Thyroid test

Have had a blood test sprung on me by surgery. How long before my test should I stop my B complex?

Di

[SeasideSusie Remembering]

We should leave off for 7 days according to Medichecks. Results may be false if B Complex containing Biotin or a Biotin supplement is taken and Biotin is used in the testing procedure, which many labs use.

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Thanks. Had a put myself in for a test in May before I self-sourced some T3. Now they have decided they want to test everything!

Di

[SlowDragon Administrator]

Saying you are taking Biotin and would need to stop that for a week before getting tested is always a good way to avoid a surprise blood test

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 . This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

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

If/when also on T3, make sure to take last small split dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test

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Luckily away in van for another month😂