if my thyroxine is reduced how long will it be before it shows in a blood test. i.e what is the shelf life of thyroxine in the body

[GLENNIE]

[nobodysdriving]

it will take a good 4 to 6 weeks to really go

[marram]

I second that.

[KennyGee]

Thyroxine has a half life of around 8 days. That means that after 8 days half of its potency has gone. After another 8 days half of what remains is gone and so on, so it takes a while to be totally clear but you can see that after 16 days three quarters of it has gone.