Parathyroid Hormone (PTH)

TIMING: Draw in the morning — PTH has diurnal variation (higher overnight/early AM, lower midday). For trending, always draw at the same time of day. PTH is unstable in blood samples — the hypoparathyroidism community emphasizes that the sample must be processed quickly and kept cold (ice). If your lab doesn't spin and freeze the sample promptly, PTH can degrade and read falsely low. Always interpret PTH alongside calcium (ideally ionized calcium), vitamin D, phosphorus, and magnesium — never in isolation. For hypoparathyroidism patients on treatment, PTH will typically be undetectable or very low; calcium and phosphorus are the monitoring targets. These notes reflect common practices in endocrine patient communities.

Reflects common practices in thyroid, BHRT, and functional medicine communities. This may differ from standard clinical guidelines. Not medical advice — always discuss with your provider.