Stopping Meds before lab tests
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When performing lab tests you sometimes need to stop your medication before the blood draw. This is a list of the common withdrawal periods. Unless specified otherwise you only have to stop taking the hormone being tested for.


Don't take any thyroid medication on the day of the blood draw but take your bed time dose as usual if you want the most accurate results. (Consider not taking any T3 after lunchtime the pervious day, especially if your Dr gets concerned by over range FT3). You can take your HC as normal on the day of the blood draw if you are on it. (updated 12/12)

Cortisol/Adrenal support

The "gold standard" for Adrenal hormones is the "4 times a day saliva test". These tests are not  accurate though if you have taken any cortisol (HC) or Isocort within the preceding 2 weeks. If you are on HC and trying to establish dosage then temperature is the best indicator, as low a dosage as you can take and still keep a stable temperature is the optimum.

Sex Hormones

If you are supplementing sex hormones using creams applied topically then saliva tests are not accurate. Blood tests remain accurate if you are supplementing but none should be taken on the day of the test.

Ferritin/Iron Panel

If you are testing for Iron you will get distorted results if you take any iron supplements within 5 days of the blood draw.