Parathyroid hormone (PTH)
Parathyroid hormone (PTH) is a hormone of the parathyroid glands (four tiny glands next to the thyroid) that regulates calcium: when calcium drops, PTH rises and raises it (from the bones, kidneys, via vitamin D), and vice versa.
| Rating | Range | What it means |
|---|---|---|
| Talk to a doctor | below 1.6 pmol/L | Low PTH — context (calcium). |
| Good | 1.6 – 6.9 pmol/L | Within the reference range. |
| Talk to a doctor | 6.9 pmol/L and above | Elevated PTH — parathyroid glands/vitamin D; consult. |
Why it matters
Evaluate together with calcium and vitamin D.
If it’s low
Low PTH often accompanies high calcium from another cause (the body correctly suppresses PTH) or underactive parathyroid glands.
If it’s high
High PTH can mean overactive parathyroid glands (raising calcium), or the body is defending against low calcium/vitamin D (secondary). The pattern with calcium tells which of these it is.
What to do
ALWAYS read PTH together with calcium and vitamin D — only the pattern reveals the cause. Correction often goes through vitamin D; a doctor manages parathyroid diseases.
Read together with
Calcium · Vitamin D · Phosphate · eGFR
Articles about this marker
- Vitamin D: what your value means and how to raise your levelMarker explained
This content is for information only and is not a substitute for medical advice. Talk to your doctor about your results.
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