Test Preparation Instructions

Blood Tests

Lab tests that require fasting (nothing but water after the evening meal on the day before your test):

  • cholesterol
  • HDL cholesterol
  • triglycerides
  • lipid panel
  • fasting glucose
  • growth hormone
  • vitamin B12
  • folate
  • glucose tolerance test

Lab tests to be drawn before 9:00 AM:

  • testosterone
  • AM cortisol
  • pituitary function tests
  • thyroid function tests: TSH, Free T4, Free T3, Total T4

Thyroid Function Tests:

Ideally, we recommend that you have your thyroid function tests done in the morning so we can be consistent in the way we measure your thyroid function. We also recommend that you take your thyroid medication after you have your blood drawn on the morning of your blood test. This is especially true if you are taking a T3-containing medication (liothyronine, Cytomel, Armour Thyroid, NatureThroid, natural thyroid or desiccated thyroid hormone, sustained-release T3, etc.).


On waking in the morning, begin the test by urinating into the toilet and flushing. Record this as the start time.

  • Collect every drop of urine you produce during the day and night in the collection bottle. Store the bottle in the refrigerator during the test.
  • When you wake up the next day urinate and collect the urine in the collection bottle. Record the time as the stop time.
  • Store the urine in the provided collection bottle in the refrigerator until it
    can be dropped off at the laboratory.