My free T3 level should be checked how often if I am on synthroid (thyroxine)?

Never. In hypothyroidism, the TSH is the best indicator of whether you are on an adequate dose of medication. Checking T3 (liothyronine) is generally only useful in patients whose thyroid is overactive.

Related Questions

My wife's free t3&t4 in normal range but her ths is low, it's 0.04. She've been taking thyroxine sodium 175mg for the past 6 months any recomandation?

TSH. She may be subclinical hyperthyroid. Does she have symptoms of hyperthyroidism?Anxiety, increased heart rate, insomnia? Make sure she gets her thyroid panel checked again. Depending on the results and her symptoms, her physician make readjust the strength down. It takes time to get individuals level. Read more...

My free t3/rt3 ratio is 13.6 and I feel worse on synthroid (thyroxine). Should my 4th endocrinologist consider this and any suggestions if they choose not to?

They all should. Totally ignore your t3/rt3 ratio as it is meaningless. The serum levels of these two hormones have absolutely no clinical significance -- it's the levels inside the cells that matter, and they are not able to be measured with blood testing. Don't get your medical information from friends, tv or internet scams. Read more...

Thyroid: free T3 low, all other tests normal, so do I need synthroid (thyroxine)?

Not sure if need any. The TSH is normal so it might be a variation of normal or euthyroid. It also might be a developing thyroid condition, but there would be symptoms, like fatigue. It would be wise to see your doctor to follow up. Read more...

Free T3 was 2.051, T3T 76. T4 & TSH in range. Added 5mcg Cytomel to 75mcg Synthroid (thyroxine). Still temp. Sensitive, but *really* anxious. Stop Cytomel?

Stop cytomel (liothyronine) how long after taking cytomel (liothyronine) , did you get the levels taken?----all of your labs are essentially normal. but it take about 30 days before thyroid meds will affect the lab values... but sice cytomel (liothyronine) is synthetic T3----and the symptom of too muc T3 is anxiety---- eith stop the cytomel (liothyronine) or use 1/2 the dosage--- and see if it helps----follow up with your private doctor. Read more...
See doctor/Endocrine. It's possible that you do not convert T4 to T3 very well. Consider lowering your Synthroid (thyroxine) dose with your doctor's collaboration. T3 is 4 times more powerful with a short half life (some state 4 - 8 hours up to 1 day) compared to the T4 half life of 5 - 7 days. More commonly a smaller dosage of T3 added to existing T4 is given, but perhaps you need a lower dose of Synthroid (thyroxine). Read more...

Tsh=2.11/t3 uptake=30.3/free t3=3.3/thyroxine=9.2/triiodothyronine=102.4/ everything is normal. Why do I still feel extremely tired and irritable?

Thyroid level normal. Many people feel tired and irritable. Most of these people have no problem with their thyroid. You need to look for other causes for your symptoms, as they are not due to a thyroid problem. Read more...
Reverse T3 (liothyronine) RT3 was not checked. A TSH of 2 is suspicious. More info on http://drfairchild.blogspot.com/2012/12/proper-thyroid-testing.html. Read more...

My thyroid numbers: TSH 3.38 mcIU/mL Free T4, 1.06 ng/dL Free T3 2.8 pg/mL Reverse T3 15 ng/dL My son's on synthroid (thyroxine). But are MY numbers optimal?

Interesting question. Optimal is a interesting question. First it is important to understand where "normal" is derived. "Normal" ranges for each lab is a statistical number that tell where a population of "normal" people results run. So your numbers run within the "normal" (reference) range for most laboratories. Are your results "optimal" is a question that is thus difficult to answer! Read more...