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Does Levothyroxine Cause Hair Loss?
Question: Hi I recently had some blood work done for a check on my thyroid. The tests I had were TSH of 4.8, thyroid Microsomal antibodies of 130, Free T4 of 1.27 and thyroglobulin of 588. When I went for the blood draw I asked if I needed to fast for these tests and was told no. I subsequently found out through reading that I should have fasted for these tests. My doctor has prescribe 50 mcg of levothyroxine. Should I have these tests redone because I did not know to fast and will taking this drug cause hair loss ?
Brief Answer:
Thyroid
Detailed Answer:
There is no need to fast for thyroid related blood tests.
It is extremely unlikely that your test results would be significantly different if you had fasted.
That being said, there is some variation in the laboratory values of TSH and Free T4 depending on time of day, but it is not enough to warrant a change in the approach to diagnosis and treatment.
In fact, there are limitations of the TSH blood test for instance. So if you were to re-check the same TSH in the exact same blood sample that you submitted to your lab, it is possible the reading would be upto 20% on either side of the actual value.
Moreover, if you submitted the same blood sample to another laboratory with a different method of testing, the TSH would likely differ by a similar margin.
And if you gave separate blood sample at more or less the same time , in the same lab and another, the results would likely vary even then.
So endocrinologists tend to look at TSH in the context of the Free T4 and thyroid auto antibodies. Yours are positive. With a mildly elevated TSH and normal Free T4, the medical term for this condition is 'Subclinical' or Early Primary Acquired Hypothyroidism, possibly permanent due to Chronic Autoimmune Lymphocytic (Hashimoto's) Thyroiditis. What this jargon simply means is that it quite likely you have a mildly underactive thyroid gland which could benefit from treatment with levo thyroxine.
This medication does not cause hair loss unless taken in excessive amounts. This is unlikely to happen if you are under the regular follow up of a qualified endocrinologist
Thyroid
Detailed Answer:
There is no need to fast for thyroid related blood tests.
It is extremely unlikely that your test results would be significantly different if you had fasted.
That being said, there is some variation in the laboratory values of TSH and Free T4 depending on time of day, but it is not enough to warrant a change in the approach to diagnosis and treatment.
In fact, there are limitations of the TSH blood test for instance. So if you were to re-check the same TSH in the exact same blood sample that you submitted to your lab, it is possible the reading would be upto 20% on either side of the actual value.
Moreover, if you submitted the same blood sample to another laboratory with a different method of testing, the TSH would likely differ by a similar margin.
And if you gave separate blood sample at more or less the same time , in the same lab and another, the results would likely vary even then.
So endocrinologists tend to look at TSH in the context of the Free T4 and thyroid auto antibodies. Yours are positive. With a mildly elevated TSH and normal Free T4, the medical term for this condition is 'Subclinical' or Early Primary Acquired Hypothyroidism, possibly permanent due to Chronic Autoimmune Lymphocytic (Hashimoto's) Thyroiditis. What this jargon simply means is that it quite likely you have a mildly underactive thyroid gland which could benefit from treatment with levo thyroxine.
This medication does not cause hair loss unless taken in excessive amounts. This is unlikely to happen if you are under the regular follow up of a qualified endocrinologist
Note: For further follow up on related General & Family Physician Click here.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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