Blood Drug Testing

Are you meant to take your usual dose of thyroxine on the day of your thyroid blood test?

Do doctor's usually prefer you to miss a dose or take a dose later on that day?

Public Comments

1. I never did take T4 before a mornning blood draw. I would test first, then take the med in the car. I am now on Armour and on Armour's website it says to test first and then take the med. I'll put the link below to show you. It states "If you take thyroid supplement medication on the day of your blood test, you should wait until after the blood has been drawn so as to avoid any test interference. Once the blood has been drawn, you may take that day’s dose and return to your regular dosing schedule"