I Have A Normal TSH , But Slightly Low Free

Posted on Sat, 1 Sep 2018

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Sat, 1 Sep 2018 Answered on

Tue, 27 Jun 2023 Last reviewed on

Question : I have a normal TSH, but slightly low free T4 at 0.7 (reference range being low end 0.9). Is this low enough to be considered hypothyroid (secondary)?

Answered by Dr. Olgeta Xhufka (1 hour later)

Brief Answer:
Do more examinations because secondary Hypothyroidism is suspected

Detailed Answer:
Hello dear, welcome to Ask a doctor service.
I read your query and here is my advice.

Free T4, is low referring to the range. I suspect it may be secondary Hypothyroidism which is caused by low levels of pituitary glad hormones.
To confirm that you should measure the levels of LH, FSh, total testosterone, cortisol, Prolactin, TSH and fT4. Even a MRI of pituitary glad.
If this hormones are low it may be a secondary Hypothyroidism.

Hope I have answered the question. Let me know if I can assist you further.

Above answer was peer-reviewed by : Dr. Nagamani Ng