) is about mid range AND their Free T4 (FT3) is in the UPPER 1/3 of the range.  Again everyone's tolerance is a bit different so some will or can go Hyper when only slightly above mid range on T4 for example.

The thing to be aware of is that the "normal ranges" are FAR too broad and simply being within the "normal" range is simply NOT good enough!  Many people are Hypo and remain in the lower part of the range.  DO NOT accept the Dr. saying "your normal" if you still feel like crud.  Insist on the both FREE's to be tested.

Please post your test results and the reference ranges and folks here will help give advice as to what they think.  From your anecdotal description it appears you are fairly sensitive and you may be trending towards Hyper and you definitely should talk to your Dr.  It is not all that surprising that this is happening if your Dr is trying to adjust your dosage based only on TSH.

Symptoms correlate the best with FT3. There is almost no correlation in clinical tests with TSH or even FT4.  Which makes perfect sense because it is ONLY the FT3 hormone that that body actually uses.

[suzymartin0505]

Thank you for your suggestions. I will definitely talk to my doctor about either alternating my dose or taking two half pills to make 131 per day.

He does test my T4 and T3 sometimes, but he does not test them every time he tests my TSH. The last T4 was within range but my T3 was at the very top of the range, somewhere between 37 and 39.

Should I focus more on the T3 and T4 results than the TSH? Or do they all go hand in hand and need to be within the proper range to determine the correct dose of synthroid? What are the best ranges for all 3 individually?

Thank you again for your help.

[goolarra]

You're right that if you've only been on the new dose for two weeks, it will continue to build in your blood.  It takes 4-5 weeks to reach it's full potential after a dose change.  

If I were you, I'd talk to my doctor about alternating.  You can also break both a 125 and a 137 in half and take both halves every day for a uniform 131 per day.  If that's still too high a dose, you can always do a 125/125/137 three-day rotation (be sure to write down what you take each day!!!).

Is your doctor testing free T3 and free T4 along with TSH?  FT3 and FT4 are the actual thyroid hormones and should be used, along with symptoms, to adjust meds.  It sounds like your doctor pays attention to your symptoms...that's really very positive and amazingly hard to find.

Good luck with the adjustment...it sounds like you're very close to your optimal dose.