Do antihistimines affect thyroid blood tests? Test on Wednesday with rt3. Help!

[BexyLS]

Does anyone know if antihistimines and glucocorticoid spray affect thyroid blood tests results. Should I stop taking them before the test and when? Thanks

[gabkad]

Bexy, the nose spray is only 25 mcg per dose and supposedly only topical. I can't see how that would affect the thyroid testing. Don't know about the antihistamines.

[Heloise]

Do you think it might be good to find out the effect they DO have on your levels? If so, you should take them.

Remember if you do not want to appear you have higher than normal Thyroid levels, you should wait until after the test to take your thyroid hormone.

[Helenback in reply to Heloise]

If you leave taking your thyroid meds till after blood test what do you tell the person taking your blood when they ask when did you take you last dose?

[Heloise in reply to Helenback]

Oh, tell them the truth. Even they may know that taking your hormone before the test may give you a false reading. It is recommended by STTM and has been by almost everyone here.

[Helenback in reply to Heloise]

OK will do thanks Heloise

[Jackie]

Hi They never effect my tests.

Jackie

[BexyLS in reply to Jackie]

Hi Jackie, thanks, found this The effects of drugs on tests of thyroid function. ncbi.nlm.nih.gov/pubmed/188...

Signed up but have no idea how to read the full report. Can you help? thanks

[Jackie in reply to BexyLS]

Hi They do not mention antihistamine, only the well known ones. However, if still worried take it after the test.

Jackie

[Jennyfluff]

I am on Telfast, 180mg prescribed antihistamine plus OTC antihistamines, and sprays for my numerous allergies and puffers, I have not noticed it affecting my test results either because it affects the Ig levels which I believe has nothing to do with thyroid testing. Unless it is hyperthyroidism then I would imagine Pseudoephedrine in OTC preps will affect that result in some way because it is a stimulant, have you thought of looking up some research papers on antihistamines etc on thyroid treatments? Also if you look at the contra indications or possible side effects it might list it there. Just a thought, hope it is helpful in some way.

Good luck.

Jen

[BexyLS in reply to Jennyfluff]

This is the problem I cant find anything. Im googling "what medications interact with thyroid blood tests" maybe im using the wrong words?

[Jennyfluff]

Values may be lowered with use of aspirin, corticosteroids and heparin therapy.

Values may be raised with use of lithium, potassium, iodide and TSH injections.

The T4 blood test can also be used to monitor the effectiveness of medications used to treat thyroid disease. Estrogen, anticonvulsants, aspirin use and anticoagulants may affect T4 levels. They are increased with pregnancy.

I found this my.clevelandclinic.org/hear...

hope it is helpful. no mention of antihistamines at all anywhere.

best of luck

jen

[BexyLS in reply to Jennyfluff]

Thank you thats great Jen much appreciated

[Jennyfluff in reply to BexyLS]

Happy to return the help as I have had LOADS on here, so no problem, just glad we managed to sort it out. Take good care love.

Jen