Preparing for Your Thyroid Function Blood Test
Drink plenty of water, around two to three full glasses, 1 to 2 hours before your test to stay well hydrated for better blood flow. While fasting isn’t required, try to avoid fatty foods for at least eight hours beforehand. Avoid coffee, tea, or energy drinks, and stick to water only.
- Timing: Collect your sample between 6:00 am and 10:00 am. Only take this test once any symptoms of short-term illness have resolved.
- Supplements: Ensure at least 24 hours have passed since taking any vitamin or mineral supplements.
- Biotin: Avoid biotin supplements for 72 hours before the test. If biotin has been prescribed, consult your doctor before stopping it.
Medications:
If you take thyroxine, you may take it as usual, either before or after your test.
If you take desiccated thyroid extract (DTE) or liothyronine, collect your sample before taking your medication.
Please write on your lab request slip, if you are taking amiodarone or lithium, as these can affect your results.
Please note that following the instructions step by step is crucial, as not following them may lead to sample rejection.