What's best time for blood test?

[Sugaru]

What's best time for blood test? I posted recently my blood test which showed b12 of 149. Doctor is going to repeat test and refer to endocrinologist if it is still low. My blood test is booked for 12.20 is there an optimum time for bloods?

[Clutter]

Sugaru,

Thyroid blood tests should be done early in the morning when TSH is highest and you should fast (water only) as TSH drops after eating and drinking.

I don't think it matters what time blood is drawn for B12 and other tests.

[shaws Administrator]

If she is also taking your thyroid hormone, you should also allow 24 hours approx between your last dose of levo and the test and take it afterwards.

[shaws Administrator]

This is a diurnal map of the TSH just for info:

drive.google.com/file/d/0B9...

[Sugaru in reply to shaws]

Thanks that is helpful, I think I'll try to change it to a morning one.