Preferred amount: 1.0 mL Serum or Plasma
Minimum amount: 0.5 mL Serum or Plasma
Centrifuge required?: Yes
Special Instructions: Because of nocturnal rise in intact PTH levels, samples should be collected in the morning, after 7 a.m., preferably after an overnight fast.
To help diagnose the reason for a low or high calcium level and to help distinguish between parathyroid-related and non-parathyroid-related causes. It may also be ordered to monitor the effectiveness of treatment when a patient has a parathyroid-related condition.