Thyroid

Is a TSH level of 0.100 very low?

[CarolG52]

What is the reference range your lab uses?  Either way I would say it seems low?  Did you have any other tests done beside that one, such as FT4 and FT3?  All these together give a clearer picture.

[goolarra]

Reference range for TSH is 0.3 to 3.0.  This is defined by the AACE (endocrinologists).  Even though different labs have different ranges on their TSH reports, "we", here on the forum, generally disregard them and use 0.3-3.0.  So, yes, 0.1 is quite low.

nazhoni:  Are you on thryroid meds?  Have you been diagnosed with a thyroid condition?  I agree with CarolG52, you need to get FT3 and FT4.  With FT3 and FT4, you do have to supply the reference range that your own lab uses, since different labs use different ranges, different units, etc., and we're dealing with different countries..  

[nazhoni]

I had thyroid cancer and had a thyroidectomy a year ago.  After my first scan my doc increased my synthroid dosage to 125mcg.  he said a higher dosage can help prevent the cancer from recurring. About 3 mos. ago I began having heart palpatations, irregular beats, and fatigue.  2 weeks ago my doc lowered my dosage to 100mcg, but I am still having symptoms of hyperthyroidism.  Does it take a while for the symptoms to dissipate?

[goolarra]

It does take a while for the symptoms to dissipate, especially if you've been overmedicated for perhaps three months (when your palps, etc. started).  TSH of 0.01 is quite low, but after a TT, doctors usually want to keep it pretty low.  However, if you are having hyper symptoms, you're body is telling you something.  Does your doctor order FT3 and FT4?  These are sooo much more important than TSH.  After my last levo increase, I started having hyper symptoms.  My doctor advised me to stop all meds for three days, and then resume at the old dose.  Perhaps you could ask you doctor if this might help you?