Hypothyroidism and prolactin

[Jessica1987]

Does hypothyroidism cause moderately elevated prolactin levels. Does this come down when thyroid levels are optimal?

[helvella Administrator Thyroid UK]

Jessica1987,

TSH and Prolactin are both produced in the pituitary gland and under the control of the hypothalamus.

There is a tendency for the pituitary to enlarge in hypothyroidism.

The upshot being that alongside an increased TSH - the obvious consequence of hypothyroidism - so too do we (often) see raised prolactin.

I wouldn't word it as hypothyroidism causing moderately elevated prolactin levels. But yes, in hypothyroidism prolactin often rises. Also, often, the prolactin level drops when hypothyroidism is adequately treated.

[Jessica1987 in reply to helvella]

Thanks so much 😊 I will do another female hormone test in a few months a see whether it’s falling now My thyroid is in optimal

[Sandra600 in reply to Jessica1987]

My prolactin level used to be raised and it has normalised since my hypothyroidism has been treated.

[Hashihouseman]

Absolutely it does. It plays havoc with my testosterone! So much so that I take sage oil to reduce it and test my prolactin levels whenever I test my thyroid levels and proved beyond doubt that as tsh goes up so does prolactin and when it goes down prolactin also goes down. It’s so profound that I use prolactin levels to help identify when my TSH and thyroid hormone levels are optimal. It’s not an enlargement of the pituitary that does this (I did a brain scan to check that) it’s simply stimulation of the pituitary and the physiological links between the sex and thyroid hormones. There could well be some (female) purpose in the body linking tsh and prolactin but for me it’s a nuisance and I can’t get it low enough without suppressing tsh, which isn’t a good thing either. That said my prolactin is always clearly in excess of the upper range for males if my TSH goes above 2 and significantly within range (albeit still too high) if TSH is below 1 but since this fluctuates between 1 - 3 normally maybe there’s nothing I can do about it. I tried L-dopa suppression of prolactin (which works) but this also seems to suppress TSH (probably due to the pituitary linkage) and that confuses assessment of thyroid balance. All very complicated!

[Hidden in reply to Hashihouseman]

Mine Prolactin is at 600 last test again! i do have a Tumour but small

[Serendipitious]

Did you get any symptoms such as leaky breasts? Or was it just raised in your blood test?

[Carriebaby in reply to Serendipitious]

I had leaky breasts way before I was diagnosed with an under active thyroid and my prolactin levels were too high so it is defiantly linked

[Serendipitious in reply to Carriebaby]

I’ve just received my result today. What was your result?

Plasma prolactin level 156 miu/L [59.0 - 619.0]

Prolactin female reference interval:

Pre-menopausal 59 - 619 mIU/L

Post-menopausal 38 - 430 mIU/L

[SlowDragon Administrator]

2 months ago your post shows under medicated on only 75mcg levothyroxine

healthunlocked.com/thyroidu...

Have you had increase in levothyroxine to 100mcg

TSH should be under 2 on levothyroxine and ALWAYS under 2 before TTC

Most people when adequately treated on levothyroxine will have TSH around or under one. Most important results are Ft3 followed by Ft4

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12

Low vitamin levels are extremely common, especially if you have autoimmune thyroid disease (Hashimoto's) diagnosed by raised Thyroid antibodies

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

Private tests are available as NHS currently rarely tests Ft3 or thyroid antibodies or all relevant vitamins

List of private testing options

thyroiduk.org/getting-a-dia...

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Thriva Thyroid plus antibodies and vitamins By DIY fingerpick test

thriva.co/tests/thyroid-test

Thriva also offer just vitamin testing

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins by DIY fingerprick test

bluehorizonbloodtests.co.uk...

If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3

£29 (via NHS private service ) and 10% off down to £26.10 if go on thyroid uk for code

thyroiduk.org/getting-a-dia...

monitormyhealth.org.uk/thyr...